watts ohms and a headache
Badbetty
I have realised I know little about sound reinforcement and PA systems.
I have a power amp (2 x 1000w into 4ohms) or (2 x 600w into 8ohms).
To it I want to connect some speakers but I have run into a headache.
I have been told that with a bass bin (/sub) with passive crossover and
satelite tops, that in truth only the load of the sub is seen by the
amp.
e.g. 1 x sub @ 600w 4 ohms + connected satelite 400w @ 8 ohms - the amp
really only sees the sub load and in the case of the amp above, it
would fry it at full power.
so, does this mean if i had a 600w sub at 8ohm with an 8ohm 200w top
(for instance) that this would be ok on the above amp because the sub
is 600w at 8ohms.
or could i have a 400w sub @ 8ohm and a 300w top at 8ohm and this too
would be ok? or would it be the same as i was first told - the 400w sub
is all that is seen and it too would be fried.
anyway all this stuff is news to me (i thought i had a fair grasp but
not anymore) and i want to ask you all about watts, ohms and subs +
satelites; and what can i get (using passive crossover or just a full
range perhaps) to hang off the above amp that will work best for a
small rock band with everything mic'd up?
any comments on any/all of the above are really appreciated.
Thank you.
Badbetty
honestly, in a full range cab with 12" cone - how different (good or
bad) in truth is the sound compared to using 15" or 18" etc.
Is it really possible to get away with a 12" cone and not suffer
massive bass depravation etc?
Thank you
GregS
>a small addition for some extra comments please:
>
>honestly, in a full range cab with 12" cone - how different (good or
>bad) in truth is the sound compared to using 15" or 18" etc.
>
>Is it really possible to get away with a 12" cone and not suffer
>massive bass depravation etc?
If your not using a sub, no.
I was getting a headache reading the biginning part.
greg
Greg Cameron
Is the power rating on the sub the rms rating or the program rating? If
600 watts is the rms rating, then a 1000 watt amp should be fine, so
long as you're not clipping it. If the program rating of the sub is 600
watts, then you'll likely over power it.
Greg
liquidator
"Greg Cameron" <cameron...@linkline.com> wrote in message
news:1154622711.7...@i42g2000cwa.googlegroups.com...
We need to post a Newbie FAQ- it would be best if they tell us what they
actually have.
All 600 watt subs are not created equal.
--
Posted via a free Usenet account from http://www.teranews.com
Badbetty
ok i have the amp as described carlsbro powerline 2000 (2x 1000w @ 4
ohm or 2 x 600w @ 8 ohm).
what combi of subs and tops can i put on it:
eg. what about Carlsbro Gamma 600/15p (600w@4ohm) with a Gamma 300/12p
(300w@8ohm)? [pls if you think they are crap sound that doesnt matter]
as i said i am told that the amp only sees the sub load and does not
care about the top connected to it. ?
alternatively:
carlsbro 112 pro (600w at 8ohm [fullrange?] ) with Beta Pro sub 600w
@ 8 ohm?
OR
what can you recommend at 4 ohm or 8 ohm to connect to the amp - that
is not bigger than the above to carry etc.
look forward to your constructive remarks.
Thank you again.
mackerr
Badbetty wrote:
>
> as i said i am told that the amp only sees the sub load and does not
> care about the top connected to it. ?
>
>
The crossover in the sub is like the crossover in any passive full
range system. Speaker impedance is a complex parameter, and will vary
with frequency even on a single driver. In your case the impedance of
the system will be something like the specified sub impedance at sub
frequencies, and something like the specified full range impedance at
those frequencies. It is unlikely to be exactly the specified impedance
except at a specific frequency.
Mac
Greg Cameron
I had a look at the Carlsbro site. Their specs leave something to
desired, not to mention the web site. Anyway, that model of sub is
rated 1200 watts program, so that amp should be an ok match. However, I
could find no information about the sub that would indicate it has a
passive crossover network to high pass signal to the top boxes. You
need either some type of passive cross-over network to use the same amp
channel feeding the sub to also feed the tops, or you need to use an
additional amplifier for the tops with an outboard active crossover or
processor and split the highs and lows before the signal reaches the
amp inputs from the source. Keep in mind whatever amp you choose to
power your tops should have power output close to the program power
rating of that speaker at the given impedance rating (ohms).
Greg
Ron(UK)
>
> eg. what about Carlsbro Gamma 600/15p (600w@4ohm) with a Gamma 300/12p
> (300w@8ohm)? [pls if you think they are crap sound that doesnt matter]
>
Actually, the Gamma 300'12`s are pretty good especially considering how
little they cost,
they have B&C drivers in them, are pretty rugged, and sound a lot better
than most plastic boxes in their league
IMO of course
Ron(UK)
--
Lune Valley Audio
Public Address Systems
Hire Sales Maintenance
www.lunevalleyaudio.com
Badbetty
Are you sure Greg?
the Powerline 2000 delivers 1000watts RMS into 4 ohms and 600watts RMS
into 8ohms. that's from each channel. Does that alter anything you have
said?
The Gamma sub is rated only 600watts RMS at 4ohms.
The crossover is in there (I have been told) but you are right, the
info and the site of Carlsbro is poor!
liquidator
"Badbetty" <b...@genie.co.uk> wrote in message
news:1154636100.8...@75g2000cwc.googlegroups.com...
Generally I run twice the rated power into my speakers. This gives more
headroom.
1000 watts should NOT blow a 600 watt speaker.
However if you clip the amp, you can blow it with a 200 watt amp.
Your friend who says the amp will only see the sub load is vastly over
simplifying things. Many people get stuff from a store salesman, and most of
them are clueless.
The only way to really know the impedance load is to measure it. Carlsbro
probably hasn't done this
I'm not making snide remarks about cheap equipment. I am aware of the need
for it. Just be aware why it is cheap. Often the manufacturer just skips a
lot of testing. Someone who does their homework can get cheap stuff to sound
better.
If the subs don't have a crossover, I would suggest running the system mono.
Get an electronic xover and run subs on one channel and tops on another.
George Gleason
> headroom.
>
> 1000 watts should NOT blow a 600 watt speaker.
>
> However if you clip the amp, you can blow it with a 200 watt amp.
only if said 200 watt amp is putting out more than 600 watts when clipped
or if the speaker is not REALLY a 600 watt speaker
Clipping makes no diffrence as long as thermal ,mechanical and excursion
limits are not exceeded
George
GregS
If its just a sub, clipping is not going to do a lot. The harmonics fall up into the
region where the sub is significantly higher than the rated Z. If there
are pasive mids and highs, thats another story.
greg
Greg Cameron
The basic guideline of powering speakers is to give them approximately
2x the rms rating of the speaker. Arguably, the term "rms power" for
amps can be considered a misnomer. Continuous or average power is what
is really meant, but rms has become a common synonym for continuous or
average power. That aside, the program rating of a speaker is generally
indicates the what size amp should power that speaker. There are
exceptions to this guideline depending on application, but it works in
most cases.
Greg
liquidator
"George Gleason" <tbmo...@peoplepc.com> wrote in message
news:YetAg.2791$xp2....@newsread1.news.pas.earthlink.net...
George you are WRONG. The speakers are rated 600 watts sine wave (or less),
Not 600 watts square wave.
It is true clipping makes no difference if thermal limits are not exceeded.
However thermal limits are reached at lower power levels with clipped
signals.
A 30 watt gutar amp can burn the coil of a speaker rated at 100 watts clean
power.
Check out Danger Low Power at JBL's tech page.
liquidator
"GregS" <szek...@pitt.edu> wrote in message
news:eatnb0$43c$2...@usenet01.srv.cis.pitt.edu...
Not true Greg. There is much more energy under a sqaure wave. Rather than
argue, talk to someone who knows, like one of Eminence speaker designers.
Jerry is a good guy to talk to there.
Greg Cameron
In this instance power or watts are an absolute. Whether the waveform
is sine or square, the defined amount power is the same. i.e. 100 watts
is 100 watts if it's square wave or sine wave AC. What happens when an
amp is clipped is that power increases from more current being
delivered to the load since the harmonics are numerous and completely
fill in where there would normally be dips between the signal crests,
peak to peak voltage remains the same for the harmonics and root
frequencies. When clipping to the point of a square wave, you can only
exceed the unclipped signal's maximum power by 100% and no more. That
said, you can power a driver that is rated at 200 watts rms with a 50
watt amp at full clip without ill effects since the speaker is only
dissipating 100 watts in that case. Drive that speaker with a fully
clipped 100 watt amp, and you might be pushing it depending on how well
the speaker was tested and rated. Drive it with fully clipped 120 watt
amp, and you're going to have issues.
Multi-way systems with a passive crossover can present a different
challenge in regards to power amp clipping, as the higher frequency
harmonics from the clipped signal can pass through the crossover and
into the MF/HF drivers. If the power of those odd order harmonics
exceeds the rms rating of those drivers, you can toast them. But that
all depends on the size of the amp in relation to the driver and the
harmonics passing though the crossover network.
To conclude, it's not the waveform that's the issue, it's the power. If
waveform were the issue, rock guitar speakers would be blowing all day
long due to the fact they're being driven with fully clipped signals
constantly.
Greg
liquidator
> To conclude, it's not the waveform that's the issue, it's the power. If
> waveform were the issue, rock guitar speakers would be blowing all day
> long due to the fact they're being driven with fully clipped signals
> constantly.
>
>
last 20 years.
Discussions with numerous speaker engineers say waveforms are the issue. It
is possible to burn up a 600 watt coil with an amp that doesn't even draw
600 watts from the wall.
The 600 watt rating is NOT with a continuous duty cycle. Jerry McNutt of
Eminence, for one, has stated flatly that the power rating derates with duty
cycle. The speaker runs out of time to dissipate heat.
That is why, with a lower duty cycle, a speaker can handle twice it's RMS
rating
If the speaker was rated at absolute power you would be 100% correct. But
they are not rated that way. The power rating assumes a certain on/off time
which gives the coils time to dissipate heat. Take that away and it will
burn at lower power.
In that case the speaker would no longer be rated 600 watts.
Some of this is going to depend, obviously, on how honestly the
manufacturer rates their speakers.
Ther would be no hard and fast spec- each case would have to be determined
by experiment. But you CAN destroy a speaker thermally without the amp
putting out it's rated power.
If you can't engineers from 3 different companies don't know what they are
talking about.
liquidator
"liquidator" <liqui...@collide.org> wrote in message
news:44d27211$0$5395$8826...@free.teranews.com...
I may not be expressing myself well. What I am trying to say, is the speaker
is not really rated 600 watts in absolute terms. It is rated to be used with
a 600 watt amp with a certain type of input, often pink noise these days.
Change the input signal, and the rating will go up or down depending.
A 600 watt rating does not mean the coil can dissipate 600 watts
CONTINUOUSLY, the way a resistor would be rated.
Far from it. It may not be able to dissipate 300 watts continuously.
Resistors are rated with an absolute rating. Speakers are rated with a
SUBJECTIVE rating.
Hope this makes a little more sense...
Greg Cameron
You bring up an interesting point about the ratings. The testing method
is not included most of the time for the rms specs, so that would make
for a valid argument. Since I don't run these test on my own, it would
be impossible to say unequivocally what it's going to take to blow a
speaker then. It would be nice to have some real standards here. So I
guess along with the fact that speaker real world frequency specs at
actual operating levels along with actual measured SPL are not in most
specs, you also can't count on rms specs to mean the same thing from
driver to driver/box to box. A wise sound man once said to me that the
printed specs are an ok starting point, but often to apply in the real
world. I've always taken that to heart, but never suspected the rms
ratings on drivers would be "fudged" too.
Thanks,
Greg
Greg
Arny Krueger
> I may not be expressing myself well.
Your ignorance of standard electronics terminology is no doubt the cause.
> What I am trying to say, is the speaker
> is not really rated 600 watts in absolute terms.
To get standard terminology, replace "absolute" with DC or average , as
appropriate.
> It is rated to be used with
> a 600 watt amp with a certain type of input, often pink noise these days.
No mystery to those of us understand the difference between audio signals,
steady tones, or DC.
> Change the input signal, and the rating will go up or down depending.
Agreed.
A 600 wwatt rating does not mean the coil can dissipate 600 watts
> CONTINUOUSLY, the way a resistor would be rated.
Resistors are rated for dissipating DC power or average power.
> Far from it. It may not be able to dissipate 300 watts continuously.
No mystery to those of us who understand the difference between audio
signals, steady tones, or DC.
> Resistors are rated with an absolute rating.
No, they are rated for average power, or DC power.
> Speakers are rated with a SUBJECTIVE rating.
There's nothing subjective about it - you just follow the established
standards and conventions.
> Hope this makes a little more sense...
It makes for someone who in ignorance is making it up as they go along,
instead of referrring to standard terms.
liquidator
I try to be charitable to the manufacturers about ratings. It's not so much
that thay are fudging. It's just that there is not a real standard.
AES is probably the closest thing. But it is not an absolute rating. It is
a certain size amp with a certain type of input.
And to be frank, if a manufacturer did rate the speaker by the amount of
power it could dissipate continously, he'd be at a marketing disadvantage
since the others would be rating their speakers higher.
I like when a manufacturer specs something like "rated power for 8 hours
with pink noise". At least then you can get some idea of how the rating was
determined.
I'm glad I could finally say what I meant about the power ratings. Us
engineer guys sometimes have problems speaking regular human. I've struggled
to overcome that impairment most of my life. :-)
George Gleason
Then IMO rthe speaker is not correctly rated
the wattage rateing of a speaker should be its heat sheading ability with
any wave form
even straigh DC
I know the world does not agree with me
but it is not my fault 30 watt speakers are said to be able to handle 200
watts
gEORGE
>
George Gleason
>
> "Greg Cameron" <cameron...@linkline.com> wrote in message
> news:1154643537....@m79g2000cwm.googlegroups.com...
>> To conclude, it's not the waveform that's the issue, it's the power. If
>> waveform were the issue, rock guitar speakers would be blowing all day
>> long due to the fact they're being driven with fully clipped signals
>> constantly.
>>
>>
> In the old days they did. Thermal capacity has risen tremendously in the
> last 20 years.
>
> Discussions with numerous speaker engineers say waveforms are the issue.
> It
> is possible to burn up a 600 watt coil with an amp that doesn't even draw
> 600 watts from the wall.
>
> The 600 watt rating is NOT with a continuous duty cycle. Jerry McNutt of
> Eminence, for one, has stated flatly that the power rating derates with
> duty
> cycle. The speaker runs out of time to dissipate heat.
>
then the speaker is not correctly rated
> That is why, with a lower duty cycle, a speaker can handle twice it's RMS
> rating
>
> If the speaker was rated at absolute power you would be 100% correct. But
> they are not rated that way. The power rating assumes a certain on/off
> time
> which gives the coils time to dissipate heat. Take that away and it will
> burn at lower power.
then why not call it a 10,000 watt speaker as it will handle that power for
some infitisimal amount of time
the only rateing a speaker should have is a absolute power (heat
sheading)ability anything else is just playing with numbers
George Gleason
engineering dept
It is a full of shit rateing designed to sell more speakers
not a realistic , this is what the speaker is capable of rateing
Imagine buying a car that can put out 400 horsepower but neglecting to tell
you you need a supercharger to achieve that output level and then it can
only do it for a few seconds before you pretzel the crankshaft
tjhis is the equilvent of todays speaker ratings
George
liquidator
The problem is there is no word standard for speaker ratings. But even so,
what the speaker can sink contiuously may have nothing to do with what it
can stand with musical material.
A musical waveform has on and off cycles,or rising and falling power. During
on or high power, it generates heat. During off or low power it can get rid
of that heat. Actually, its getting rid of heat continously. It just isn't
being replaced, or not as fast.
Change the duty cycle to constant. The speaker then has a continuous input
of heat. It becomes obvious the speaker will get hotter with a longer duty
cycle. There is no "down" time, or period of less input.
At some point, the speaker can not get rid of the heat faster than it is
generated. This will happen at some point, whether you have a sine wave,
pink noise, or severely clipped input. It will happen at different power
levels with different input.
But where do you draw the line? Should a speaker be rated with 20%
clipping? Or 80 %?
Even if a speaker is rated at 80% clipping it still could be damaged by a
power amp less than it's rating. It can not sink the full power of the amp.
In reality it probably can for a while. And many amps would thermal if
driven that hard.
But one speaker might be able to sink 200 watts with a continous duty
cycle, and 600 with pink noise. Another might sink the same 200 but be able
to sink 1000 with pink noise. What is the correct rating? The pink noise
rating is probably more in line with running them unclipped.
Speaker ratings will probably never be more than a guideline for use. I
only wanted to make the point that speaker ratings change with different
input.
Unlike a resistor. Theoretically all 600 watt resistors can handle 600
watts. But that is another can of worms.
George Gleason
watts of heating under ANY condition and ANY duty cycle
that wayI know if I put a 200 watt amp to a 300 watt speaker it will not
blow,ever regardless if I send it out with a pro guy or arni
george
liquidator
The world does not agree with you apparently.
NOBODY has ever produced a speaker like that. Not JBL. not EV. Not the
Europeans. NOBODY.
And as I explained in another part of this thread, if they rated speakers
the way you want it would be meaningless in most applications. How much
continuous power DC a speaker could handle has very little to do with how it
will live with music input.
Then there is the fact that not all 200 watt amps are the same.
You can NOT make anything idiot proof. The world just produces a better
idiot.
The only way I could see something like you want is a speaker/amp combo
with sensors on the speaker reporting back to the amp. It would detect
clipping and reduce the power. You could also have a thermal monitor which
cuts back if the speaker gets too hot. But there could still be clipped
waveforms coming off the mixer/preamp, you'd have to count on the thermal
monitor for that.
If the manufacturer has control over both amp and speaker it could be done.
Otherwise, your job as an engineer is to bulletproof the system yourself.
Not saying I want it that way, it's just real life.
George Gleason
>
> "George Gleason" <tbmo...@peoplepc.com> wrote in message
> news:mMyAg.7699$gF6....@newsread2.news.pas.earthlink.net...
>> I simply want a speaker that is rated at 200 watts to be ableto shed 200
>> watts of heating under ANY condition and ANY duty cycle
>> that wayI know if I put a 200 watt amp to a 300 watt speaker it will not
>> blow,ever regardless if I send it out with a pro guy or arni
>
> The world does not agree with you apparently.
>
> NOBODY has ever produced a speaker like that. Not JBL. not EV. Not the
> Europeans. NOBODY.
>
But I simply would likr to seperate the science from the marketing
don't call it music power call it'Ad copy power rateing"
George
Arny Krueger
> The problem is there is no word (sic) standard for speaker ratings.
Sure there is a world standard for speaker power ratings. There are several
of them. They are published and readily availble for the public to read. Any
loudspeaker manufacturer who so desires can pick an appropriate standard and
rate his equipment in accordance with it.
For example, there is AES2-1984 (r2003): AES Recommended Practice --
Specification of loudspeaker components used in professional audio and sound
reinforcement.
You can read it at
http://www.aes.org/publications/standards/courtesy.cfm?ID=12
GregS
There is more energy in a square wave. About twice the power. I don't dissagree. A 200 watt amp will usually
have at least a 56 volt rail. When you start to clip the rails start to drop rapidly.
If the rails managed to retain at least 50 volts the max DC or RMS power is about 300
watts. Your NOT going to blow the driver. If you started clipping a 600 watt amp, the driver will
get real hot.
greg
liquidator
If you had an engineering degree we would not be arguing. End of story, I am
done. It is all explained elsewhere in the thread.
GregS
I'm not arguing speaker power ratings. What I am saying, you are a lot more likely to blow it with a 600
watt amp, than a 200 watt amp.
Done.
liquidator
OK. Agreed. "Likely" I will agree with.
"Won't" is a different word.
George Gleason
> speaker.
> If you had an engineering degree we would not be arguing. End of story, I
> am
> done. It is all explained elsewhere in the thread.
>
that is rated to sell speaker, not deliver accurate infomation about the
speakers real ability to shed heat
George
George Gleason
> OK. Agreed. "Likely" I will agree with.
>
> "Won't" is a different word.
>
if you exceed those limits you get a blown speaker
if you stay under the REAL limits of the speaker it wont blow
Yoiu can take pure dc into a speaker and not blow it
it is not the clipping that blows the speaer
it is exceeding its limits that blow the speaker
you feed a pure square wave off a 1 watt amp into a 300 watt speaker , you
can do that nearly forever and the speaker will be just fine
the speaker will reproduce cluipped waves , square waves, sine wave any wave
you want without a care in the world until you exceed its heat sheading
ability
It is NOT the clipping that blows the speaker.
if it WAS the clipping than my example of the one watt amp driven into hard
clipping would destroy 1000 watt woofers
George
liquidator
George- you are just plain wrong. Why should a speaker be rated by it's DC
capability? NOBODY uses them that way!
You want the world to rate things your way because you just want it to. It
never has and never will.
It is NOT widespread industry practice. It is the ONLY industry practice.
Manufacturers do their best to provide a "real life rating'" To accuse
companies like JBL and Eminence, not to mention the rest of the entire
industry, of lying is just way off base.
The problem with a real life rating is your real life is one reality, mine
is another and there are billions more. There never will be a rating that
fits all situations.
An honest manufacturer will provide a rating and point out how it was
arrived at. If you want you can probably figure the duty cycle of pink noise
and figure out how to derate the speaker for how you are going to use it.
An entire industry is not lying. You are asking for a rating that would be
meaningless to 99% of the people. I doubt you could stay in business
satisfying one percent of the people. It just ain't gonna happen. Might as
well quit bellyaching and move on.
I am just plain done with this. Can we move on to something constructive
that will make you and I some money? I like it when people I know make
money. They can afford to buy me a decent beer.
George Gleason
>
> "George Gleason" <tbmo...@peoplepc.com> wrote in message
> news:cdLAg.9622$157....@newsread3.news.pas.earthlink.net...
>> > Greg, I simply won't argue with you. 300 watts can blow a 600 watt
>> > speaker.
>> > If you had an engineering degree we would not be arguing. End of story,
> I
>> > am
>> > done. It is all explained elsewhere in the thread.
>> >
>> only if the speaker is falsely rated, as is the industry wide practice<
>> that is rated to sell speaker, not deliver accurate infomation about the
>> speakers real ability to shed heat
>
> George- you are just plain wrong. Why should a speaker be rated by it's DC
> capability? NOBODY uses them that way!
>
> You want the world to rate things your way because you just want it to. It
> never has and never will.
> It is NOT widespread industry practice. It is the ONLY industry practice.
>
> Manufacturers do their best to provide a "real life rating'"
this is where we disagree
To accuse
> companies like JBL and Eminence, not to mention the rest of the entire
> industry, of lying is just way off base.
They are lying becuse everyone is lying
if they didn't lie nobody would buy thier product
I have a really good handle on what speaker can and can not do
and its NOT based on marketing pitches
>
> The problem with a real life rating is your real life is one reality,
> mine
> is another and there are billions more. There never will be a rating that
> fits all situations.
>
> An honest manufacturer will provide a rating and point out how it was
> arrived at. If you want you can probably figure the duty cycle of pink
> noise
> and figure out how to derate the speaker for how you are going to use it.
EV USED to do that
>
> An entire industry is not lying. You are asking for a rating that would be
> meaningless to 99% of the people. I doubt you could stay in business
> satisfying one percent of the people. It just ain't gonna happen. Might as
> well quit bellyaching and move on.
as I said one NEEDS to fabricate meaningless figures to sell product,
because everyone else does
THE FTC stepped in and forced HOME HIFI makes bto standardize power ratings
of HOME HIFI amp
why can this be done with PRO sound amps and speaker
if we can't get REAL rateing at least get standardized rateings so useful
comparisions can be made
>
>
> I am just plain done with this. Can we move on to something constructive
> that will make you and I some money? I like it when people I know make
> money. They can afford to buy me a decent beer.
I make more money using speakers that don't roll over dead with the first
blink of a clip light
George
GregS
>
>"George Gleason" <tbmo...@peoplepc.com> wrote in message
>news:cdLAg.9622$157....@newsread3.news.pas.earthlink.net...
>> > Greg, I simply won't argue with you. 300 watts can blow a 600 watt
>> > speaker.
>> > If you had an engineering degree we would not be arguing. End of story,
>I
>> > am
>> > done. It is all explained elsewhere in the thread.
>> >
>> only if the speaker is falsely rated, as is the industry wide practice<
>> that is rated to sell speaker, not deliver accurate infomation about the
>> speakers real ability to shed heat
>
>George- you are just plain wrong. Why should a speaker be rated by it's DC
>capability? NOBODY uses them that way!
DC is another thing. Its more likely to cause damage from hitting the back plate or just
completely comming off the pole piece.
greg
liquidator
>
> DC is another thing. Its more likely to cause damage from hitting the back
plate or just
> completely comming off the pole piece.
>
Nope and nope. ONLY if it is high enough amplitude and applied quickly
enough. You are picking one situation and making it general.
George wants to know what a speaker will sink with contiuous power (DC). A
useless rating for most people and situations. there simply is no need for
it.
Now if what you mean to say is that whenthere is DC present there is
usually a problem, we are in agreement
liquidator
>
> I make more money using speakers that don't roll over dead with the first
> blink of a clip light
Sigh. This simply has nothing to do with the discussion. I never suggested
you do or should.
And I never demeaned anything about your equipment.
This started as a speaker cannot be damaged by underpowering. It can. It
moved to ratings.
The pro stuff will not roll over and die at the blink of a clip light in any
sanely set up system, which is what you and I would own.
So that last comment has nothing to do with the discussion.
liquidator
Bullshit George. Duty cycle blows speakers. A one watt amp will not produce
enough duty cycle.
Are you completely ignoring every thing I said just because you don't WANT
to agree with it?
It is not black and white. At some point and amp being severely clipped will
produce enough duty cycle to blow the 1000 watt speaker. It will not take
1000 watts to do it.
An idiot can blow up your system. Therefore if an idiot turns one knob, your
system will certainly blow up no matter what knob he turns. That is the
argument you are making, and it doesn't hold water.
Just because clipping can damage speakers does not mean ANY level of
clipping will automatically do it.
You've said what you have to say. The rating you want will never happen
because it is useless. Let's end it.
George Gleason
I am happy to get out if you will admit ITS NOT THE CLIPPING that causes
speaker failure
all the clipping in the world will not damage your speaker until that
clipping exceeds the mechanical limits of the speaker
you can send a clipped singal into the speaker ALL FUCKING YEAR as long as
you do not generate enough heat (exceed the heat sheding ability of the
motor) you will not damage that speaker
its not the clipping its the heat
you can obtain dangerous heat with a clipped signal, you can also obtain
dangerous heat with a unclipped signal
and if your running 2x the recommend power into your speaker you have
severly reduced your saftey nargin
it is NOT SMART to run 2x the power into a speaker
buy the right sized amp and Dont over drive it
don't waste money buying a huge amp only to have to put massive limiting on
your system to keep the speakers intact
that is stupid
I have a speaker that is "rated" at 6000 watts peak
2400music 600 watts continueous
do you think for one second I would use a 4800 watt amp
no I use a 600 watt amp and can drive it to full output all day and night
without a worry in the world of power compression or heat failure
rcf 18l300 I believe though it may be the 18l800
it was the oem driver in the rcf event 1018 sub
george
George Gleason
>
> This started as a speaker cannot be damaged by underpowering. It can. It
> moved to ratings.
no it can't when you run a undersized amp into clipping you are putting out
much more than the rated wattage of the amp
the speaker sees this AS A BIGGER AMP
more volts, more heating
if you run a 300 watt speaker off a 100 watt amp and that amp NEVER puts out
more than 100 watts
the speaker WILL NOT BE DAMAGED
EVER if the speaker is honestly rated
the speaker doesn't give a rats ass about clipping, the movement of the
speaker is nearly insignificant in its heat sheding ability
send it pure square wave as long as you do not exceed its heat shedding
ability the speaker will not suffer heat damage, ever
george
george
George Gleason
if this is still on the forum monday I will continue to try to explain
thermal limits to you
I need to get to a gig
peace
george
Arny Krueger
> DC is another thing. Its more likely to cause damage from
> hitting the back plate or just
> completely comming off the pole piece.
Well-designed speakers won't damage themselves by hitting hard objects
inside the speaker. Instead, the motor will be designed so that the static
restoring force provided by the suspension overcomes any force generated by
the voice coil.
If a speaker has a Q > 0.707 (i.e., is less than critically damped) then
there will be some frequency > DC at which voice coil excursion will be
maximimized. IOW, in some cases the mass of the cone will cause the cone to
overshoot.
To minimize waranty claims, it is in the interest of the manufacturer to
make the speaker resistant to common kinds of user errors.
liquidator
>
> I am happy to get out if you will admit ITS NOT THE CLIPPING that causes
> speaker failure
> all the clipping in the world will not damage your speaker until that
> clipping exceeds the mechanical limits of the speaker
All the power in the world won't damage a speaker until it reaches its
mechanical limit.
Therefore power does not damage speakers.
A speaker may handle:
2000 watts with Musical program.
1000 with pink noise.
800 with 20% clipping.
500 with 80% clipping.
300 with 100% clipping.
100 watts steady state DC input.
You should know all this.
The speaker capable of handling 2000 watts will blow at 300 watts 100%
clipped. Give the speaker more power and it will live longer. Unless an
idiot throws 2000 watts at 80% clipping at it.
That same speaker may be able to handle 10,000 watts for a split second.
Duty cycle is power and time. Clipping will blow speakers in a much shorter
time than the same speaker fed a clean signal at the same power level. It is
because of the heavier duty cycle in clipped material.
No speaker will fail under any circumstances until its limits are reached. A
defective speaker simply has lower limits.
And speakers have a much lower limit with heavily clipped signals. YES
clipping can and does damage speakers.
I respect you to much do be doing this. Why are you beating a dead horse?
When what you said at the beginning of the thread was wrong, you mutated it
into this and are hanging onto it like a bulldog.
Business wise you are number one here in my book. I give you your props, you
have more than earned them. But sometimes you are a bit weak on the tech
end.
No insult meant. No one can be all things to all people.
liquidator
. A business manager trying to explain thermal limits to an engineer.
liquidator
>
> >
> > This started as a speaker cannot be damaged by underpowering. It can. It
> > moved to ratings.
>
> no it can't when you run a undersized amp into clipping you are putting
out
> much more than the rated wattage of the amp
> the speaker sees this AS A BIGGER AMP
> more volts, more heating
Wrong. An amp can never swing more volts. The power supply limits this. The
power can only stay on longer.
It is not a bigger amp. An amp cannot get bigger. It can only stay at full
power longer.
The speaker depends on the power going off to cool down. Without a break,
the heat builds and the speaker fails. Increase the on time and decrease the
off time, as in heavily clipped signals, and the speaker fails much faster.
Very basic stuff.
Clipping is not more voltage. The height of the wave is the representation
of voltage. It squares off the top because the voltage of the amp can go no
higher. It DOES stay at full power LONGER and that is the culprit.
BOB URZ
Arny Krueger wrote:
> "To minimize waranty claims, it is in the interest of the manufacturer to
> make the speaker resistant to common kinds of user errors."
So, all speakers should be built like M1 tanks?
Reality check Arny: Speakers are built at a price point.
Cheap speakers = cheap parts. You get what you pay for.
You might get lamps in series with HF drivers for some
limited protection. Or trade off low end for a stiffer cone
surround compliance and a little more margin for error.
The best protection circuit (and often defective) ever made
is the one between your ears.
Bob
----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==----
http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups
----= East and West-Coast Server Farms - Total Privacy via Encryption =----
liquidator
"BOB URZ" <"sound(remove)"@inetnebr.com> wrote in message
news:44D3D554...@inetnebr.com...
>
> So, all speakers should be built like M1 tanks?
> Reality check Arny: Speakers are built at a price point.
> Cheap speakers = cheap parts. You get what you pay for.
> You might get lamps in series with HF drivers for some
> limited protection. Or trade off low end for a stiffer cone
> surround compliance and a little more margin for error.
>
> The best protection circuit (and often defective) ever made
> is the one between your ears.
I've seen low end stuff with incredibly thick cones and stiff suspensions.
Certainly would handle power, but wasted a lot of your amplifier investment.
CerwinVega is one brand that comes to mind as often being optimized for
power handling.
Not saying evrything they have ever made was bad. There were bright spots.
But by and large it is a product line I'd never look at.
I agree about your comments on protection devices. If I get cabs with light
bulbs I usually cut them out. Haven't bought anything like that for years
though. .
Arny Krueger
>
> "George Gleason" <tbmo...@peoplepc.com> wrote in message
> news:8xNAg.9682$157....@newsread3.news.pas.earthlink.net...
>>
>> I am happy to get out if you will admit ITS NOT THE CLIPPING that causes
>> speaker failure
>> all the clipping in the world will not damage your speaker until that
>> clipping exceeds the mechanical limits of the speaker
Do you consider thermal breakdown to be a mechanical limit, or something
else?
Arny Krueger
>
>> "To minimize waranty claims, it is in the interest of the manufacturer to
>> make the speaker resistant to common kinds of user errors."
> So, all speakers should be built like M1 tanks?
No, because speakers are built for a variety of applications.
> Reality check Arny: Speakers are built at a price point.
That's a very incomplete view. Speakers are built for a purpose, part of
which could well be a price point. Or not. Every once in a while someone
gets despirate and says something like "I don't care what it costs, I just
want something that works!" The price becomes a range across a line, and
isn't a point anymore. So much for price points!
> Cheap speakers = cheap parts.
Sometimes, expensive speakers = cheap parts. That destroys your equality,
Bob.
>You get what you pay for.
Only if you are careful and/or lucky. That destroys your claim, Bob.
> You might get lamps in series with HF drivers for some
> limited protection. Or trade off low end for a stiffer cone
> surround compliance and a little more margin for error.
Stiff surrounds don't necessarily provide more margin for error. So much
for yet another false claim.
> The best protection circuit (and often defective) ever made
> is the one between your ears.
The world is full of speakers that can't possibly be damaged in use, so they
need no other protection than the environment in which they are designed to
operate. Another one of Bob's false claims bites the dust.
Bob Urz
Arny Krueger wrote:
> "BOB URZ" <"sound(remove)"@inetnebr.com> wrote in message
> news:44D3D554...@inetnebr.com...
>
>>
>>Arny Krueger wrote:
>>
>>
>>>"To minimize waranty claims, it is in the interest of the manufacturer to
>>>make the speaker resistant to common kinds of user errors."
>
>
>>So, all speakers should be built like M1 tanks?
>
>
> No, because speakers are built for a variety of applications.
>
>
>>Reality check Arny: Speakers are built at a price point.
>
>
> That's a very incomplete view. Speakers are built for a purpose, part of
> which could well be a price point. Or not. Every once in a while someone
> gets despirate and says something like "I don't care what it costs, I just
> want something that works!" The price becomes a range across a line, and
> isn't a point anymore. So much for price points!
>
The Charles Durning song in the "Best Little Whorehouse in Texas" comes
to mind. "Oh, how i love to do the side step"....
Do you have a clue what the term means?
>
>>Cheap speakers = cheap parts.
>
>
> Sometimes, expensive speakers = cheap parts. That destroys your equality,
> Bob.
>
So, cheap speakers don't have cheap parts Arny??? Lets say stamped frame
woofers Vs cast baskets. 1" voice coils Vs 4" coils. Piezo tweeters Vs
real compression drivers with replaceable voice coils. cheap wood boxes
vs 13ply+ baltic birch. glued butt joints Vs Flying hardware.
If you had a clue you would know. If you ever worked in a real sound
store you would know. If you worked as a real sound engineer you would
know.
>
>>You get what you pay for.
>
>
> Only if you are careful and/or lucky. That destroys your claim, Bob.
>
So you DON'T get what you pay for Arny????
That explains why Mackie and Behringer dominates the
"A" list concert touring business..... ;)
Of course, you don't have a clue about that end of the business.
Smart guys know better. Or ask someone who does.
>>You might get lamps in series with HF drivers for some
>>limited protection. Or trade off low end for a stiffer cone
>>surround compliance and a little more margin for error.
>
>
> Stiff surrounds don't necessarily provide more margin for error. So much
> for yet another false claim.
So why don't you think cheaper MI speakers don't have the low end
response of some higher priced units?
>
>>The best protection circuit (and often defective) ever made
>>is the one between your ears.
>
>
> The world is full of speakers that can't possibly be damaged in use,
ANYTHING can be damaged Arny. Perhaps you believe in Santa, the Easter
Bunny, and Radios shack tubes life time warranty. All it takes is a few
seconds of being careless or a electronics failure.
so they
> need no other protection than the environment in which they are designed to
> operate. Another one of Bob's false claims bites the dust.
>
>
Arny, you sure love to hear yourself talk on paper.....
I have had not much time to watch you hang yourself again.
Too busy doing a 3 week 12 million dollar John Deere dealer
convention. And sneaking in the Nationwide Tour Cox classic this
Sunday.
Earl Grey
opposed to musical input, but fourier analysis will tell you how much
extra power is being added in harmonics when a musical waveform is
clipped and its not really that significant. Its all above the fundamental.
However the loss of damping factor when an amp is clipping could have
some nasty effects.
Earl Grey
The IEC and EIA ratings that speaker manufacturers now specify are from
tests with a 6dB crest factor noise source which is limited by clipping
applied for a certain time period after which the speaker should not
show any damage.
The guys that established the standards are the ones that have to use
OEM drivers tested to that standard in their products, so its not really
in their interests for the spec to be meaningless fabricated bullshit
Pink noise is the normal envelope that music fits within, so its a fair
test, it relates to normal system usage like a dynamometer test
relates to driving a car.
Earl Grey
clipping is a type of gain reduction like limiting, so the average level
is increased ie the voltage gain is still increasing as the amp is
progressively overdriven.
Its the average level, not the shape of the top of the waveform that
heats the voicecoil.
liquidator
"Earl Grey" <e...@t.pot> wrote in message news:44d46d4d$1...@clear.net.nz...
> >
> That may be partially true if the amp is being fed by a tone source as
> opposed to musical input, but fourier analysis will tell you how much
> extra power is being added in harmonics when a musical waveform is
> clipped and its not really that significant. Its all above the
fundamental.
> However the loss of damping factor when an amp is clipping could have
> some nasty effects.
It is not harmonics. You obviously are not a trained engineer.
In a representation of a wave, the hight indicates amlitude. The horizontal
indicates time.
The amp hits it's power cieling and as long as the am is being driven to
full, STAYS THERE.
The power stays at full longer. The speaker heats.
Had you bothere to study you would have covered this in your first year.
The problem is neither you or George have ANY professional training. You are
either repating what someone told you, you read somewhere, or found on
Usenet. You got bad info, never verified it with a knowlegeable source. And
are now repeating it.
liquidator
"Earl Grey" <e...@t.pot> wrote in message news:44d47836$1...@clear.net.nz...
You are sorta right, bit wrong from an engineering standpoint. The amp has
no gain reduction. It simply runs out of power. It is pushed to it's
capability and held there.
George says the amp gets bigger and puts out more power. It cannot.
All it can do is putout it's full power contiguously. This is why a severely
clipped amp will thermal.
I said, if you bother to read what I have posted, that the duty cycle is
what blows the speaker. A continuously clipped amp is putting out more power
or a longer time That is duty cycle. Sounds a lot like what you are calling
average power. You are just quibbling semantics on this one.
However you totally leave out an important design point.
Power and TIME.
If you look at a representation of a sound wave, it is full of peaks and
valleys. The peaks represent power applied, then it fades.
When an amp is driven to clipping, the valleys disappear.
The speaker is gaining heat when power is applied- basic physics.
It loses heat the whole time. there are off period when there is no heat
input to the speaker. The speaker is designed to need this.
Drive the amp to severe clipping, and the valleys disappear. There is no
"down time" where the speaker gets a chance to recover. You are close to
right, thecnically, by calling this compression. But is is a very severe
form of it.
With almost constant power being applied, the speaker never cools down.
do you begin to see? A speaker can fail at a lower power with the amp driven
to severe clipping.
Give the speaker a clean amp and give it the same amount of power. Only it
is peaks and valleys, the same amount of average power. The speaker has no
problem handling brief transients., as long as it gets a break to lose heat.
It will in this case.
Same amount of average power, but the duty cycle (on/off power) is more
intermittent.
Speaker devices are designed to handle intermittent power, not continuous.
They are designed to reproduce waveforms of that sort.
liquidator
"Earl Grey" <e...@t.pot> wrote in message news:44d4737d$1...@clear.net.nz...
We mostly agree here. I have been trying to communicate to George that ANY
test is not real life usage, at best just gives you starting info,
The standards you mention are actually far from standard. Many Pro gear
manufacturers simply do not use them.
So I have to completely disagree with the statement manufacturers specify
those ratings. Many high quality manufacturers do not.
liquidator
Earl, let me apologise for the tone her. After reading it, it comes acroos
much harsher than I intended.
Hank posted elswhere, the written word often comes across harsher, since
you lose the other person's body language and tone of voice.
But please rad the entire thread,. AT NO POINT do I say it is harmonics
that is the problem. that is a Usenet fallacy.
The problem is a combination of the power and how long it stays on without a
break. speakers are simply not designed for the power to stay on. operate a
device outside it's design parameters and you get early failure THAT is all
I am saying. Conversations with engineers at Beyma and Eminence conform what
I have said in this thread. I am not making this up.
From George's replies it's obvious he isn't reading everything. He has his
mind made up and is defending it like a bulldog.
It's so important to him to BE right that he has lost track of everything
else.
liquidator
finger typists.
Saxology
to put this into a slightly different light:
1. At a given amplitude, a DC waveform has more energy and power. When you
clip at a given amplitude your amp puts out more power (if it can, else, the
amplitude drops).
2. Clipping can happen due to power supply, output signal rail capability,
or in the small signal chain where a distirted (clipped) signal is
generated. If the clipping happen early in the signal chain your amp will
most likely be able to deliver the clipped signal to the load.
3. Frequency matters to a speaker. A coil is a short to DC, a capacitor is
like an open circuit. So, at 0Hz the impedance of the speaker drops. So,
at a given amplitude signal, the power dissipation soars. Without any
limiting resistor or crossover network the current goes to infinity and so
does the power which will burn the coil fast.
I have over simplified this a bit but the basics are that the bandpass of
the driver can't be ignored. This is why the rating, without bandpass, is a
bit thin. Many crossovers roll off the base at the lowest frequencies just
to save the foolish user from the fate that lies before him after a DC
reinforcement.
-Sax
Saxology
<snip>
>
> If its just a sub, clipping is not going to do a lot. The harmonics fall
> up into the
> region where the sub is significantly higher than the rated Z. If there
> are pasive mids and highs, thats another story.
>
> greg
>
<snip>
I think you are reacting to the claim that going from AC signal to a DC
signal creates harmonics of a higher frequency which "fills in the wave
form". FFT analysis aside, and will all due respect to all of the engineers
here, I would simply argue that DC id ZERO (0) Hz. It is a low frequency,
not a high one. It is the low frequency component that is the bothersome
one, not the audiofile 75KHz one that makes those cymbals crispier (cuz they
can hear it, really they can!).
-Sax
Saxology
>
> There is more energy in a square wave. About twice the power. I don't
> dissagree. A 200 watt amp will usually
> have at least a 56 volt rail. When you start to clip the rails start to
> drop rapidly.
> If the rails managed to retain at least 50 volts the max DC or RMS power
> is about 300
> watts. Your NOT going to blow the driver. If you started clipping a 600
> watt amp, the driver will
> get real hot.
>
> greg
You should note that you are addressing a clip in the output stage of the
amplifier only, when it hits its rail. A clip generated in the
mixer/processing due to a rail hit might be as deadly given the impedance
seen by the amp and its ability to deliver current at that impedance.
Also, this is why some speaker designs use a blocking cap to attenuate the
DC to 0. The problem: lower frequence performance will suffer as nearby
frequencies are also attenuated.
-Sax
Saxology
<snip>
>
> All the power in the world won't damage a speaker until it reaches its
> mechanical limit.
> Therefore power does not damage speakers.
>
<snip>
watch out dude, you are using Arny logic. If it isn't power (voltage and
current) that damages speakers (and ya don't run over 'em wit yer pickup),
then just what does? Can you clip one without any power? I wanna see that!
-Sax
Saxology
> speaker.
Nope. If the speaker is rated for 600 watts at 0Hz then 300 watts at 0Hz
will be fine. It meets the spec.
>> only if the speaker is falsely rated, as is the industry wide practice<
>> that is rated to sell speaker, not deliver accurate infomation about the
>> speakers real ability to shed heat
It is not that it is falsely rated, it is that the rating at 0Hz isn't used
because you aren't supposed to do that.
>
> George- you are just plain wrong. Why should a speaker be rated by it's DC
> capability? NOBODY uses them that way!
True enough, but care must be taken somewhere: signal chain, amplifier power
limit, or filtering at the speaker to prevent such occurances. We wouldn't
rate a single driver by it's DC performance but when coupled with a
crossover we could. For those using a single driver, no crossover, they
better take care in their mixing/processing to ensure that clipping doesn't
occur. The power rating and impedance for a speaker driver is specified
over a "bandwidth". That part of the spec must be adhered to. If the
rating is 1000w at 1khz and 2w at DC, then 2 watts will blow your "1000w
advertised" driver.
<snip>
>
> An entire industry is not lying. You are asking for a rating that would be
> meaningless to 99% of the people. I doubt you could stay in business
> satisfying one percent of the people. It just ain't gonna happen. Might as
> well quit bellyaching and move on.
Low frequence impedance of the speaker is important to designers.
-Sax
Saxology
>
> "George Gleason" <tbmo...@peoplepc.com> wrote in message
> news:KBNAg.9683$157....@newsread3.news.pas.earthlink.net...
>>
>> >
>> > This started as a speaker cannot be damaged by underpowering. It can.
>> > It
>> > moved to ratings.
>>
>> no it can't when you run a undersized amp into clipping you are putting
> out
>> much more than the rated wattage of the amp
>> the speaker sees this AS A BIGGER AMP
>> more volts, more heating
>
> Wrong. An amp can never swing more volts. The power supply limits this.
> The
> power can only stay on longer.
The amplifier can limit because of current or voltage, both are issues with
the design and usually rest in the power supply arena.
>
> It is not a bigger amp. An amp cannot get bigger. It can only stay at full
> power longer.
>
> The speaker depends on the power going off to cool down. Without a break,
> the heat builds and the speaker fails. Increase the on time and decrease
> the
> off time, as in heavily clipped signals, and the speaker fails much
> faster.
Not all thermal problems create the "run away thermal" that you describe.
You concept that AC provides a peak power and then no power is sound but,
really, RMS is the power you need to watch. It is the power that generates
the thermal rise that exists until the signal is eliminated.
-Sax
liquidator
"Saxology" <saxolo...@yahoo.com> wrote in message
news:4K2Bg.10117$157....@newsread3.news.pas.earthlink.net...
1 Clipping is not DC. It does not matter if the coil is a short to DC. And
is is not anyway. It still has it's DC resistance, usually 5 or 6
ohms. A coil is never a short to anything unless it is shorted. DC
resistance of a coil is only a little less than its impedance.
2 The discussion was about power amp clipping damaging speakers. The
problem is that the amp is driven to it's limit and held there. The speaker
can handle signal chain clipping a bit better than it can handle a severely
clipped power amp.
You are sort of correct about the power, the culprit is power and time. BTW
when you clip you have no more amplitude. The definition of clipping is that
you have run out. The only thing you can do is hold the amp at that
amplitude. You can not drive it higher. George claims an amp puts out more
voltage when it's clipped. There is no more voltage to put out.
The power is held high for a long time. The speaker has no break to shed
heat, it accumulates, and the speaker will fail early.
With a bigger amp, the same amount of power will have peaks and valleys. The
valleys give the speaker a chance to lose heat.
So with a bigger amp, a speaker can survive longer at the same average
power. It is a matter of how the power is applied. Intermittently rather
than continuously.
You can use a 2000 watt amp with a speaker rated 1000 watts. Just don't clip
it.
Hope this makes sense- I am really trying to get this across.
There are lots of other things that enter the picture. But this is the
basics.
liquidator
Again DC is not clipping. Clipping certainly has a DC component, as does a
sine wave.
Blocking caps have fallen out of favor. Do a search over at Pro Sound Web.
There are good discussions there, no need to repeat them.
Most pro manufactureres, including EAW, say not to use them. They remove
the power amp's damping from the driver.
The discussion started as how much power a speaker can handle, which is why
all of us are talking about power amp clipping.
The discussion was about power amp clipping and how it affects speakers.
Generally, preamp clipping is not as dangerous as power amp clipping. now if
you are diving the power amp to hard clip with a heavily clipped preamp
signal, all bets are off ;-)
liquidator
Again, clipping is NOT zero hz and NOT DC.
The problem is power, and how long it's held high.
liquidator
> > 300 watts can blow a 600 watt
> > speaker.
>
> Nope. If the speaker is rated for 600 watts at 0Hz then 300 watts at 0Hz
> will be fine. It meets the spec.
>
Absolutely positively wrong SAx. Show me one speaker rateed 300 watts at 0
hz. You can not, simply because it doe not exist.
>
> > George- you are just plain wrong. Why should a speaker be rated by it's
DC
> > capability? NOBODY uses them that way!
>
> True enough, but care must be taken somewhere: signal chain, amplifier
power
> limit, or filtering at the speaker to prevent such occurances. We
wouldn't
> rate a single driver by it's DC performance but when coupled with a
> crossover we could. For those using a single driver, no crossover, they
> better take care in their mixing/processing to ensure that clipping
doesn't
> occur. The power rating and impedance for a speaker driver is specified
> over a "bandwidth". That part of the spec must be adhered to. If the
> rating is 1000w at 1khz and 2w at DC, then 2 watts will blow your "1000w
> advertised" driver.
>
>
Again, speakers are not rated at DC because thay are NOT used that way.
liquidator
was replying to, it will become clearer. He said clipping doesn't damage a
speaker until it reaches it's mechanical limit. True enough. the clipping
just helps the speaker reach it's limit earlier.
If clipping does not damage speakers according to that logic, neither does
power.
And of course no one is going to dispute that power can damage a speaker.
Parody out of context loses its irony.
liquidator
DUTY cycle- the off on cyle- is what has to be watched. I posted a situation
elsewhere in this thread where two amps can put out the same amount of
average power and one can damage the speaker, another won't.
You have the right idea. Just wrong in engineering terms.
I did not state that all situations lead to thermal runaway. Please show
where I did, if you think I said that.
I said that thermal runaway can occur at much less than the speaker's rated
power under the proper conditions. George says it can't. He's wrong.
Again. the culprit is power and time, and that in one situation the power is
more continuous than the other.
Continuous power will make a speaker fail quicker than intermittent power,
if only because the speakers are designed for intermittent power and not
continuous.
None of this is absolute. A speaker can stand a certain amount of continuous
power, just less of it.
Saxology
<snip>
> 1 Clipping is not DC. It does not matter if the coil is a short to DC.
> And
> is is not anyway. It still has it's DC resistance, usually 5 or 6
> ohms. A coil is never a short to anything unless it is shorted. DC
> resistance of a coil is only a little less than its impedance.
Try looking up "inductance" in your electronics book. Look at the complex
form of the impedance. You will discover that an inductor has no resistive
component to the term (Real component), only imaginary. The only resistance
found in a coil is due to the fact that there is parasitic resistance to the
wire, if not for that the real component would be, zero.
If the impedance of a coil is nearly purely resistive as you claim, it is a
resistor with parasitic inductance. A perfect reisitor has no imaginary
term in its impedance. My be that your coils have no inductance.... you
might want to inform the coil winders of this problem as they are really
trying to create something quite different.
-Sax
Saxology
George has real world experience to back up his claims. If his real world
experience is true, then the facts (scientifically) should support what he
says. I believe that, without adding foolish detail, George is basically
correct. You may have misunderstood some of what he claimed because it
looks to me like you think that the only damage is a mechanical damage to
the driver movement (your understanding od his claim). I don't think he
really meant that at all. Thermal properties are "mechanical", or in the
realm of mechanical engineering. It is where the electricals and
mechanicals get to meet (and fight some). What george is stating, I think,
is that as long as the driver specification is met, no problems will occur.
When it is not met, for any reason, problems arise. He also claims that
marketing genius often "water down" or stretch the truth (often by leaving
out important spec data) when rating speakers and that presents a problem
for system designers like himself.
-Sax
Saxology
<snip>
> DUTY cycle- the off on cyle- is what has to be watched. I posted a
> situation
> elsewhere in this thread where two amps can put out the same amount of
> average power and one can damage the speaker, another won't.
You are talking about AC waveforms where the average amplitude is 0
(exactly). If the average is not zero, DC exists.
Your only claim is that peak power for 2 amps can be different, so what. If
you violate the peak power spec for a driver...poof, simple as that.
Your other claim, which you keep inferring, is that all coils don't burn up
instatnaneously. Who really cares? The fact that some take a bit longer,
under out of spec stress, to burn up is uninteresting. And the fact that
you can take a cold device and run its temperature up by over driving it for
a longer burst rather than a short one for a hotter component is still
uninteresting (duty cycle). The fact is that the thermal limit is the
thermal limit.
>
> You have the right idea. Just wrong in engineering terms.
>
> I did not state that all situations lead to thermal runaway. Please show
> where I did, if you think I said that.
You claim of duty cycle does that. If at 100% duty cycle the component
burns it is in a thermal run away situation. So, you are running the
component out of limit. The fact that you can refrigerate it (or use it on
a cold day) doesn't change that. You whole duty cycle thing is pure hog
wash. What you are doing is nothing more than running a component past its
limits and then cooling it down to help preserve the integrity. You should
use RMS power for heat calculations, that is all the duty cycle you need (or
get for that matter).
>
> I said that thermal runaway can occur at much less than the speaker's
> rated
> power under the proper conditions. George says it can't. He's wrong.
Not really, you are saying that a device that can dissipate 30 watts will
burn up with 20 watts but not 40 watts. Sorry, sell that to arny.
>
> Again. the culprit is power and time, and that in one situation the power
> is
> more continuous than the other.
RMS is the answer. In cases where peak power doesn't damage the device
(physically), your only claim is that it takes time to heat something up.
And, if you cool it down before it gets too hot you saved it. So, all you
are claiming is that RMS power is the spec you should be using when doind
electrical design... is says the same thing....
>
> Continuous power will make a speaker fail quicker than intermittent power,
> if only because the speakers are designed for intermittent power and not
> continuous.
You design for continuous, because that is all there is. Anything else is
useless specmanship.
I think you are confused about peak power (relatively uninteresting) and
RMS.
-Sax
Saxology
>
> "Saxology" <saxolo...@yahoo.com> wrote in message
> news:gb3Bg.4245$xp2....@newsread1.news.pas.earthlink.net...
>> > 300 watts can blow a 600 watt
>> > speaker.
>>
>> Nope. If the speaker is rated for 600 watts at 0Hz then 300 watts at 0Hz
>> will be fine. It meets the spec.
>>
>
>
> Absolutely positively wrong SAx. Show me one speaker rateed 300 watts at 0
> hz. You can not, simply because it doe not exist.
You are a fool! my fact is 100% correct. The fact that you don't have such
a speaker in your hand is uninteresting. The simple fact is that a coil is
a short for DC, that is why they don't let ya run 'em at DC!
>>
>> > George- you are just plain wrong. Why should a speaker be rated by it's
> DC
>> > capability? NOBODY uses them that way!
>>
>> True enough, but care must be taken somewhere: signal chain, amplifier
> power
>> limit, or filtering at the speaker to prevent such occurances. We
> wouldn't
>> rate a single driver by it's DC performance but when coupled with a
>> crossover we could. For those using a single driver, no crossover, they
>> better take care in their mixing/processing to ensure that clipping
> doesn't
>> occur. The power rating and impedance for a speaker driver is specified
>> over a "bandwidth". That part of the spec must be adhered to. If the
>> rating is 1000w at 1khz and 2w at DC, then 2 watts will blow your "1000w
>> advertised" driver.
>>
>>
>
> Again, speakers are not rated at DC because thay are NOT used that way.
That is george's point, you just don't understand it. Besides, they protect
them (where possible) so that the effects of DC are minimized.
-Sax
Saxology
Unless you can't follow the conversation: wer are discussing the difference
between AC (no clip) performance and performance under a clipped signal.
And, for the record, there is no DC component to a sine wave, period, enf of
story. The average value of a sine wave is ZERO. There is no room for DC
in the pro audio guy's world... we eliminate it.
>
> Blocking caps have fallen out of favor. Do a search over at Pro Sound Web.
> There are good discussions there, no need to repeat them.
I was using a simplified example.... try to follow along....
>
> Most pro manufactureres, including EAW, say not to use them. They remove
> the power amp's damping from the driver.
>
> The discussion started as how much power a speaker can handle, which is
> why
> all of us are talking about power amp clipping.
That is because when you clip RMS power increases which impacts your speaker
expecially if you use an amp more than capable of delivering the power.
>
> The discussion was about power amp clipping and how it affects speakers.
>
> Generally, preamp clipping is not as dangerous as power amp clipping. now
> if
> you are diving the power amp to hard clip with a heavily clipped preamp
> signal, all bets are off ;-)
Nice try, but no. The clipped waveform is the same, the difference is that
the power amp can deliver the current to the load where in the case of the
amp's limit being reached your RMS value increases but the amp has a hard
time delivering.... the reason the amp may overheat first.
-Sax
Saxology
-Sax
liquidator
>
> "liquidator" <liqui...@collide.org> wrote in message
> news:44d4bb50$0$22576$8826...@free.teranews.com...
> <snip>
>
> > DUTY cycle- the off on cyle- is what has to be watched. I posted a
> > situation
> > elsewhere in this thread where two amps can put out the same amount of
> > average power and one can damage the speaker, another won't.
>
> You are talking about AC waveforms where the average amplitude is 0
> (exactly). If the average is not zero, DC exists.
> Your only claim is that peak power for 2 amps can be different, so what.
If
> you violate the peak power spec for a driver...poof, simple as that.
Show where I said that. I never mentione peak power once. I said two amps
can put out the same average power, and one burn the speaker and the other
not
> Your other claim, which you keep inferring, is that all coils don't bu
rn up
> instatnaneously.
You just said my only claim, then said another. I said neither of the things
in your fantasy.
> >
> > I did not state that all situations lead to thermal runaway. Please show
> > where I did, if you think I said that.
>
> You claim of duty cycle does that.
ROTFL. bullshit.
If at 100% duty cycle the component
> burns it is in a thermal run away situation.
You said that I didn't. Qoute where I said that.
So, you are running the
> component out of limit. The fact
that you can refrigerate it (or use it on
> a cold day)
Since you think it's a fact that I said that, show where I did. I said
nothing about cold days or refrigeration, You did.
. You should
> use RMS power for heat calculations, that is all the duty cycle you need
(or
> get for that matter).
S-N-O-R-E There is still a duty cycle, calculate it all you want..
Measuring it is more accurate.
> >
> > I said that thermal runaway can occur at much less than the speaker's
> > rated
> > power under the proper conditions. George says it can't. He's wrong.
>
> Not really, you are saying that a device that can dissipate 30 watts will
> burn up with 20 watts but not 40 watts. Sorry, sell that to arny.
Show where I said that. I said device ratings change with the type of
signal. They do.
>
> >
> > Again. the culprit is power and time, and that in one situation the
power
> > is
> > more continuous than the other.
> RMS is the answer. In cases where peak power doesn't damage the device
> (physically), your only claim is that it takes time to heat something up.
> And, if you cool it down before it gets too hot you saved it. So, all you
> are claiming is that RMS power is the spec you should be using when doind
> electrical design... is says the same thing....
RMS power has cyles of power off and on Sax...
>
> >
> > Continuous power will make a speaker fail quicker than intermittent
power,
> > if only because the speakers are designed for intermittent power and not
> > continuous.
>
> You design for continuous, because that is all there is. Anything else is
> useless specmanship.
>
You are confusing RMS with continuous signal. RMS ratings are usually
measured with pink noise. Pink noise is not continuous.
> I think you are confused about peak power (relatively uninteresting) and
> RMS.
Sax- you are incredibly confused on a number of issues. I never mentione
peak power anywhere. YOU did.
All amp ratings I specified were the RMS ratings of the amps.
Have a nice life.
liquidator
Most of the detail you've adde has been foolish.
. You may have misunderstood some of what he claimed because it
> looks to me like you think that the only damage is a mechanical damage to
> the driver movement (your understanding od his claim).
Then why was I talking about burned coils?
I don't think he
> really meant that at all. Thermal properties are "mechanical", or in the
> realm of mechanical engineering. It is where the electricals and
> mechanicals get to meet (and fight some). What george is stating, I
think,
> is that as long as the driver specification is met, no problems will
occur.
And the driver is not rated for 100% clipping. no drivers are, You lose this
one too.
> When it is not met, for any reason, problems arise. He also claims that
> marketing genius often "water down" or stretch the truth (often by leaving
> out important spec data) when rating speakers and that presents a problem
> for system designers like himself.
I understand those problems. Often you have to interpret ratings. It helps
when the ratings are described.
Sax- I have been doing sound since the 1960's. I worked for Altec Lansing.
I have real world experience. Much more than you. In fact I have been doing
this longer than George. You went there- I didn't.
Have a nice life.
liquidator
>
> "liquidator" <liqui...@collide.org> wrote in message
> news:44d4b455$0$22565$8826...@free.teranews.com...
> <snip>
>
> > 1 Clipping is not DC. It does not matter if the coil is a short to DC.
> > And
> > is is not anyway. It still has it's DC resistance, usually 5 or 6
> > ohms. A coil is never a short to anything unless it is shorted. DC
> > resistance of a coil is only a little less than its impedance.
>
> Try looking up "inductance" in your electronics book. Look at the complex
> form of the impedance. You will discover that an inductor has no
resistive
> component to the term (Real component), only imaginary. The only
resistance
> found in a coil is due to the fact that there is parasitic resistance to
the
> wire, if not for that the real component would be, zero.
>
> If the impedance of a coil is nearly purely resistive as you claim, it is
a
> resistor with parasitic inductance.
Are you on drugs? You said short at DC, I said DC resistance.
You said a coil presented a short at DC. Look back and see. I proved you
wrong.
A perfect reisitor has no imaginary
> term in its impedance. My be that your coils have no inductance.... you
> might want to inform the coil winders of this problem as they are really
> trying to create something quite different.
Sax . I never said 90% of the stuff you said in your posts.
liquidator
>
> "liquidator" <liqui...@collide.org> wrote in message
> news:44d4b61e$0$22530$8826...@free.teranews.com...
> >
a
> > sine wave.
>
> Unless you can't follow the conversation: wer are discussing the
difference
> between AC (no clip) performance and performance under a clipped signal.
> And, for the record, there is no DC component to a sine wave, period, enf
of
> story. The average value of a sine wave is ZERO. There is no room for DC
> in the pro audio guy's world... we eliminate it.
>
Sax you lose. there is a DC component in a sine wave. And clipping is NOT
DC!
> >
> > Blocking caps have fallen out of favor. Do a search over at Pro Sound
Web.
> > There are good discussions there, no need to repeat them.
>
> I was using a simplified example.... try to follow along....
>
Nope. A simple example..
>
> Nice try, but no. The clipped waveform is the same
As what? the compaison is between a clipped and non clipped amp. You can't
read Sax.
, the difference is that
> the power amp can deliver the current to the load where in the case of the
> amp's limit being reached your RMS value increases but the amp has a hard
> time delivering.... the reason the amp may overheat first.
Close but no cigar. Sax you could not even pass a first year engineering
test.
liquidator
Sax- you still are not reading. George is the one wanting a DC rating. I
said it would be useless. Reread the entier thread. You are looking foolish.
And most of it is not my doing.
Saxology
>
> "Saxology" <saxolo...@yahoo.com> wrote in message
> news:YJ7Bg.4433$xp2....@newsread1.news.pas.earthlink.net...
>>
>> "liquidator" <liqui...@collide.org> wrote in message
>> news:44d4b455$0$22565$8826...@free.teranews.com...
>> <snip>
>>
>> > 1 Clipping is not DC. It does not matter if the coil is a short to DC.
>> > And
>> > is is not anyway. It still has it's DC resistance, usually 5 or 6
>> > ohms. A coil is never a short to anything unless it is shorted. DC
>> > resistance of a coil is only a little less than its impedance.
>>
>> Try looking up "inductance" in your electronics book. Look at the
>> complex
>> form of the impedance. You will discover that an inductor has no
> resistive
>> component to the term (Real component), only imaginary. The only
> resistance
>> found in a coil is due to the fact that there is parasitic resistance to
> the
>> wire, if not for that the real component would be, zero.
>>
>> If the impedance of a coil is nearly purely resistive as you claim, it is
> a
>> resistor with parasitic inductance.
>
>
> Are you on drugs? You said short at DC, I said DC resistance.
reactive load not resistive. You have stated that a piece of bare copper
wire is 5-6 ohms and I said it is a short. Try testing a piece of wire with
a meter and I think you will find it is a short. A DC short. A cap is a DC
open circuit (hence why they call it a DC BLOCKING CAP) not a resistor.
>
> You said a coil presented a short at DC. Look back and see. I proved you
> wrong.
Yes I did and you are wrong. If you have proven that a piece of wire can't
short out a DC power supply you should write a book with arny. You can
state it again but you still will be wrong. If you have an electronics book
look up the impedance of a coil. The answer is 0+jwl, at a given frequency.
At DC (w=0) it would be equal to 0+0 which, here in the US is 0. A cap is
0+1/jwc so that at DC (w=0) the magnitude of impedance is infinite (open
circuit). okey dokey for the engineering info on that one? Now, I have
given the equations and have shown how they support my facts. If you have
proven these wrong you really need to write that book.
The only reason reactive loads have any real (R) portion of impedance is
because they can't be made perfectly. Kind of like you!
>
> A perfect reisitor has no imaginary
>> term in its impedance. My be that your coils have no inductance.... you
>> might want to inform the coil winders of this problem as they are really
>> trying to create something quite different.
>
> Sax . I never said 90% of the stuff you said in your posts.
why yes you did, in fact you have restated it in this post that the DC value
of a coil is 5-6 ohms. Therefore, the reactive load is less for a 4 ohm
load making your coil, BY DEFINITION, a resistor with a paracitic
inductance.
You shouldn't repeat things many times and then claim not to have said them.
It is just plain foolish.
-Sax
Saxology
><snip>
>
> I don't think he
>> really meant that at all. Thermal properties are "mechanical", or in the
>> realm of mechanical engineering. It is where the electricals and
>> mechanicals get to meet (and fight some). What george is stating, I
> think,
>> is that as long as the driver specification is met, no problems will
> occur.
>
> And the driver is not rated for 100% clipping. no drivers are, You lose
> this
> one too.
Sorry skippy, you proved my point. At 100% DC clip you have a short....
that's why they don't let ya do it. Its a coil. If it were a resistor,
like you claim, it wouldn't care about the clipping or the DC.... get the
idea yet? Try not to prove my point in your next post, it is just too
foolish.
>
>> When it is not met, for any reason, problems arise. He also claims that
>> marketing genius often "water down" or stretch the truth (often by
>> leaving
>> out important spec data) when rating speakers and that presents a problem
>> for system designers like himself.
>
> I understand those problems. Often you have to interpret ratings. It helps
> when the ratings are described.
>
>
> Sax- I have been doing sound since the 1960's.
Time to go back to school or get some aricept. You got problems.
I worked for Altec Lansing.
Ah yes, had some of those speaks on my HiFi PC. Good work I'm sure.
> I have real world experience. Much more than you.
Hate to do this to you, but, how much have I had? To make that comment you
have to know that. Smarter than you I have proved. But experience you must
now prove.
> In fact I have been doing
> this longer than George. You went there- I didn't.
Being old doesn't mean that you know anything. Being old doesn't make you
wise. Being old only means that you have sucked more wind that people
younger than yourself. Age just doesn't mean crap. You either know what
you are talking about or you don't. I'll give you that you may know more
than most about testing tubes on the old tube tester at radio shack but
since I have solid state electronics and Radidio Shark got rid of its tube
tester decades ago that huge bank of old school knowledge is, basically,
worthless.
-Sax
liquidator
>
> "liquidator" <liqui...@collide.org> wrote in message
> news:44d50e28$0$22492$8826...@free.teranews.com...
> ><snip>
>
>
>
> Ah yes, had some of those speaks on my HiFi PC. Good work I'm sure.
>
>
>. Smarter than you I have proved.
You have proved nothing but zero knowledge and the ability to run your
mouth.
Saxology
>
> "Saxology" <saxolo...@yahoo.com> wrote in message
> news:L38Bg.184$Qf...@newsread2.news.pas.earthlink.net...
>>
>> "liquidator" <liqui...@collide.org> wrote in message
>> news:44d4bb50$0$22576$8826...@free.teranews.com...
>> <snip>
>>
>> > DUTY cycle- the off on cyle- is what has to be watched. I posted a
>> > situation
>> > elsewhere in this thread where two amps can put out the same amount of
>> > average power and one can damage the speaker, another won't.
>>
>> You are talking about AC waveforms where the average amplitude is 0
>> (exactly). If the average is not zero, DC exists.
>
>> Your only claim is that peak power for 2 amps can be different, so what.
> If
>> you violate the peak power spec for a driver...poof, simple as that.
>
> Show where I said that. I never mentione peak power once. I said two
> amps
> can put out the same average power, and one burn the speaker and the other
> not
Ok, then, without using the term On, off, peak, valley, high, low.... how do
you get 2 RMS powers to be the same but one has the capability to burn the
load. Don't say that the duty cycle is different because to get the same
average the shorter duty cycle has to have the higher PEAK, other wise the
average would be less. Go ahead, use some math and make it abundantly clear
for every one. You don't mention the word peak because you don't understand
it. You talk about the "high" (which would be the peak) and the low (zero
volts) to average power/heat. While you don't know the proper terminology,
I gave it to you free. But, please, try using you own words to explain it,
without a peak. Remember, you have stated the High voltage doesn't change,
only time.... hmmmmm but the average over time stays the same...all the time
too! Good lluck, it will be an informative chapter in your arny co-authored
electronics book.
>
>> Your other claim, which you keep inferring, is that all coils don't bu
> rn up
>> instatnaneously.
>
> You just said my only claim, then said another. I said neither of the
> things
> in your fantasy.
Semantics.... but if you learn to read you will see that I respond to
different things in different places. You need to follow the conversation.
Kind of hard, like your arteries! And, in my fantasy you aren't even
around. You claimed coils butning up and time. Which means that you
forgave instantaneous. Simple conclusion, not that you can understand it.
Face it, you have no clue. All you do now is try to attack semantics which
shows that you are pretty sorry.
>
>
>
>> >
>> > I did not state that all situations lead to thermal runaway. Please
>> > show
>> > where I did, if you think I said that.
>>
>> You claim of duty cycle does that.
>
>
> ROTFL. bullshit.
>
>
> If at 100% duty cycle the component
>> burns it is in a thermal run away situation.
>
> You said that I didn't. Qoute where I said that.
You said duty cycle... you said it can't be 100%.... if it doesn't run away
at any % it can be 100%. You say it, but you don't realise what you say.
You are an idiot.
>
> So, you are running the
>> component out of limit. The fact
> that you can refrigerate it (or use it on
>> a cold day)
>
> Since you think it's a fact that I said that, show where I did. I said
> nothing about cold days or refrigeration, You did.
You said highs (not peaks because you couldn't find a peak) which heats the
coil. Then you said duty cycle to allow for cooling (refrigeration, but you
most likely would use the term "ice boxing" or fridgidaireing) The fact
that I use words that are not the exact same as yours I did on purpose
because repeating what you said you already did and you are wrong. That is
why, when people respond, the use correct terms and words. When you are
wrong you have little chance they will tell you what you want to hear....
it's your old age creeping up on you....
>
> . You should
>> use RMS power for heat calculations, that is all the duty cycle you need
> (or
>> get for that matter).
>
> S-N-O-R-E There is still a duty cycle, calculate it all you want..
> Measuring it is more accurate.
measure the wire...tell me what you see...
>
>> >
>> > I said that thermal runaway can occur at much less than the speaker's
>> > rated
>> > power under the proper conditions. George says it can't. He's wrong.
>>
>> Not really, you are saying that a device that can dissipate 30 watts will
>> burn up with 20 watts but not 40 watts. Sorry, sell that to arny.
>
> Show where I said that. I said device ratings change with the type of
> signal. They do.
The device rating changes? The device doesn't change... how does it change
its ratings? Is it a magic device? Why does the device decide to change
its ratings? How long does it take to decide to change its ratings? I hate
to tell you this, but after manufacture the device is what it is... until it
undergoes aging of the material or abuse. No device changes its ratings
based upon the music you listen to (the music would be a signal, you said
signal but in an audio world that usually corresponds to voice/music). What
signal do I apply to make a coil into a resistor?
You are lost.... I think you are a troll.....
>
>>
>> >
>> > Again. the culprit is power and time, and that in one situation the
> power
>> > is
>> > more continuous than the other.
>> RMS is the answer. In cases where peak power doesn't damage the device
>> (physically), your only claim is that it takes time to heat something up.
>> And, if you cool it down before it gets too hot you saved it. So, all
>> you
>> are claiming is that RMS power is the spec you should be using when doind
>> electrical design... is says the same thing....
>
> RMS power has cyles of power off and on Sax...
RMS is the Root Mean Square of the periodic waveform. Period, pure
definition.
>
>>
>> >
>> > Continuous power will make a speaker fail quicker than intermittent
> power,
>> > if only because the speakers are designed for intermittent power and
>> > not
>> > continuous.
>>
>> You design for continuous, because that is all there is. Anything else
>> is
>> useless specmanship.
>>
>
> You are confusing RMS with continuous signal. RMS ratings are usually
> measured with pink noise. Pink noise is not continuous.
>
>> I think you are confused about peak power (relatively uninteresting) and
>> RMS.
>
>
> Sax- you are incredibly confused on a number of issues. I never mentione
> peak power anywhere. YOU did.
I know that ... you said "power has cyles of power off and on" (this post
even). On would be the peak (high for you). I know that you can't
understand this.... try a light switch.... flip it one way and you have no
power, the other way gives you "PEAK LIGHT" or, using your highly technical
engineering term "on". You don't use the work PEAK, as I have started
before cuz you don't understand it. I use the term because it is proper
engineering terminology. You metioned peak power without useing the word
(for the 3rd time) because you are too stupid to relate teh concept (for the
third time). I never said you used the exact work PEAK and have already
explained it more than once that I recognize that you are too stupid to
understand it. I never expect you to use such a big word. I will not use
your poor wording. I just won't lower myself.
>
> All amp ratings I specified were the RMS ratings of the amps.
> Have a nice life.
At what duty cycle.... I hate to quote you but "There is still a duty
cycle". So, what duty cycle did you specify... cuz I didn't see it. I am
sure you will find an exact quote.... I just couldn't.
-I think it's time for the kill file for you. Stupid is as stupid does and
you does more of it for longer than anyone else in the news group (see, i
was able to find a positive for the use of age as proof of .... something)
-Sax
Personally, arny provides some comic entertainment, you provde nada. You
might have to pay him to get help on the book!
Saxology
<snip>
>
> Sax- you still are not reading. George is the one wanting a DC rating. I
> said it would be useless. Reread the entier thread. You are looking
> foolish.
> And most of it is not my doing.
George is correct. You have missed his viewpoint. He wants one as a
user... he wants the design to have some protection and he wants to know
what it is. Any speaker can be rated at DC. All he wants is... to know
what it is and have it guaranteed. He needs to know the rating of the
finished product, in a box, as shipped to him. George, from what I know of
his work, is a user of these devices, not a designer. He wants specs that
are guaranteed and prove the capability of the product, not some BS
marketing hype. Personally, I don't mind a little hype but the facts should
be available and they should be correct.
-Sax
Saxology
>
> "Saxology" <saxolo...@yahoo.com> wrote in message
> news:Hc8Bg.191$Qf....@newsread2.news.pas.earthlink.net...
>>
>> "liquidator" <liqui...@collide.org> wrote in message
>> news:44d4b61e$0$22530$8826...@free.teranews.com...
>> >
>> > Again DC is not clipping. Clipping certainly has a DC component, as
>> > does
> a
>> > sine wave.
>>
>> Unless you can't follow the conversation: wer are discussing the
> difference
>> between AC (no clip) performance and performance under a clipped signal.
>> And, for the record, there is no DC component to a sine wave, period, enf
> of
>> story. The average value of a sine wave is ZERO. There is no room for
>> DC
>> in the pro audio guy's world... we eliminate it.
>>
>
> Sax you lose. there is a DC component in a sine wave. And clipping is NOT
> DC!
The equation: S(t) = ASin(wt+p)
where is the DC component? A is amplitude, w is frequency, t is time, and p
is phase.
aint no DC term in there. A since wave IS AC .... DC is not AC. The FFT of
a sine wave will have one line at w. end of the class. school is out, you
old fool.
>
>
>> >
>> > Blocking caps have fallen out of favor. Do a search over at Pro Sound
> Web.
>> > There are good discussions there, no need to repeat them.
>>
>> I was using a simplified example.... try to follow along....
>>
> Nope. A simple example..
>
>>
>> Nice try, but no. The clipped waveform is the same
>
> As what? the compaison is between a clipped and non clipped amp. You can't
> read Sax.
>
>
> , the difference is that
>> the power amp can deliver the current to the load where in the case of
>> the
>> amp's limit being reached your RMS value increases but the amp has a hard
>> time delivering.... the reason the amp may overheat first.
>
> Close but no cigar. Sax you could not even pass a first year engineering
> test.
no proof there.... my fact is correct. you may not understand it (like most
things thus far). A clipped signal is a clipped signal.... regardless of
source of clipping the waveform can be the same.
Damn, you don't even have good responses. You should just move on.... you
are too old (your excuse, not mine) to understand.
-Sax
Earl Grey
>> "Earl Grey" <e...@t.pot> wrote in message news:44d46d4d$1...@clear.net.nz...
>>> That may be partially true if the amp is being fed by a tone source as
>>> opposed to musical input, but fourier analysis will tell you how much
>>> extra power is being added in harmonics when a musical waveform is
>>> clipped and its not really that significant. Its all above the
>> fundamental.
>>> However the loss of damping factor when an amp is clipping could have
>>> some nasty effects.
>> It is not harmonics. You obviously are not a trained engineer.
>>
>> In a representation of a wave, the hight indicates amlitude. The
> horizontal
>> indicates time.
>>
>> The amp hits it's power cieling and as long as the am is being driven to
>> full, STAYS THERE.
>>
>> The power stays at full longer. The speaker heats.
>>
>> Had you bothere to study you would have covered this in your first year.
>> The problem is neither you or George have ANY professional training. You
> are
>> either repating what someone told you, you read somewhere, or found on
>> Usenet. You got bad info, never verified it with a knowlegeable source.
> And
>> are now repeating it.
>>
>>
>
> Earl, let me apologise for the tone her. After reading it, it comes acroos
> much harsher than I intended.
>
> Hank posted elswhere, the written word often comes across harsher, since
> you lose the other person's body language and tone of voice.
>
> But please rad the entire thread,. AT NO POINT do I say it is harmonics
> that is the problem. that is a Usenet fallacy.
>
> The problem is a combination of the power and how long it stays on without a
> break. speakers are simply not designed for the power to stay on. operate a
> device outside it's design parameters and you get early failure THAT is all
> I am saying. Conversations with engineers at Beyma and Eminence conform what
> I have said in this thread. I am not making this up.
>
> From George's replies it's obvious he isn't reading everything. He has his
> mind made up and is defending it like a bulldog.
>
> It's so important to him to BE right that he has lost track of everything
> else.
>
>
>
Driving an amplifier into clipping does not create a DC component.
An amplifier which is below clipping is putting out less power than the
same amplifier driven into clipping.
When the level is increased into clipping, the peak level does not
increase, but the average level does, just the same as if the signal was
limited.
The heating effect in the transducer voice coil happens because of the
increase in average power irrespective of whether the peaks are clipped
or limited.
Earl Grey
> "Earl Grey" <e...@t.pot> wrote in message news:44d4737d$1...@clear.net.nz...>>> news:44d3769e$0$14075$8826...@free.teranews.com...>>>> news:cdLAg.9622$157....@newsread3.news.pas.earthlink.net...
>>>>>> Greg, I simply won't argue with you. 300 watts can blow a 600 watt
>>>>>> speaker.
>>>>>> If you had an engineering degree we would not be arguing. End of
> story,
>>>> I
>>>>>> am
>>>>>> done. It is all explained elsewhere in the thread.
>>>>>>
>>>>> only if the speaker is falsely rated, as is the industry wide
> practice<
>>>>> that is rated to sell speaker, not deliver accurate infomation about
> the
>>>>> speakers real ability to shed heat
>>>> George- you are just plain wrong. Why should a speaker be rated by it's
> DC
>>>> capability? NOBODY uses them that way!
>>>>
> It
>>>> never has and never will.
>>>> It is NOT widespread industry practice. It is the ONLY industry
> practice.
>>>> Manufacturers do their best to provide a "real life rating'"
>>> this is where we disagree
>>>
>>> To accuse
>>>> companies like JBL and Eminence, not to mention the rest of the entire
>>>> industry, of lying is just way off base.
>>> They are lying becuse everyone is lying
>>> if they didn't lie nobody would buy thier product
>>> I have a really good handle on what speaker can and can not do
>>> and its NOT based on marketing pitches
>>>> The problem with a real life rating is your real life is one reality,
>>>> mine
>>>> is another and there are billions more. There never will be a rating
> that
>>>> fits all situations.
>>>>
>>>> An honest manufacturer will provide a rating and point out how it was
>>>> arrived at. If you want you can probably figure the duty cycle of pink
>>>> noise
>>>> and figure out how to derate the speaker for how you are going to use
> it.
>>> EV USED to do that
>>>> An entire industry is not lying. You are asking for a rating that would
> be
>>>> meaningless to 99% of the people. I doubt you could stay in business
>>>> satisfying one percent of the people. It just ain't gonna happen. Might
> as
>>>> well quit bellyaching and move on.
>>> as I said one NEEDS to fabricate meaningless figures to sell product,
>>> because everyone else does
>>> THE FTC stepped in and forced HOME HIFI makes bto standardize power
> ratings
>>> of HOME HIFI amp
>>> why can this be done with PRO sound amps and speaker
>>> if we can't get REAL rateing at least get standardized rateings so
> useful
>>> comparisions can be made
>> The IEC and EIA ratings that speaker manufacturers now specify are from
>> tests with a 6dB crest factor noise source which is limited by clipping
>> applied for a certain time period after which the speaker should not
>> show any damage.
>> The guys that established the standards are the ones that have to use
>> OEM drivers tested to that standard in their products, so its not really
>> in their interests for the spec to be meaningless fabricated bullshit
>> Pink noise is the normal envelope that music fits within, so its a fair
>> test, it relates to normal system usage like a dynamometer test
>> relates to driving a car.
>
> We mostly agree here. I have been trying to communicate to George that ANY
> test is not real life usage, at best just gives you starting info,
>
> The standards you mention are actually far from standard. Many Pro gear
> manufacturers simply do not use them.
> So I have to completely disagree with the statement manufacturers specify
> those ratings. Many high quality manufacturers do not.
>
>
>
OEM speaker manufacturers like Beyma, B&C, 18sound, RCF, Precision
Devices, P Audio, Selenium, EV, Ciare, Eminence etc test their speakers
according to AES standards with a standard shaped pink noise signal for
the specified period of time, so that they can produce a specification
which means something to system integrators like EAW. Thats how they
know about the dissipation, the venting, the glue melting points etc Its
as standard as the bolt spacing and the TS parameters.
If the signal that you apply to those drivers is within that performance
envelope then they will dissipate the heat in the same way as they did
during the sample test.
There may very well be manufacturers who do this wrong or do this
dishonestly, then its up to us users to share the knowledge, but I'm
quite happy that the quality of driver specs is much improved over what
it was 20 years ago
Earl Grey
> "Earl Grey" <e...@t.pot> wrote in message news:44d46d4d$1...@clear.net.nz...
>> That may be partially true if the amp is being fed by a tone source as
>> opposed to musical input, but fourier analysis will tell you how much
>> extra power is being added in harmonics when a musical waveform is
>> clipped and its not really that significant. Its all above the
> fundamental.
>> However the loss of damping factor when an amp is clipping could have
>> some nasty effects.
>
> It is not harmonics. You obviously are not a trained engineer.
>
fuck you too
liquidator
"Earl Grey" <e...@t.pot> wrote in message news:44d560d2$1...@clear.net.nz...
> >
> Driving an amplifier into clipping does not create a DC component.
>
Where did I say it does? To the contrary I have posted several times to this
thread that clipping is not DC. Sax is the one who keeps insisting it is.
> An amplifier which is below clipping is putting out less power than the
> same amplifier driven into clipping.
> When the level is increased into clipping, the peak level does not
> increase, but the average level does, just the same as if the signal was
> limited.
What happens is, as the amp is clipped harder, it stays at full power
longer.
What I said was this-
Postulate there are 2 different amps. One is substantially larger.
Drive the small one to 100% clipping. Call it what you want. Average power
or duty cyle- the am is at 100% all the time. Until it thermals or dies.
The power is at a constant with very little interruptions.
Drive the second, larger, amp to the same level.
The power is higher at points, but low at others.
The difference is the power is not as constant. There are peaks and valleys.
Are we OK so far?
Same average power level, but differently applied. Speakers are not made to
handle constant power. They must be derated drastcally when operated that
way. It is possible for the smaller amp to fry the speaker and the big one
not do it. I never said it was 100%
What I said was it is possible for a 200 watt amp to blow a 600 watt
speaker. the 600 watt rating is most likely taken with Pink noise. It will
handle less with a 100% clipped signal.
George replied:
only if said 200 watt amp is putting out more than 600 watts when clipped
or if the speaker is not REALLY a 600 watt speaker
> The heating effect in the transducer voice coil happens because of the
> increase in average power irrespective of whether the peaks are clipped
> or limited.
Limiting can cause a similar effect. Clipping, if you want to look at it
that way, is a very severe limiting. Actually compression, since as you
drive the amp harder you are raising the floor. If you hit your limiters
really hard, you are getting close to the same effect as 100% clipping
assuming the limiter act as fast as the amp clips.. Are we arguing
semantics? Not sure here.
The point is, average power is not the only thing that needs considered. If
the power is constant, and applied at a rate faster than the speaker can
sink it, the speaker will fail.
The speaker may be able to sink the same average power that is not a
constant ( as in uncompressed, unlimited and unclipped), since that was it's
design application. Speakers are not designed to handle constant power.
Disregarding possibly sirens, which none of us use anyway..
As I said, I have discussed this with engineers from 2 different speaker
companies. They are the source for the info.
A number of companies I have not talked to, such as JBL and Peavey, have
warned not to underpower speakers.
Thanks for your patience, let me know what you think.
Saxology
>
> "Saxology" <saxolo...@yahoo.com> wrote in message
> news:NAaBg.36$Sn3...@newsread3.news.pas.earthlink.net...
>>
>> "liquidator" <liqui...@collide.org> wrote in message
>> news:44d50e28$0$22492$8826...@free.teranews.com...
>> ><snip>
>>
>>
>> I worked for Altec Lansing.
>>
>> Ah yes, had some of those speaks on my HiFi PC. Good work I'm sure.
>>
> You just showed you know absolutely nothing. not the same company.
http://www.alteclansing.com/product_cat_gaming.asp?region=northam
altec lansing is altec lansing.... game on ...
>
>
>>
>>. Smarter than you I have proved.
>
> You have proved nothing but zero knowledge and the ability to run your
> mouth.
Too bad you have no facts to prove your case.... I gave equations and
derivations... pure engineering. you have provided BS, repeated many times.
good luck with the book.... The chapter on how AC is DC shoulkd be
thrilling...
-Sax
Rupert
liquidator wrote:
> You are confusing RMS with continuous signal. RMS ratings are usually
> measured with pink noise. Pink noise is not continuous.
rms ratings are derived from sine wave test signals. Pink noise is used
for EIA ratings.
Rupert
Saxology
"liquidator"
<Snip>
>
> The difference is the power is not as constant. There are peaks and
> valleys.
>
> Are we OK so far?
No, you have never used the term "peak". You dare me to find where you
have. You have used it here but you have proven that you never used it...
but you used it here but claim you didn't use it... but you used it here...
idiot.
>
> Same average power level, but differently applied. Speakers are not made
> to
> handle constant power. They must be derated drastcally when operated that
> way. It is possible for the smaller amp to fry the speaker and the big one
> not do it. I never said it was 100%
>
> What I said was it is possible for a 200 watt amp to blow a 600 watt
> speaker. the 600 watt rating is most likely taken with Pink noise. It will
> handle less with a 100% clipped signal.
>
> George replied:
>
> only if said 200 watt amp is putting out more than 600 watts when clipped
> or if the speaker is not REALLY a 600 watt speaker
And George would be correct. If no specification is violated, the speaker
will be fine.
>
>
>
>> The heating effect in the transducer voice coil happens because of the
>> increase in average power irrespective of whether the peaks are clipped
>> or limited.
Power is instantaneous it is given by the equation P=Re[V(jw)*I(jw)#] where
# denotes the complex congugate of the current. It is because you do not
drive the device with DC in normal mode that you use RMS power to predict
time averaged power dissipation, and, therfore heat.
>
> Limiting can cause a similar effect. Clipping, if you want to look at it
> that way, is a very severe limiting. Actually compression, since as you
> drive the amp harder you are raising the floor. If you hit your limiters
> really hard, you are getting close to the same effect as 100% clipping
> assuming the limiter act as fast as the amp clips.. Are we arguing
> semantics? Not sure here.
>
>
> The point is, average power is not the only thing that needs considered.
> If
> the power is constant, and applied at a rate faster than the speaker can
> sink it, the speaker will fail.
If power is constant, it is constant. It doesn't get "applied at a faster
rate" or a slower rate. It is constant, per your statement... let me see if
I can find it... yup, there it is: "If the power is constant" How do you
vary the rate of power application in a constant power application?
Chapter 10 of your text should cover this. It is a fine point that only you
can shed light on.
>
> The speaker may be able to sink the same average power that is not a
> constant ( as in uncompressed, unlimited and unclipped), since that was
> it's
> design application. Speakers are not designed to handle constant power.
> Disregarding possibly sirens, which none of us use anyway..
>
> As I said, I have discussed this with engineers from 2 different speaker
> companies. They are the source for the info.
You claim to be the big altec lansing speaker designer with age to back it
up... you should know the answer without discussing it, it is obvious. You
really need some education.
>
> A number of companies I have not talked to, such as JBL and Peavey, have
> warned not to underpower speakers.
They sized you up properly.... you used a small amp with a duty cycler
attachment under constant power applied slower than usual and thought the
speakers were too soft? Did they tell ya to turn it up or to just get a
bigger amp capable of faster continuous power (with a big red LED on the
front panel to amuse ya)?
>
> Thanks for your patience, let me know what you think.
It's not patients... did ya take your little pink pill yet? I think when
you skip a dose you can take 2 to replenish your duty cycle!
-Sax
Saxology
"Earl Grey" <e...@t.pot> wrote in message news:44d56685$1...@clear.net.nz...
I think he is some kind of troll... makes up crap from jargon he has heard
at the drinking fountain. Prolly a message boy at a Bose distribution
facility.
-Sax
Rupert
liquidator wrote:
> Sax you lose. there is a DC component in a sine wave.
What is this dc component? There is a dc heating equivalent which is
what the rms rating of a driver is, but I'm not aware of a dc component
within the signal itself.
Rupert