Recommend a Replacement Speaker for JBL Control 12SR?

[Paul]

12" Woofer cone distorts badly, due to torn paper
cone:

http://www.jblpro.com/pub/obsolete/Control_12sr.pdf

I believe the tweeter is fine.

Can anyone recommend a replacement woofer?

I've never tried re-coning: Is it relatively successful
the first time? I am good with my hands.

Thanks for any good feedback.....

[david gourley]

Paul <quill...@gmail.com> said...news:o7a6hl$a4b$1...@dont-email.me:

You can find recone kits on eBay or SimplySpeakers.com. I got an edge kit
for some JBL 4408s and that turned out ok.

I would verify the type of voice coil before ordering to ensure a match.

david

---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus

[Scott Dorsey]

In article <o7a6hl$a4b$1...@dont-email.me>, Paul <quill...@gmail.com> wrote:
> 12" Woofer cone distorts badly, due to torn paper
>cone:
>
> http://www.jblpro.com/pub/obsolete/Control_12sr.pdf
>
> I believe the tweeter is fine.
>
> Can anyone recommend a replacement woofer?

You want an exact equivalent from JBL. You might be able to make something
else work by selecting parameters carefully, but you really don't want to do
that.

The Control 12 is not sufficiently precision equipment that I'd worry about
replacing just one woofer in the pair, though.

If it were me, I'd pull the old woofer and send it to Cardinal Sound and
Motion Picture in Baltimore and have them recone it. They are a JBL factory
repair shop and do good work.

> I've never tried re-coning: Is it relatively successful
>the first time? I am good with my hands.

Ten years ago I would have told you not to try it unless you had someone with
you who had done it to show you exactly what it should look like lined up,
but these days with a million Youtube videos out there, you might do well
enough just to watch a few of them and see what everything is supposed to
look like. It's not rocket science, but it's fairly precise work making sure
everything is shimmed up and moves straight.

The problem is getting the kit from JBL if you aren't an authorized dealer.
And I would suggest avoiding the third-party kits which are fine if you are
just replacing the surround but aren't going to be a perfect match for the
voice coil and spider.

If it were me, I'd ship it to Cardinal but if you want to do it yourself it's
a good thing to learn to do. And this is a comparatively easy driver to learn
on.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[geoff]

On 7/02/2017 7:42 AM, Scott Dorsey wrote:

> The problem is getting the kit from JBL if you aren't an authorized dealer.
> And I would suggest avoiding the third-party kits which are fine if you are
> just replacing the surround but aren't going to be a perfect match for the
> voice coil and spider.
>
> If it were me, I'd ship it to Cardinal but if you want to do it yourself it's
> a good thing to learn to do. And this is a comparatively easy driver to learn
> on.
> --scott
>

Generally a straightforward procedure, if you don't panic !

But doubt the idea of a generic re-cone kit, as there may well be
significant(?) differences in weight, stiffness, compliance, etc of
cone, surround, leadout, and spider material. And then there are the
voice-coil material/gauge/wire-shape/windings/fluid, former, etc.

So I'd say go with a genuine recone kit if you can get it, or if not
maybe recone both woofers with the same kit.

.... if you consider the speakers worth it.

Or pick up another used pair complete, then you'll still have a spare
for next time !

geoff

[mako...@yahoo.com]

>
> Or pick up another used pair complete, then you'll still have a spare
> for next time !
>

depending upon how bad the rips.... some well applied Elmer's glue could work?

m

[Scott Dorsey]

In article <3ab85623-c1b9-46ac...@googlegroups.com>,

I'd never recommend that on a precision device since it's going to change
the breakup behaviour considerably. But on a Control 12, I might try it
before investing any money.

[Paul]

On 2/6/2017 11:42 AM, Scott Dorsey wrote:
> In article <o7a6hl$a4b$1...@dont-email.me>, Paul <quill...@gmail.com> wrote:
>> 12" Woofer cone distorts badly, due to torn paper
>> cone:
>>
>> http://www.jblpro.com/pub/obsolete/Control_12sr.pdf
>>
>> I believe the tweeter is fine.
>>
>> Can anyone recommend a replacement woofer?
>
> You want an exact equivalent from JBL. You might be able to make something
> else work by selecting parameters carefully, but you really don't want to do
> that.
>
> The Control 12 is not sufficiently precision equipment that I'd worry about
> replacing just one woofer in the pair, though.
>
> If it were me, I'd pull the old woofer and send it to Cardinal Sound and
> Motion Picture in Baltimore and have them recone it. They are a JBL factory
> repair shop and do good work.

Ok, I'm going to use this speaker as a stand-alone unit: There is
no other speaker, so I don't need to match anything.

Let's say I wanted to just buy a speaker replacement: Can anyone
recommend a good one?

[Phil Allison]

Paul wrote:

>
>
> Ok, I'm going to use this speaker as a stand-alone unit: There is
> no other speaker, so I don't need to match anything.
>
> Let's say I wanted to just buy a speaker replacement: Can anyone
> recommend a good one?
>

** The JBL 2206H would be a good one, the magnet is bigger so make sure there is room for it .

http://www.parts-express.com/jbl-2206h-12-high-power-lf-driver--294-480


.... Phil

..... Phil

[Scott Dorsey]

In article <o7b28v$mrs$1...@dont-email.me>, Paul <quill...@gmail.com> wrote:
>>
>> If it were me, I'd pull the old woofer and send it to Cardinal Sound and
>> Motion Picture in Baltimore and have them recone it. They are a JBL factory
>> repair shop and do good work.
>
> Ok, I'm going to use this speaker as a stand-alone unit: There is
>no other speaker, so I don't need to match anything.
>
> Let's say I wanted to just buy a speaker replacement: Can anyone
>recommend a good one?

Not without knowing the T-S parameters of the original driver and even then
you will take some fiddling around to make sure it matches well. If you pull
the working driver and measure Fs and Vas and estimate Xmax by eye you can
likely get fairly close.

But really, I wouldn't do this. Because you'll find you wind up spending a
lot more money than you would just getting the replacement from JBL. It
won't be that expensive.

[Paul]

Whoa! 600 Watts continuous!

I only need 200 Watts!

[Mike Rivers]

On 2/6/2017 7:50 PM, Paul wrote:
> Whoa! 600 Watts continuous!
>
> I only need 200 Watts!

Then you won't blow it up.



--

For a good time, call http://mikeriversaudio.wordpress.com

[Scott Dorsey]

Speaker power ratings are pretty random, and are actually the least important
of all the numbers that you care about.

[Paul]

What kind of a retarded statement is that?

Ok, I'll just put a 50 Watt speaker into it, and then drive it
with 200 Watts RMS continuous!

NOT A GOOD IDEA!

[Paul]

On 2/6/2017 6:31 PM, Mike Rivers wrote:
> On 2/6/2017 7:50 PM, Paul wrote:
>> Whoa! 600 Watts continuous!
>>
>> I only need 200 Watts!
>
> Then you won't blow it up.
>

True, but I don't want to over-engineer it!

:/

[Phil Allison]

**The original speaker used a 3 inch voice coil and smaller magnet while the 2206H uses a 4 inch voice coil and larger magnet - hence the extra power rating.

Otherwise they are nearly identical as both have JBL's "Vented Gap Cooling" which really works.



.... Phil

[Mike Rivers]

On 2/6/2017 11:58 PM, Paul wrote:
> Ok, I'll just put a 50 Watt speaker into it, and then drive it
> with 200 Watts RMS continuous!
>
> NOT A GOOD IDEA!

No, it isn't a good idea, but then why would you do that other than to
see if you can blow the speaker? A loudspeaker's power rating is more a
limit than a requirement. Sensitivity is what describes how loud it will
be for a given input power. If you're going to use published
specifications as your guide to choosing a component (and indeed there
are good reasons to do that, sometimes, for some components), you should
understand what those specifications actually mean.

You wouldn't want to use an electrolytic capacitor rated at 250 volts in
a circuit where it never sees more than 2 volts across it, because it
may not be close to its specified value that far away from its rated
working voltage. Nor would you put a 25 volt capacitor in a circuit
where it sees 250 volts - but there's a different reason for that.

Remember, too, that the difference between 400 watts and 200 watts is
only 3 dB.

[Paul]

On 2/7/2017 4:50 AM, Mike Rivers wrote:
> On 2/6/2017 11:58 PM, Paul wrote:
>> Ok, I'll just put a 50 Watt speaker into it, and then drive it
>> with 200 Watts RMS continuous!
>>
>> NOT A GOOD IDEA!
>
> No, it isn't a good idea, but then why would you do that other than to
> see if you can blow the speaker? A loudspeaker's power rating is more a
> limit than a requirement. Sensitivity is what describes how loud it will
> be for a given input power. If you're going to use published
> specifications as your guide to choosing a component (and indeed there
> are good reasons to do that, sometimes, for some components), you should
> understand what those specifications actually mean.
>
> You wouldn't want to use an electrolytic capacitor rated at 250 volts in
> a circuit where it never sees more than 2 volts across it, because it
> may not be close to its specified value that far away from its rated
> working voltage. Nor would you put a 25 volt capacitor in a circuit
> where it sees 250 volts - but there's a different reason for that.
>

There shouldn't be a problem using a 250V rated cap in that
situation, but you would have way over-engineered it!

Only a retard wouldn't consider the wattage rating of a
speaker!

> Remember, too, that the difference between 400 watts and 200 watts is
> only 3 dB.
>

That's obvious, but try driving a 200 Watt rated speaker with
400 Watts, and see what happens!

DUUUUUHH!!

[Mike Rivers]

> On 2/7/2017 4:50 AM, Mike Rivers wrote:
>> On 2/6/2017 11:58 PM, Paul wrote:

>> You wouldn't want to use an electrolytic capacitor rated at 250 volts in
>> a circuit where it never sees more than 2 volts across it, because it
>> may not be close to its specified value

On 2/7/2017 12:17 PM, Paul wrote:
> There shouldn't be a problem using a 250V rated cap in that
> situation, but you would have way over-engineered it!

I just explained why there could be a problem using a capacitor with a
working voltage that's well over the actual working voltage in the
circuit. Electrolytic capacitors are rated for _working_ voltage, not
destruction voltage. If a 10 uF 250 v capacitor is only 1 uF because
it's seeing only 10% of its working voltage (that's not a formula, by
the was, just an "if") then it's not doing what it's supposed to do, and
that could be a problem.

> Only a retard wouldn't consider the wattage rating of a
> speaker!

No. Only someone ignorant of how loudspeakers are rated would interpret
it as the maximum power rating of the amplifier that's driving it. A
poorly built and stupidly rated speaker (both cases are not uncommon)
driven by a 50 watt amplifier that's clipping badly is more likely to
suffer damage than when driven by a 500 watt amplifier that's
undistorted when running 100 watts.

A lower powered amplifier doesn't necessarily protect a loudspeaker -
but a properly rated fuse might.

>> Remember, too, that the difference between 400 watts and 200 watts is
>> only 3 dB.

> That's obvious, but try driving a 200 Watt rated speaker with
> 400 Watts, and see what happens!

A 400 watt amplifier doesn't always put out 400 watts. Only a retard
would turn it up until the speaker failed. But some do anyway.

[Scott Dorsey]

In article <o7bk3b$se7$1...@dont-email.me>, Paul <quill...@gmail.com> wrote:
>>
>> Speaker power ratings are pretty random, and are actually the least important
>> of all the numbers that you care about.
>
> What kind of a retarded statement is that?
>
> Ok, I'll just put a 50 Watt speaker into it, and then drive it
>with 200 Watts RMS continuous!

Might be perfectly fine. Might not be.

The speaker power ratings make a lot of assumptions about the waveform they
are being sent, and involve a whole lot of handwaving. They often owe more to
the marketing department than any actual engineering.

Remember that the difference between 50 watts and 200 watts is only 6dB.

[geoff]

On 8/02/2017 6:17 AM, Paul wrote:

>
> Only a retard wouldn't consider the wattage rating of a speaker!
>

Call me a retard then. Have been running one set of speakers rated at a
mere 50W on a 200W amp for years without a problem.

Wouldn't recommend that for everyone in every situation though ....

geoff

[JackA]

That's an efficient speaker, but sure to match woofer characteristics or replace both woofers.

Jack

[Neil]

On 2/7/2017 12:47 PM, Scott Dorsey wrote:
>
> Remember that the difference between 50 watts and 200 watts is only 6dB.
> --scott
>

Hmm. I would think that the dB difference would depend on the efficiency
performance of the driver, not just the input wattage. One challenge
when matching drivers is picking those that have the same input power to
dB characteristics over the rated range.

Then again, I'm admittedly "old school", and maybe modern drivers are
much better matched than they used to be.

--
best regards,

Neil

[Scott Dorsey]

In article <o7d83o$lcu$1...@dont-email.me>, Neil <ne...@myplaceofwork.com> wrote:
>On 2/7/2017 12:47 PM, Scott Dorsey wrote:
>>
>> Remember that the difference between 50 watts and 200 watts is only 6dB.
>>

>Hmm. I would think that the dB difference would depend on the efficiency
>performance of the driver, not just the input wattage. One challenge
>when matching drivers is picking those that have the same input power to
>dB characteristics over the rated range.

That would be output power, not input power.

Input power is just a function of voltage and load impedance.

Which, incidentally, is one of the reasons why 'rated power' is such a
doubtful number, that the load impedance varies so much on the speaker.
You'll see some woofer systems that drop down to 3 ohms at one frequency
than rise up to 50 ohms at some other frequency.

But.... even so.... if the speaker is linear, if you add 6dB input power
you'll get another 6dB output power.

[Neil]

What I was saying is basically the same thing; a speaker receiving xW (I
called it "input wattage", which may not be modern jargon) will put out
YdB. The "efficiency performance" addresses your point about
frequency-dependent impedance variations and includes physical qualities
of the driver that affect variable frequency linearity (IOW, a driver
that may have linear I/O power at a single frequency may not have a
linear variable frequency response).

I agree that 'rated power' is a very general reference.

The enclosure adds a barrel full of other variables, which is why I
wonder what the OP is really going to wind up with. I'd be hesitant to
spend $450 to find out. ;-)

--
best regards,

Neil

[Paul]

On 2/7/2017 10:33 AM, Mike Rivers wrote:
>
>> On 2/7/2017 4:50 AM, Mike Rivers wrote:
>>> On 2/6/2017 11:58 PM, Paul wrote:
>
>>> You wouldn't want to use an electrolytic capacitor rated at 250 volts in
>>> a circuit where it never sees more than 2 volts across it, because it
>>> may not be close to its specified value
>
> On 2/7/2017 12:17 PM, Paul wrote:
>> There shouldn't be a problem using a 250V rated cap in that
>> situation, but you would have way over-engineered it!
>
> I just explained why there could be a problem using a capacitor with a
> working voltage that's well over the actual working voltage in the
> circuit. Electrolytic capacitors are rated for _working_ voltage, not
> destruction voltage. If a 10 uF 250 v capacitor is only 1 uF because
> it's seeing only 10% of its working voltage (that's not a formula, by
> the was, just an "if") then it's not doing what it's supposed to do, and
> that could be a problem.
>

The capacitance value is also dependent on ESR and parasitic
inductances, so it's frequency and temperature dependent too:


http://www.kemet.com/Lists/TechnicalArticles/Attachments/191/Why%2047%20uF%20capacitor%20drops%20to%2037%20uF-%2030%20uF-%20or%20lower.pdf

And from
http://electronics.stackexchange.com/questions/190362/electrolytic-capacitor-voltage-rating-vs-capacitance/195211

"Long story short, you can replace an electrolytic cap with another one
of the same value but higher voltage rating.

Electrolytic capacitors usually have a very lose tolerance to begin
with, and with age and heat their capacitance drops a lot. They also
change their characteristics with applied DC voltage, but this effect is
a less drastic as in multi-layer ceramic types.

Given that you can't really trust the exact capacitance longer than a
few weeks, it is very unlikely that someone designs in an electrolytic
capacitor and expects the value to be exact. That's why you will often
find them in non critical situations where a capacitor of some ballpark
capacitance is needed but the exact value does not matter much.

Such applications are buffer capacitors and smoothing capacitors in
power supplies. In cheap audio devices you'll sometimes find them as DC
blocking capacitors as well.

In all of these cases the performance of the device will not change much
if the real capacitance changes by ... lets say ... 50 percent. So a
change to a different voltage-rated part won't hurt.

Using capacitors with a higher voltage rating as strictly required is
btw a good thing because the capacitor will not age as quickly as one
working on it's limit."


But yours is a bullshit argument anyways: There would be no
problem driving a 250 Watt speaker with 2 Watts, unless the rating
was insanely off!

>> Only a retard wouldn't consider the wattage rating of a
>> speaker!
>
> No. Only someone ignorant of how loudspeakers are rated would interpret
> it as the maximum power rating of the amplifier that's driving it. A
> poorly built and stupidly rated speaker (both cases are not uncommon)
> driven by a 50 watt amplifier that's clipping badly is more likely to
> suffer damage than when driven by a 500 watt amplifier that's
> undistorted when running 100 watts.
>
> A lower powered amplifier doesn't necessarily protect a loudspeaker -
> but a properly rated fuse might.
>
>>> Remember, too, that the difference between 400 watts and 200 watts is
>>> only 3 dB.
>
>> That's obvious, but try driving a 200 Watt rated speaker with
>> 400 Watts, and see what happens!
>
> A 400 watt amplifier doesn't always put out 400 watts. Only a retard
> would turn it up until the speaker failed. But some do anyway.
>

I never said it did. Only a retard would rather use a lower
Wattage rated speaker than the driving amplifier, because even if the
ratings are inexact, you'd still have a better chance of not blowing
the speaker if you match a 400 Watt speaker to a 400 Watt system!

[None]

"Neil" <ne...@myplaceofwork.com> wrote in message
news:o7djsl$3lt$1...@dont-email.me...

>>>> Remember that the difference between 50 watts and 200 watts is
>>>> only 6dB.
>>>>
>>> Hmm. I would think that the dB difference would depend on the
>>> efficiency
>>> performance of the driver, not just the input wattage.

The ratio of 50 W and 200 W is difference of 6 dB, regardless of the
efficiency.

[Paul]

Certainly Figure 4 on this site is a severe over-simplification:


http://www.st.com/content/ccc/resource/technical/document/application_note/60/f9/45/6d/c1/02/40/8c/CD00298262.pdf/files/CD00298262.pdf/jcr:content/translations/en.CD00298262.pdf

So how do the speaker company engineers decide on the rating for
their speakers?

If they made some reasonable guesses as to the temperature where
the voice coil insulation and glues start to break down, they could get
an idea of the power rating.

Perhaps the only accurate way is to get a few examples and perform
destructive testing with various sounds though them, at various RMS
Wattages, with the understanding that a constant 1kHz sine wave will NOT
be the same test as a good variety of REAL music.

They could then establish a Mean Time before Failure (MTBF), and
say statistically that you could use this speaker with this amp, and
expect an average of this many hours of usage before blowing the speaker.

But they can't completely pull a number out of their asses!

Or do they? Haha!

:)

[Scott Dorsey]

In article <o7djsl$3lt$1...@dont-email.me>, Neil <ne...@myplaceofwork.com> wrote:
>>
>What I was saying is basically the same thing; a speaker receiving xW (I
>called it "input wattage", which may not be modern jargon) will put out
>YdB.

No. A speaker receiving X watts or X dBW puts out Y dBSPL.

The decibel is a ratio, it is not a measurement. In order for a decibel
to be meaningful you have to put a reference point on it.

We measure watts, sound pressure, and voltage all using decibel ratios.

>The "efficiency performance" addresses your point about
>frequency-dependent impedance variations and includes physical qualities
>of the driver that affect variable frequency linearity (IOW, a driver
>that may have linear I/O power at a single frequency may not have a
>linear variable frequency response).

This is true. However, I was talking about input power in watts. 10 watts
is 10dB higher than one watt. This has nothing necessarily to do with the
output level in dBSPL (decibels with respect to reference sound pressure level
in air).

>The enclosure adds a barrel full of other variables, which is why I
>wonder what the OP is really going to wind up with. I'd be hesitant to
>spend $450 to find out. ;-)

Indeed, especially when getting the existing driver rebuilt is comparatively
inexpensive and easy.

[Scott Dorsey]

In article <o7dlbn$81e$1...@dont-email.me>, Paul <quill...@gmail.com> wrote:
>
> But yours is a bullshit argument anyways: There would be no
>problem driving a 250 Watt speaker with 2 Watts, unless the rating
>was insanely off!

I suggest trying it, although of course not knowing the speaker efficiency
it's hard to know. Efficiency is an actual measurement that is of some
value, as opposed to a marketing number like power ratings.

Many speakers have a minimum power rating on them, again because people in
the marketing department are afraid of people damaging them by clipping
an undersized amplifier. That rating is about as fake as the maximum
power rating too.

[PStamler]

Electro-Voice used to use a waveform for testing speakers which they claimed approximated the spectral and dynamic characteristics of a clipped electric guitar signal. Haven't heard about that for a while.

Peace,
Paul S.

[Paul]

So if your argument is to ignore speaker power ratings, and
always use speakers that are like 6 dB less than the driving amplifier,
and never use speakers rated HIGHER than the amp, then that's a losing
argument!

The ratings can't be completely fake....they must do at least some
destructive testing on sample units.

[Scott Dorsey]

In article <o7dp86$ibq$1...@dont-email.me>, Paul <quill...@gmail.com> wrote:
>
> So if your argument is to ignore speaker power ratings, and
>always use speakers that are like 6 dB less than the driving amplifier,
>and never use speakers rated HIGHER than the amp, then that's a losing
>argument!

No, my arguments are that the speaker ratings have to be taken with a serious
grain of salt, that you are much better off using the efficiency and maximum
SPL envelope to size systems than an estimated rating, and that the most
important key to preventing speaker damage is to use your ears and back off
when the drivers become nonlinear.

> The ratings can't be completely fake....they must do at least some
>destructive testing on sample units.

For complete cabinets you can do that, and there are test waveforms that
you can use. For a raw driver you can't do that because the total excursion
of the driver depends on the cabinet; a driver that can handle one power
level in one cabinet may have totally different power handling in another.

[Trevor]

On 8/02/2017 11:44 AM, Scott Dorsey wrote:
> In article <o7dp86$ibq$1...@dont-email.me>, Paul <quill...@gmail.com> wrote:
>> The ratings can't be completely fake....they must do at least some
>> destructive testing on sample units.

There is no MUST. Reputable manufacturers do, many others do not.

> For complete cabinets you can do that, and there are test waveforms that
> you can use. For a raw driver you can't do that because the total excursion
> of the driver depends on the cabinet; a driver that can handle one power
> level in one cabinet may have totally different power handling in another.

Not necessarily true. For a tweeter the cabinet is irrelevant. For a
woofer tested at 1kHz as some do, or even 400+ Hz as some others do, the
cabinet is mostly irrelevant, other than the fact it will probably
restrict air flow to the voice coil and magnet assembly and thus reduce
the power rating.

Trevor.

[geoff]

On 8/02/2017 12:32 p.m., Paul wrote:
>
>
> Such applications are buffer capacitors and smoothing capacitors in
> power supplies. In cheap audio devices you'll sometimes find them as
> DC blocking capacitors as well.

Only in 'cheap' ?!!!

geoff

[Mike Rivers]

On 2/7/2017 7:39 PM, Paul wrote:

> So if your argument is to ignore speaker power ratings, and
> always use speakers that are like 6 dB less than the driving amplifier,
> and never use speakers rated HIGHER than the amp, then that's a losing
> argument!

That's two arguments. Or maybe three. I think you're looking for a rule,
when there is none. Experience and common sense are the bywords here.
You're not going to blow up a speaker unless you do something stupid.
And if you don't do something stupid, you can use any amplifier that you
want as long as you can get the volume you need without it being distorted.

In normal operation you'' hear distortion before you do any damage, and
if you continue to let it distort, whether it's the amplifier clipping
or the speaker being driven against the stops or overheating, then
you're doing something stupid. And if you let the system feed back at
full power, or plug something in that causes hum at full power, that's
something stupid, too. Most speakers will survive that for a short
period of time, and if you don't make it stop, that's stupid.

> The ratings can't be completely fake....they must do at least some
> destructive testing on sample units.

They know how much current it takes for how long before the voice coil
will melt open, but there are enough different ways that you can destroy
a speaker mechanically that it's really hard to relate them to amplifier
power.

[Paul]

On 2/7/2017 6:56 PM, Mike Rivers wrote:
> On 2/7/2017 7:39 PM, Paul wrote:
>
>> So if your argument is to ignore speaker power ratings, and
>> always use speakers that are like 6 dB less than the driving amplifier,
>> and never use speakers rated HIGHER than the amp, then that's a losing
>> argument!
>
> That's two arguments. Or maybe three. I think you're looking for a rule,
> when there is none. Experience and common sense are the bywords here.
> You're not going to blow up a speaker unless you do something stupid.
> And if you don't do something stupid, you can use any amplifier that you
> want as long as you can get the volume you need without it being distorted.
>
> In normal operation you'' hear distortion before you do any damage, and
> if you continue to let it distort, whether it's the amplifier clipping
> or the speaker being driven against the stops or overheating, then
> you're doing something stupid. And if you let the system feed back at
> full power, or plug something in that causes hum at full power, that's
> something stupid, too. Most speakers will survive that for a short
> period of time, and if you don't make it stop, that's stupid.
>

You aren't doing a good job of convincing me there isn't any
difference in the design of a 600W speaker and a 50 Watt one....

>> The ratings can't be completely fake....they must do at least some
>> destructive testing on sample units.
>
> They know how much current it takes for how long before the voice coil
> will melt open, but there are enough different ways that you can destroy
> a speaker mechanically that it's really hard to relate them to amplifier
> power.
>

If companies made some reasonable guesses as to the temperature

where the voice coil insulation and glues start to break down, they

could get an idea of the power rating. The AWG, or thickness of the
coil wire will make a difference too.

[Phil Allison]

Mike Rivers wrote:

>
>
> No. Only someone ignorant of how loudspeakers are rated would interpret
> it as the maximum power rating of the amplifier that's driving it.
>

** But that is often how speaker makers come up with their inflated numbers.

Its the amp power ( usually rms sine wave) that they figure is OK with the speaker under normal programme conditions with little or no clipping. The average power being delivered is then at most 1/4 ( -6dB )of the amp's rated power.

At lot hen depends on what the speaker's intended use, ie home hi-fi, live sound, disco or guitar.

> poorly built and stupidly rated speaker (both cases are not uncommon)
> driven by a 50 watt amplifier that's clipping badly is more likely to
> suffer damage than when driven by a 500 watt amplifier that's
> undistorted when running 100 watts.
>

** Well, a 50watt sine wave rated amp will deliver at most 100W when heavily clipped - so matching the output of the 500watt model unclipped.

The idea of using a LARGER amp to solve speaker burn out problems is a complete nonsense.

Section 3.2 of my article on speaker failures makes the case pretty clear.

http://sound.whsites.net/articles/speaker-failure.html


.... Phil

[Phil Allison]

Paul wrote:

>
>
> "Long story short, you can replace an electrolytic cap with another one
> of the same value but higher voltage rating.
>
> Electrolytic capacitors usually have a very lose tolerance to begin
> with, and with age and heat their capacitance drops a lot.
>

** That is just not true.

New electros have a tolerance of +/-20% on capacitance and this value does not change significantly with age throughout the useful like of the part.

As the cap nears the end of its life ( because the electrolyte has nearly all evaporated) ESR rises but the capacitance stays.

The reason for this odd behaviour is simple, makers put about 5 times more electrolyte inside a given electro than it needs to work - so a large percentage has to disappear before it affects performance.

Shame how NONE of this info is in your links.

> They also
> change their characteristics with applied DC voltage, but this effect is
> a less drastic as in multi-layer ceramic types.
>

** It is never an issue, because electro are not used where capacitance value is critical - we have polystyrene film and NPO ceramic caps for that.

> Given that you can't really trust the exact capacitance longer than a
> few weeks,
>

** You plucked that out your arse ....

> it is very unlikely that someone designs in an electrolytic
> capacitor and expects the value to be exact.

** Correct.

> That's why you will often
> find them in non critical situations where a capacitor of some ballpark
> capacitance is needed but the exact value does not matter much.
>

** The common requirement of an electro these days is to have low self impedance at its operating frequency - which might be 50 to 100kHz. Here, the ESR value is king and the capacitance incidental.

> Such applications are buffer capacitors and smoothing capacitors in
> power supplies. In cheap audio devices you'll sometimes find them as DC
> blocking capacitors as well.
>

** Electros are normally used for that job, even in the most up market products -cos they do the job just perfectly. Audiophools may not agree, but they never agree on anything.



.... Phil

[Neil]

On 2/7/2017 7:24 PM, Scott Dorsey wrote:
> In article <o7djsl$3lt$1...@dont-email.me>, Neil <ne...@myplaceofwork.com> wrote:
>>>
>> What I was saying is basically the same thing; a speaker receiving xW (I
>> called it "input wattage", which may not be modern jargon) will put out
>> YdB.
>
> No. A speaker receiving X watts or X dBW puts out Y dBSPL.
>
> The decibel is a ratio, it is not a measurement. In order for a decibel
> to be meaningful you have to put a reference point on it.
>

Got it. My "old school jargon" presumes SPL when referring to dB in the
context of a driver, but I understand the difference. ;-)


--
best regards,

Neil

[Scott Dorsey]

In article <o7e0jf$41d$1...@dont-email.me>, Paul <quill...@gmail.com> wrote:
>
> If companies made some reasonable guesses as to the temperature
>where the voice coil insulation and glues start to break down, they
>could get an idea of the power rating. The AWG, or thickness of the
>coil wire will make a difference too.

Okay, there are two kinds of failures. The first is due to overheating, and
the second due to overexcursion.

In the case of woofers, you can predict overheating although it's very
interesting to watch because the speakers tend to use airflow through the
voice coil to cool it. So you can get into a situation where a high power
at a low frequency is fine because there's enough excursion and enough air
moving through, but a lower power at a higher frequency isn't.

Overexcursion issues are totally different, though, and the waveforms that
cause them are totally different. Which is really why there's so much
slop in all of these, that musical waveforms vary so much between types of
music.

> Perhaps the only accurate way is to get a few examples and perform
>destructive testing with various sounds though them, at various RMS
>Wattages, with the understanding that a constant 1kHz sine wave will NOT
>be the same test as a good variety of REAL music.

That's what folks do, and then they put a big safety margin into place before
they publish it. How big a safety margin? You'll have to ask the marketing
department.

> They could then establish a Mean Time before Failure (MTBF), and
>say statistically that you could use this speaker with this amp, and
>expect an average of this many hours of usage before blowing the speaker.

The only person who has ever even made a stab at that sort of thing is
Wolfgang Klippel. Klippel has done more to establish statistical quality
control of speaker drivers than anyone else ever, I suspect.

[Paul]

From your link: "Nominal Impedance = R plus 15% - where R is the
DC resistance in ohms

The "nominal impedance" of a woofer or instrument speaker is the
LOWEST value of the REAL impedance that driver exhibits in the audio
range and at room temperature. The actual minimum typically occurs in
the band between 200 Hz and 500 Hz and the usual test frequencies are
250 Hz or 400 Hz.

Being an impedance minimum means that it is a pure resistance too, with
current and voltage in phase. The extra 15% comes from energy losses in
the suspension, eddy currents the iron magnet structure and radiated sound."

So this estimated nominal impedance ignores the inductive
reactance of the voice coil, because it assumes lower testing
frequencies, where XL=2pifL will be low, and can be ignored?

Also from your link: "A "nominal watt" is based purely on a
simple, but absurd, calculation that assumes the speaker maintains it
nominal impedance at all frequencies and under all operating conditions.

The usual power handling test done on a high powered woofer is to
install it in a large cabinet or perhaps in free air, and feed it with
modified pink noise filtered to the 50 Hz to 500 Hz band or possibly the
50 Hz to 5,000 Hz band. (See note below.)

The output level from the amp is then adjusted upwards until the voice
coil is dangerously hot and left like that for a couple of hours. The
RMS voltage being delivered by the amp is measured, the value squared
and divided by the nominal impedance to give "max watts". See AES-2 1984
"Speaker Testing" link 2.

As a result of this patent absurdity - the actual watts dissipated by
the speaker during such testing may well be only 20 to 25% of the
published max watts figure."


I assume trying to calculate Power from Voltage x Current by
putting a current sensing resistor of 0.1 Ohm in series with the
speaker under test, would affect the measurements too much?

How hot is a "dangerously hot" voice coil? :)

Seems to me the best thing to do would be to measure
the RMS voltages, while incrementally increasing the pink noise output
level from the amplifier, until the speakers blows. Then you
could use the last measured RMS voltage (when the speaker still
survived) in the calculation.

[Paul]

Assuming speaker power ratings shouldn't be taken seriously:

How about if I took a Celestion G12P-80 speaker that I took out
of a broken Line 6 guitar amplifier, and slapped it into this JBL
Control 12SR?

That would be a rated 80 Watt speaker in a cab that is rated for
200 Watts. I assume the average guitar amp speaker has a different
frequency response curve than your average PA speaker?

I could be REAL careful about not over-driving it!

:)

[Scott Dorsey]

In article <o7ffhu$a2d$1...@dont-email.me>, Paul <quill...@gmail.com> wrote:
>
> How hot is a "dangerously hot" voice coil? :)

That depends entirely on the glue used and whether the voice coil is copper
or aluminum. In general the things done to improve power handling also
increase moving mass. But voice coil heating effects and how much you can
get away with ARE very well-studied.

> Seems to me the best thing to do would be to measure
>the RMS voltages, while incrementally increasing the pink noise output
>level from the amplifier, until the speakers blows. Then you
>could use the last measured RMS voltage (when the speaker still
>survived) in the calculation.

The problem is that speakers will fail much more easily by heating from a
pink noise source than from music. However, they will fail much more easily
from overexcursion from music than from a pink noise source.

So the ability to handle pink noise tells you little about the ability to
handle musical waveforms.

[Scott Dorsey]

In article <o7fg2u$ca5$1...@dont-email.me>, Paul <quill...@gmail.com> wrote:
>
> Assuming speaker power ratings shouldn't be taken seriously:
>
> How about if I took a Celestion G12P-80 speaker that I took out
>of a broken Line 6 guitar amplifier, and slapped it into this JBL
>Control 12SR?

Then it would sound totally different. Because the resonant frequency of
the driver is different, the efficiency of the driver is different, the
Q of the driver resonance is different, and the driver compliance is different.

The power rating? Nobody cares about that, that's pretty much irrelevant.

> That would be a rated 80 Watt speaker in a cab that is rated for
>200 Watts. I assume the average guitar amp speaker has a different
>frequency response curve than your average PA speaker?

THAT is an understatement. Also, you'll notice that the rating on that
Celestion bears no connection to that of a driver intended for PA applications
since the Celestion is intended to handle high duty cycle clipped waveforms.
It likely has better power handling than a 200 watt PA driver. But really,
power handling is the least of your worries.

[PStamler]

To the original poster: While the argument sbout rating goes on, save yourself some money. Instead of trying to revive that JBL, take the cash and go out and buy yourself a pair of Adam monitors, and enjoy.

Peace,
The Other Paul

[Paul]

I would be using this cab mainly for vocals.....maybe I should
just drop it in, and see what happens?

I don't have to glue the front grill on until I am happy
with the sound of it!

:)

[Mike Rivers]

On 2/8/2017 5:10 PM, Paul wrote:
> I would be using this cab mainly for vocals.....maybe I should
> just drop it in, and see what happens?

By Jove! I think he's got it!

[Paul]

On 2/8/2017 3:39 PM, Mike Rivers wrote:
> On 2/8/2017 5:10 PM, Paul wrote:
>> I would be using this cab mainly for vocals.....maybe I should
>> just drop it in, and see what happens?
>
> By Jove! I think he's got it!
>

I wasn't talking to you, dumbshit....

[Scott Dorsey]

In article <o7g4th$tke$1...@dont-email.me>, Paul <quill...@gmail.com> wrote:
>
> I would be using this cab mainly for vocals.....maybe I should
>just drop it in, and see what happens?

I told you what would happen: it won't be anything approaching flat. You'd
probably do better just to patch the existing one with white glue.

But you won't hurt anything by trying it, it just won't sound very good.

[Mike Rivers]

On 2/8/2017 5:54 PM, Paul wrote:
> I wasn't talking to you, dumbshit....

And I wasn't talking to you, I was making a pronouncement to the world.
You just happened to be there and had your eyes turned on. Try turning
on your ears, though, when you install the new speaker.

[Phil Allison]

Paul wrote:

Phil Allison wrote:
>
> >
> > Section 3.2 of my article on speaker failures makes the case pretty clear.
> >
> > http://sound.whsites.net/articles/speaker-failure.html
> >
>
>
> From your link: "Nominal Impedance = R plus 15% - where R is the
> DC resistance in ohms
>
> The "nominal impedance" of a woofer or instrument speaker is the
> LOWEST value of the REAL impedance that driver exhibits in the audio
> range and at room temperature. The actual minimum typically occurs in
> the band between 200 Hz and 500 Hz and the usual test frequencies are
> 250 Hz or 400 Hz.
>
> Being an impedance minimum means that it is a pure resistance too, with
> current and voltage in phase. The extra 15% comes from energy losses in
> the suspension, eddy currents the iron magnet structure and radiated sound."
>
>
> So this estimated nominal impedance ignores the inductive
> reactance of the voice coil, because it assumes lower testing
> frequencies, where XL=2pifL will be low, and can be ignored?
>

** Nope - it ignores nothing.

Read what you just quoted, the MINIMUM lies between two rises in impedance at low and high frequencies. How else could it be a minimum ?

>
> Also from your link: "A "nominal watt" is based purely on a
> simple, but absurd, calculation that assumes the speaker maintains it
> nominal impedance at all frequencies and under all operating conditions.
>
> The usual power handling test done on a high powered woofer is to
> install it in a large cabinet or perhaps in free air, and feed it with
> modified pink noise filtered to the 50 Hz to 500 Hz band or possibly the
> 50 Hz to 5,000 Hz band. (See note below.)
>
> The output level from the amp is then adjusted upwards until the voice
> coil is dangerously hot and left like that for a couple of hours. The
> RMS voltage being delivered by the amp is measured, the value squared
> and divided by the nominal impedance to give "max watts". See AES-2 1984
> "Speaker Testing" link 2.
>
> As a result of this patent absurdity - the actual watts dissipated by
> the speaker during such testing may well be only 20 to 25% of the
> published max watts figure."
>
>
> I assume trying to calculate Power from Voltage x Current by
> putting a current sensing resistor of 0.1 Ohm in series with the
> speaker under test, would affect the measurements too much?
>

** Wrong.

Power = V x I only for resistive loads.

The actual dissipation can be found by measuring the power leaving the test amplifier - and that requires a wide band wattmeter.

> How hot is a "dangerously hot" voice coil? :)
>

** Hot as it can be without risk of sudden failure.

>
> Seems to me the best thing to do would be to measure
> the RMS voltages, while incrementally increasing the pink noise output
> level from the amplifier, until the speakers blows. Then you
> could use the last measured RMS voltage (when the speaker still
> survived) in the calculation.
>

** Some makers might do that - but the speaker must survive a couple of hours
at the rated figure and all examples sold be able to pass the same test.

Is there any point to you meanderings?



.... Phil

[Phil Allison]

Paul wrote:


>
> How about if I took a Celestion G12P-80 speaker that I took out
> of a broken Line 6 guitar amplifier, and slapped it into this JBL
> Control 12SR?
>

** The Celestion guitar speaker has higher efficiency in the mid and upper ranges so would sound wrong, plus in that tiny enclosure would have no deep bass - plus way less power handling.

The performance would be ruined compared to the original JBL woofer.




.... Phil

[Paul]

On 2/8/2017 4:26 PM, Mike Rivers wrote:
> On 2/8/2017 5:54 PM, Paul wrote:
>> I wasn't talking to you, dumbshit....
>
> And I wasn't talking to you, I was making a pronouncement to the world.
> You just happened to be there and had your eyes turned on. Try turning
> on your ears, though, when you install the new speaker.
>

Try turning on your brain, Motherfucker....how's that for a
pronouncement?

:)

[Paul]

On 2/8/2017 5:25 PM, Phil Allison wrote:
> Paul wrote:
> Phil Allison wrote:
>>
>>>
>>> Section 3.2 of my article on speaker failures makes the case pretty clear.
>>>
>>> http://sound.whsites.net/articles/speaker-failure.html
>>>
>>
>>
>> From your link: "Nominal Impedance = R plus 15% - where R is the
>> DC resistance in ohms
>>
>> The "nominal impedance" of a woofer or instrument speaker is the
>> LOWEST value of the REAL impedance that driver exhibits in the audio
>> range and at room temperature. The actual minimum typically occurs in
>> the band between 200 Hz and 500 Hz and the usual test frequencies are
>> 250 Hz or 400 Hz.
>>
>> Being an impedance minimum means that it is a pure resistance too, with
>> current and voltage in phase. The extra 15% comes from energy losses in
>> the suspension, eddy currents the iron magnet structure and radiated sound."
>>
>>
>> So this estimated nominal impedance ignores the inductive
>> reactance of the voice coil, because it assumes lower testing
>> frequencies, where XL=2pifL will be low, and can be ignored?
>>
>
> ** Nope - it ignores nothing.
>
> Read what you just quoted, the MINIMUM lies between two rises in impedance at low and high frequencies. How else could it be a minimum ?
>

But you state in your link that "A "nominal watt" is based purely

on a simple, but absurd, calculation that assumes the speaker maintains
it nominal impedance at all frequencies and under all operating conditions."

So you yourself are saying that it's very rough guestimate! You
are measuring the DC resistance, and just slapping on 15% indiscriminately!

Yes, to learn from people who only think they
know everything already!

:)


>
>
>
> .... Phil
>
>

[Paul]

Alright, since you have made the only real suggestion:


http://www.parts-express.com/jbl-2206h-12-high-power-lf-driver--294-480


$450! I could easily buy a new pair of PA cabs for that!

The shipping better be free for that price!

There's gotta be a cheaper equivalent!

:(

[Scott Dorsey]

In article <o7gf01$22o$1...@dont-email.me>, Paul <quill...@gmail.com> wrote:
>
> The shipping better be free for that price!
>
> There's gotta be a cheaper equivalent!

You mean like getting the OEM driver from JBL? Or maybe you mean like
getting the existing one reconed.

I don't know why you're talking about making all of these horribly makeshift
substitutions when just doing it properly isn't very expensive or difficult.

[Phil Allison]

Paul wrote:


> >>>
> >>> Section 3.2 of my article on speaker failures makes the case pretty clear.
> >>>
> >>> http://sound.whsites.net/articles/speaker-failure.html
> >>>
> >>
> >>> From your link: "Nominal Impedance = R plus 15% - where R is the
> >> DC resistance in ohms
> >>
> >> The "nominal impedance" of a woofer or instrument speaker is the
> >> LOWEST value of the REAL impedance that driver exhibits in the audio
> >> range and at room temperature. The actual minimum typically occurs in
> >> the band between 200 Hz and 500 Hz and the usual test frequencies are
> >> 250 Hz or 400 Hz.
> >>
> >> Being an impedance minimum means that it is a pure resistance too, with
> >> current and voltage in phase. The extra 15% comes from energy losses in
> >> the suspension, eddy currents the iron magnet structure and radiated sound."
> >>
> >>
> >> So this estimated nominal impedance ignores the inductive
> >> reactance of the voice coil, because it assumes lower testing
> >> frequencies, where XL=2pifL will be low, and can be ignored?
> >>
> >
> > ** Nope - it ignores nothing.
> >
> > Read what you just quoted, the MINIMUM lies between two rises in impedance at low and high frequencies. How else could it be a minimum ?
> >
>
> But you state in your link that "A "nominal watt" is based purely
> on a simple, but absurd, calculation that assumes the speaker maintains
> it nominal impedance at all frequencies and under all operating conditions."
>
> So you yourself are saying that it's very rough guestimate!

** You have a reading problem.

Nominal impedance = the figure the maker supplies.

Wattage specifications are calculated based on this number and the voltage applied during testing. So the watts are nominal watts, not real ones.

> You
> are measuring the DC resistance, and just slapping on 15% indiscriminately!

** What does my article say ??

I see you have a bad dose of ADHD.




.... Phil

[Paul]

On 2/8/2017 6:21 PM, Phil Allison wrote:

>
>> You
>> are measuring the DC resistance, and just slapping on 15% indiscriminately!
>
>
> ** What does my article say ??
>

Not very much, apparently!

[geoff]

On 9/02/2017 2:02 p.m., Paul wrote:
>
>
>
> http://www.parts-express.com/jbl-2206h-12-high-power-lf-driver--294-480
>
>
> $450! I could easily buy a new pair of PA cabs for that!
>
> The shipping better be free for that price!
>
> There's gotta be a cheaper equivalent!
>
> :(
>

Go to eBay, search JBL Control 12SR. Re-cone kits and whole speaker there.

geoff

[Paul]

Except I opened it up just today, and....it's an old Electro Voice
SRO/12!

Definitely not the original speaker! It was hanging on by only
two screws as well! Haha! :)

Only rated for 60 Watts continuous sine wave:


https://www.manualslib.com/manual/43766/Electro-Voice-Sro-12.html


So it's probably not worth re-coning for my purposes.

I'm gonna throw in the Celestion, and see if it's good enough
for me!

I know many of you are in high-end studios, so you are obligated
to give the best advice, cost be damned, but I ain't spending $450
just to get this thing running again!

:/

[Phil Allison]

Paul wrote:
>
> >> You
> >> are measuring the DC resistance, and just slapping on 15% indiscriminately!
> >
> >
> > ** What does my article say ??
> >
>
> Not very much, apparently!

** The explanation is there to be read, I not gonna repeat it over and over for you.

ADHD does no stop you from reading something a few times.

But is sure fucks comprehension up.


...... Phil

[Phil Allison]

Paul wrote:
>
>
>
> Except I opened it up just today, and....it's an old Electro Voice
> SRO/12!
>
> Definitely not the original speaker! It was hanging on by only
> two screws as well! Haha! :)
>
> Only rated for 60 Watts continuous sine wave:
>
>
> https://www.manualslib.com/manual/43766/Electro-Voice-Sro-12.html
>
>

** That was a great guitar speaker in its day.

Alnico magnet, 2.5 inch VC, 103dB/watt sensitivity and rated for CONTINUOUS sine wave power of 60 watts rms !!

Be rated at 250 watts by most makers today.

Ought to be worth re-coning.


.... Phil

[Paul]

Your article doesn't say shit....just measure DC resistance and
add 15%!

VERY primitive, and foolish....

[Phil Allison]

** It also gives all the reasons - you lying pig.


FYI:

The figure of +15% is an international standard for quoting " nominal impedance " - based on a statistical analysis of the DC resistance v minimum AC impedance of many speakers.



.... Phil

[Paul]

Ok, just tried the Celestion out: SM58 into a Mackie 406M into 12SR.

And.....it's pretty good... I've heard worse, and I've heard
better. A bit of distortion somewhere in the midrange, but not
horrible.

I could probably sell it, and just buy a whole new cab.

:/

haha!

[JackA]

Best watch it, their NONE attack dog will be chewing at your leg! :-)

Jack

[Paul]

NOT BEFORE I SHOOT IT DEAD!

BRING IT ON, MOTHER-FUCKERS!

HAHAHHAAAA!!!

:)

[Mike Rivers]

On 2/8/2017 9:47 PM, Paul wrote:
>> Go to eBay, search JBL Control 12SR. Re-cone kits and whole speaker
>> there.

> Except I opened it up just today, and....it's an old Electro Voice
> SRO/12!
>
> Definitely not the original speaker! It was hanging on by only two
> screws as well! Haha! :)
>
> Only rated for 60 Watts continuous sine wave:

And all the time that it was working, it sounded fine to you? If so, QED

[Scott Dorsey]

Indeed, but it doesn't belong in that cabinet. It is likely worth reconing
and putting in a guitar cabinet and then buying the proper replacement driver
for the Control 12. The original poster STILL hasn't priced out the cost of
the original driver. It won't be that much.

However, if someone has messed up the thing by putting a totally inappropriate
replacement in there, who knows what else is wrong with it?

[Paul]

On 2/9/2017 5:23 AM, Mike Rivers wrote:
> On 2/8/2017 9:47 PM, Paul wrote:
>>> Go to eBay, search JBL Control 12SR. Re-cone kits and whole speaker
>>> there.
>
>> Except I opened it up just today, and....it's an old Electro Voice
>> SRO/12!
>>
>> Definitely not the original speaker! It was hanging on by only two
>> screws as well! Haha! :)
>>
>> Only rated for 60 Watts continuous sine wave:
>
> And all the time that it was working, it sounded fine to you? If so, QED
>

This was just given to me for free....now i know why!

:/

[Paul]

I'll tell you what else!

The tweeter horn is "A Product of Peavey Electronics," with NO
crossover in sight, except a 5.6uF cap in series!

No wonder the adjustable High frequency rolloff knob at the top
was completely missing! It is labeled, but only the hole for the
pot remains!

Perhaps I could make this sound a bit better with a crossover
more like the original?

I'll probably sell this, and get a new or newer JBL or Mackie
cab.

Sorry for making such an amateur thread! I do appreciate you
professionals' time!

I haven't been able to find an original driver....will keep looking....

[Mike Rivers]

On 2/9/2017 12:25 PM, Paul wrote:
> This was just given to me for free....now i know why!

But think of all the fun you've had. ;)

[geoff]

An extra port ?

>
> Perhaps I could make this sound a bit better with a crossover
> more like the original?
>
> I'll probably sell this, and get a new or newer JBL or Mackie
> cab.
>
> Sorry for making such an amateur thread! I do appreciate you
> professionals' time!
>
> I haven't been able to find an original driver....will keep looking....
>

Maybe start producing this combination as your own product. Clearly it
worked well ....

geoff

[Scott Dorsey]

In article <o7i98e$kmm$1...@dont-email.me>, Paul <quill...@gmail.com> wrote:
>
> The tweeter horn is "A Product of Peavey Electronics," with NO
>crossover in sight, except a 5.6uF cap in series!

Well, that likely explains why the woofer failed, if it was an ovexcursion
failure.

> I'll probably sell this, and get a new or newer JBL or Mackie
>cab.

Please don't sell it. Don't pass your grief on to others. Put it in the
crusher.

> I haven't been able to find an original driver....will keep looking....

Call a JBL dealer, they will be able to get them. However, if you ALSO have
to replace the horn, compression driver, and crossover, it's not worth it.
I think it's time for the crusher.

[Neil]

Cut your losses. If you want to have that particular JBL speaker, there
are places to buy used ones on-line. But, by the time you spend the
money purchasing the unit and getting it to you, it might be better to
invest in something that you can actually maintain.

If there's an upside, it might be that you'll be extremely pleased by
the sound of a genuine JBL unit.

--
best regards,

Neil

[Paul]

Well, as I mentioned, SM58 into a Mackie 406M into the 12SR with
Celestion and Peavey tweeter horn was NOT HORRIBLY BAD!

It was pretty good sounding. It didn't blow me away, but I've also
heard much worse. There seemed to be a bit of distortion in the
midrange maybe.

Would getting a cheap speaker crossover on Ebay possibly clean
up the sound a bit? Again, it only has a 5.6uF cap in series with
the tweeters.....

[Paul]

On 2/9/2017 11:41 AM, Mike Rivers wrote:
> On 2/9/2017 12:25 PM, Paul wrote:
>> This was just given to me for free....now i know why!
>
> But think of all the fun you've had. ;)
>

Very True!

:)

[Mike Rivers]

On 2/9/2017 6:22 PM, Paul wrote:
> Would getting a cheap speaker crossover on Ebay possibly clean
> up the sound a bit? Again, it only has a 5.6uF cap in series with
> the tweeters.....

Doubt it. The capacitor protects the tweeter from getting woofed at. The
woofer won't reproduce the tweets, so the only other thing you can add
to it is an inductor to keeps the tweets from wasting some power trying
to drive the woofer, not much to gain there.

To build a more sophisticated crossover, you'd need to know more about
the characteristics of the speakers in order to know where to cross them
over.

[Paul]

Ok, thank you.

I did some more testing using one of my Yamaha HS80Ms, A/B
comparison using the monitor lineout to the Yamaha, main to the 12SR.

Again, this Frankenstein cab is pretty decent sounding. The HS80M
is cleaner, of course, and the JBL cab has a thicker bottom end, but
again, I have heard much worse. Some of the distortion I heard with the
SM58 was due to proximity effects near the microphone, and was also
heard on the HS80M.

I repeated the test with an AT4047, with similar results.

But testing by singing into a mic is a bit difficult, because
you hear your own voice through your bones. So I'm going to do more
tests using Pink Floyd's Dark Side of the Moon, using the tape/CD
inputs, to get a more objective test.

Stay tuned...

:)

[Trevor]

On 9/02/2017 1:17 AM, Scott Dorsey wrote:
> In article <o7e0jf$41d$1...@dont-email.me>, Paul <quill...@gmail.com> wrote:
>> They could then establish a Mean Time before Failure (MTBF), and
>> say statistically that you could use this speaker with this amp, and
>> expect an average of this many hours of usage before blowing the speaker.
>
> The only person who has ever even made a stab at that sort of thing is
> Wolfgang Klippel. Klippel has done more to establish statistical quality
> control of speaker drivers than anyone else ever, I suspect.

Is Dick Pierce still with us?

Trevor.

[Trevor]

On 10/02/2017 4:36 AM, Paul wrote:
> I'll tell you what else!
>
> The tweeter horn is "A Product of Peavey Electronics," with NO
> crossover in sight, except a 5.6uF cap in series!

That *IS* a 6db/oct High pass filter/crossover!
The absolute minimum required to stop the horn instantly blowing up of
course.

I wonder what happened to all the original JBL parts though.

> I'll probably sell this, and get a new or newer JBL or Mackie
> cab.

I sure hope you don't try to pass it off as a JBL 12SR then.

Trevor.

[Trevor]

On 10/02/2017 10:59 AM, Mike Rivers wrote:
> On 2/9/2017 6:22 PM, Paul wrote:
>> Would getting a cheap speaker crossover on Ebay possibly clean
>> up the sound a bit? Again, it only has a 5.6uF cap in series with
>> the tweeters.....
>
> Doubt it. The capacitor protects the tweeter from getting woofed at. The
> woofer won't reproduce the tweets, so the only other thing you can add
> to it is an inductor to keeps the tweets from wasting some power trying
> to drive the woofer, not much to gain there.

From his description there may well be something to gain by getting rid
of some midrange going to the woofer, which is probably part of the
crook midrange he is describing. May well be a big midrange peak with
both speakers operating in that band if the woofer isn't naturally
rolling off quick enough for such a simple xover network. Add to that
the horn is probably far more efficient than the woofer and thus would
need to be attenuated, NOT just a capacitor.

However having no original JBL parts and no ability to test it properly
in it's new guise sounds like an audio nightmare to me.
Looks like he is just going to inflict it on some other poor sap.

Trevor.

[Paul]

On 2/9/2017 9:26 PM, Trevor wrote:
> On 10/02/2017 4:36 AM, Paul wrote:
>> I'll tell you what else!
>>
>> The tweeter horn is "A Product of Peavey Electronics," with NO
>> crossover in sight, except a 5.6uF cap in series!
>
> That *IS* a 6db/oct High pass filter/crossover!
> The absolute minimum required to stop the horn instantly blowing up of
> course.

Of course you are correct, that's a first order high pass filter,
-6dB/Octave or -20 dB/decade.

But my idea of a proper crossover includes some low pass filtering
to the woofer, of which there is absolutely nothing in this cab
at all!

>
> I wonder what happened to all the original JBL parts though.
>

Probably taken out with the original JBL tweeters, when they
blew out!

>
>> I'll probably sell this, and get a new or newer JBL or Mackie
>> cab.
>
> I sure hope you don't try to pass it off as a JBL 12SR then.
>

I won't. I'll probably keep this for my own usage. You don't need
high end equipment to have a backyard jam session!

[Paul]

Does anyone have a schematic of the original, sweep-able crossover
for this cab?

I was not able to find anything on the net...

[Phil Allison]

Paul wrote:
>
>
> > the horn is probably far more efficient than the woofer and thus would
> > need to be attenuated, NOT just a capacitor.
> >
> > However having no original JBL parts and no ability to test it properly
> > in it's new guise sounds like an audio nightmare to me.
> > Looks like he is just going to inflict it on some other poor sap.
> >
>
> Does anyone have a schematic of the original, sweep-able crossover
> for this cab?
>

** The JBL x-over is not "sweepable".

You do not have the original JBL components, so have no need to duplicate the original x-over.

Designing a suitable x-over is a job for someone with expertise - so not you.



.... Phil

[Paul]

On 2/9/2017 10:19 PM, Phil Allison wrote:
> Paul wrote:
>>
>>
>>> the horn is probably far more efficient than the woofer and thus would
>>> need to be attenuated, NOT just a capacitor.
>>>
>>> However having no original JBL parts and no ability to test it properly
>>> in it's new guise sounds like an audio nightmare to me.
>>> Looks like he is just going to inflict it on some other poor sap.
>>>
>>
>> Does anyone have a schematic of the original, sweep-able crossover
>> for this cab?
>>
>
>
> ** The JBL x-over is not "sweepable".

There was a pot to adjust the high end roll off, so that's
sweepable, you dumbshit!

>
> You do not have the original JBL components, so have no need to duplicate the original x-over.
>
> Designing a suitable x-over is a job for someone with expertise - so not you.
>

Fuck you, bitch. I've designed RF filters, so this wouldn't be a
huge stretch.

And if you took your fucked up head out of your ass, you would
realize I was ASKING FOR A FUCKING SCHEMATIC, WHICH IS ALREADY DESIGNED,
DUMBFUCK!

BOY, YOU ARE STUPID!

[Phil Allison]

Paul the Nutter wrote:


> >>
> >> Does anyone have a schematic of the original, sweep-able crossover
> >> for this cab?
> >>
> >
> >
> > ** The JBL x-over is not "sweepable".
>
> There was a pot to adjust the high end roll off,

** Wrong. There was an attenuator for tweeter level.


> so that's sweepable,

** Like hell.


>>you dumbshit!


** You are a lying, brain dead pig.

>
> > You do not have the original JBL components, so have no need to duplicate the original x-over.
> >
> > Designing a suitable x-over is a job for someone with expertise - so not you.
> >
>
> Fuck you, bitch.

** You are worse the a stupid, lying pig.

> I've designed RF filters,

** No you haven't.

> so this wouldn't be a
> huge stretch.

** It's way beyond an asswipe like you.

>
> And if you took your fucked up head out of your ass, you would
> realize I was ASKING FOR A FUCKING SCHEMATIC, WHICH IS ALREADY DESIGNED,
> DUMBFUCK!
>

** I pointed out why it is NO use to you.

You stupid, lying, fucking asswipe.



.... Phil

[Paul]

On 2/9/2017 10:57 PM, Phil Allison wrote:
> Paul the Nutter wrote:
>
>
>>>>
>>>> Does anyone have a schematic of the original, sweep-able crossover
>>>> for this cab?
>>>>
>>>
>>>
>>> ** The JBL x-over is not "sweepable".
>>
>> There was a pot to adjust the high end roll off,
>
> ** Wrong. There was an attenuator for tweeter level.
>

Perhaps. Do you have a sample schematic that shows this?

>
> > so that's sweepable,
>
> ** Like hell.
>
>
> >>you dumbshit!
>
>
> ** You are a lying, brain dead pig.
>
>
>
>>
>>> You do not have the original JBL components, so have no need to duplicate the original x-over.
>>>
>>> Designing a suitable x-over is a job for someone with expertise - so not you.
>>>
>>
>> Fuck you, bitch.
>
>
> ** You are worse the a stupid, lying pig.
>
>
>> I've designed RF filters,
>
> ** No you haven't.
>

Yes, I have, using ADS and Microwave Office. Edge-coupled filters
on alumina stable. Lumped element filters too. 0.5-40 GHz.

>> so this wouldn't be a
>> huge stretch.
>
>
> ** It's way beyond an asswipe like you.

Audio frequencies are a cakewalk compared to GHz!

>
>
>>
>> And if you took your fucked up head out of your ass, you would
>> realize I was ASKING FOR A FUCKING SCHEMATIC, WHICH IS ALREADY DESIGNED,
>> DUMBFUCK!
>>
>
>
> ** I pointed out why it is NO use to you.
>
> You stupid, lying, fucking asswipe.
>

Hahaha! I know your type well! An old fart, way past his prime,
and DESPERATE FOR ATTENTION BECAUSE HE NEVER MADE A MARK ON THE INDUSTRY!

Ok, since you are so desperate to show off: Tell us how you would
design a crossover, if given the spec sheets for the tweeters and woofer?

I'm all ears, BUTT-FUCKER!

:)

[Phil Allison]

Paul wrote:

>
> >>>
> >>> ** The JBL x-over is not "sweepable".
> >>
> >> There was a pot to adjust the high end roll off,
> >
> > ** Wrong. There was an attenuator for tweeter level.
> >
>
> Perhaps. Do you have a sample schematic that shows this?
>

>

** Says so in the data sheet - asswipe.

> >>
> >>> Designing a suitable x-over is a job for someone with expertise - so not you.
> >>>
> >>
> >> Fuck you, bitch.
> >
> >
> > ** You are worse the a stupid, lying pig.
> >
> >
> >> I've designed RF filters,
> >
> > ** No you haven't.
> >
>
> Yes, I have, using ADS and Microwave Office.

** Yawnnnnnnnnn........

> >
> > ** It's way beyond an asswipe like you.
>
> Audio frequencies are a cakewalk compared to GHz!

** Totally separate topics - asswipe.

Audio ain't simple when you are a clueless idiot.

>
> >
> >>
> >> And if you took your fucked up head out of your ass, you would
> >> realize I was ASKING FOR A FUCKING SCHEMATIC, WHICH IS ALREADY DESIGNED,
> >> DUMBFUCK!
> >>
> >
> >
> > ** I pointed out why it is NO use to you.
> >
> > You stupid, lying, fucking asswipe.
> >
>
> Hahaha!

** Go fuck yourself - asswipe.

> Ok, since you are so desperate to show off: Tell us how you would
> design a crossover, if given the spec sheets for the tweeters and woofer?
>

** I know exactly how to, long as I have the drivers in my possession and can run tests. Spec sheets do not contain adequate info.


You stupid, know nothing, bullshitting, TROLLING ASSWIPE !!!



.... Phil

[Paul]

On 2/9/2017 11:52 PM, Phil Allison wrote:

>>>
>>>
>>>> I've designed RF filters,
>>>
>>> ** No you haven't.
>>>
>>
>> Yes, I have, using ADS and Microwave Office.
>
> ** Yawnnnnnnnnn........

Haha! Never used either program, right?

BWHAHA!

>
>
>
>>>
>>> ** It's way beyond an asswipe like you.
>>
>> Audio frequencies are a cakewalk compared to GHz!
>
>
> ** Totally separate topics - asswipe.
>
> Audio ain't simple when you are a clueless idiot.
>
>>
>>>
>>>>
>>>> And if you took your fucked up head out of your ass, you would
>>>> realize I was ASKING FOR A FUCKING SCHEMATIC, WHICH IS ALREADY DESIGNED,
>>>> DUMBFUCK!
>>>>
>>>
>>>
>>> ** I pointed out why it is NO use to you.
>>>
>>> You stupid, lying, fucking asswipe.
>>>
>>
>> Hahaha!
>
>
> ** Go fuck yourself - asswipe.
>
>
>> Ok, since you are so desperate to show off: Tell us how you would
>> design a crossover, if given the spec sheets for the tweeters and woofer?
>>
>
> ** I know exactly how to, long as I have the drivers in my possession and can run tests. Spec sheets do not contain adequate info.
>

OK, THEN TELL US HOW YOU DO IT, MR. KNOW-IT-ALL!

CAN'T CAN YOU! THAT'S BECAUSE YOU DON'T KNOW SHIT!

HAHA! :)

[Paul]

On 2/9/2017 9:39 PM, Trevor wrote:

I imagine this site is too simplistic:

http://www.apicsllc.com/apics/Misc/filter2.html

[Phil Allison]

Paul the Criminal Fuckwit Troll wrote:

>
>
> >
> >>>> I've designed RF filters,
> >>>
> >>> ** No you haven't.
> >>>
> >>> >> Yes, I have, using ADS and Microwave Office.
> >
> > ** Yawnnnnnnnnn........
>
> Haha!

** Go straight to hell - fuckwit.

The software did the design - not you, asswipe !!

> >
> >> Ok, since you are so desperate to show off: Tell us how you would
> >> design a crossover, if given the spec sheets for the tweeters and woofer?
> >>
> >
> > ** I know exactly how to, long as I have the drivers in my possession and can run tests. Spec sheets do not contain adequate info.
> >
>
> OK, THEN TELL US HOW YOU DO IT, MR. KNOW-IT-ALL!

** What the fucking hell for ?????

You would have NO way of knowing if what I posted was correct or not.

Go fuck your ugly, retarded mother - asswipe.






..... Phil

[Trevor]

On 10/02/2017 4:04 PM, Paul wrote:
> On 2/9/2017 9:26 PM, Trevor wrote:
>> On 10/02/2017 4:36 AM, Paul wrote:
>>> I'll tell you what else!
>>> The tweeter horn is "A Product of Peavey Electronics," with NO
>>> crossover in sight, except a 5.6uF cap in series!
>>
>> That *IS* a 6db/oct High pass filter/crossover!
>> The absolute minimum required to stop the horn instantly blowing up of
>> course.
>
> Of course you are correct, that's a first order high pass filter,
> -6dB/Octave or -20 dB/decade.
>
> But my idea of a proper crossover includes some low pass filtering
> to the woofer, of which there is absolutely nothing in this cab
> at all!

JBL themselves made speakers with no crossover components to the woofer.
In the right circumstances it is actually a benefit.
I'd be more worried that the horn HP filter is only 6dB/oct. that rarely
works well IME. Especially with no sign of any attempt to match speaker
sensitivities. Unlikely the woofer is as efficient as the horn.

Trevor.

[Trevor]

You have the spec sheets for YOUR tweeter and Woofer? And they show ALL
necessary information and measurements to properly design a suitable
crossover? Or you are able to make those proper measurements yourself?
Sounds unlikely to me or you wouldn't have asked the question you did in
the first place!

Trevor.

[Trevor]

Short answer, yes, for your purpose.

Trevor

[Paul]

On 2/10/2017 12:12 AM, Phil Allison wrote:
> Paul the Criminal Fuckwit Troll wrote:
>
>>
>>
>>>
>>>>>> I've designed RF filters,
>>>>>
>>>>> ** No you haven't.
>>>>>
>>>>>>> Yes, I have, using ADS and Microwave Office.
>>>
>>> ** Yawnnnnnnnnn........
>>
>> Haha!
>
>
> ** Go straight to hell - fuckwit.
>
> The software did the design - not you, asswipe !!

HEY FUCKTARD, THE SOFTWARE DOESN'T KNOW IT'S OWN LIMITATIONS...THE
USER HAS TO KNOW THAT, AND HOW TO USE THE PROGRAM. THAT TAKES
KNOWLEDGE, SHIT-WIT!

AND WHAT DUMB-FUCK IS GOING TO CALCULATE AND OPTIMIZE BY HAND,
A 2.5D FINITE ELEMENT ANALYSIS, CONFORMAL MESH? ONLY A FUCKTARD THAT
WANTS TO WASTE HIS TIME, AND THE COMPANY'S TIME!

BUT YOU DON'T KNOW WHAT THE FUCK I'M TALKING ABOUT ANYWAYS, SO
FUCK OFF!

>
>
>
>>>
>>>> Ok, since you are so desperate to show off: Tell us how you would
>>>> design a crossover, if given the spec sheets for the tweeters and woofer?
>>>>
>>>
>>> ** I know exactly how to, long as I have the drivers in my possession and can run tests. Spec sheets do not contain adequate info.
>>>
>>
>> OK, THEN TELL US HOW YOU DO IT, MR. KNOW-IT-ALL!
>
>
> ** What the fucking hell for ?????
>
> You would have NO way of knowing if what I posted was correct or not.
>
> Go fuck your ugly, retarded mother - asswipe.
>

I'LL PISS ON YOUR MOMMA'S GRAVE FIRST, AND THEN SHIT DOWN YOUR
THROAT, BITCH MOTHER-FUCKER!

GO BACK TO FUCKING YOUR DADDY'S PUSSY, YOU FAGGOT-ASS FUCK-FACE!

:)

[Paul]

No shit, Sherlock!

Gee....maybe if I knew the answer myself, I wouldn't ask the
question?

How would YOU design a crossover?

[Paul]

Ok, what is the long answer?

What order filter should I use and why?

Linkwitz-Riley, Butterworth, or Bessel?

How do you pick the optimum crossover frequency?

[Phil Allison]

Paul the PSYCHOPATHIC Fuckwit Troll wrote:

>
> >>
> >>
> >>>
> >>>>>> I've designed RF filters,
> >>>>>
> >>>>> ** No you haven't.
> >>>>>
> >>>>>>> Yes, I have, using ADS and Microwave Office.
> >>>
> >>> ** Yawnnnnnnnnn........
> >>
> >> Haha!
> >
> >
> > ** Go straight to hell - fuckwit.
> >
> > The software did the design - not you, asswipe !!
>
> HEY FUCKTARD,

** Go fuck your ugly, autistic whore mother.

> >
> >>> ** I know exactly how to, long as I have the drivers in my possession and can run tests. Spec sheets do not contain adequate info.
> >>>
> >>
> >> OK, THEN TELL US HOW YOU DO IT, MR. KNOW-IT-ALL!
> >
> >
> > ** What the fucking hell for ?????
> >
> > You would have NO way of knowing if what I posted was correct or not.
> >
> > Go fuck your ugly, retarded mother - asswipe.
> >
>
> I'LL PISS ON YOUR MOMMA'S GRAVE FIRST,

** Then fuck your ugly, fuckwit whore mother.

For good luck.



.... Phil

[Phil Allison]

Paul the Psycho TROLL wrote:
>
>
> >
> > Short answer, yes, for your purpose.
> >
>
> Ok, what is the long answer?
>
> What order filter should I use and why?
>
> Linkwitz-Riley, Butterworth, or Bessel?
>
> How do you pick the optimum crossover frequency?
>

** Designing such a x-over network is an engineering problem to be analysed and solved with the particular components on hand in a well equipped, audio electronics workshop environment - not a series of simple dumb Qs to be answered.

But the brain dead CUNT asking here could not understand or even believe that fact even if it were given a thousand centuries to do so.

Only thing the vile POS is any good at is fucking his ugly mum.





.... Phil