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hissing sound coming from behind woofer on one side AR11

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Amanda Ripanykhazov

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Jul 20, 2010, 3:30:48 PM7/20/10
to
Anyone know what this means? This hissing sound isnt constant, it is
irregular: It isnt related to the music or any movement of the cone
or any signal put through it, though it doesnt happen when no sound is
put through the speaker.

Frankly it sounds more mechancial than electronic (as if there is
something behind there!) but as I say, it isnt related to whatever is
coming through the speaker though it does increase and decrease with
adjustment of the volume control. Andit is louder than most signals
put through the woofer itself??

Is it indicative of some pot in the crossover needing cleaning or is
there something else going on please? (I have seen reference to people
improving the sound of AR11s by bypassing the tone controls in the
speaker completely). This speaker is quite elderly and I would
imagine that if it does use mechanical pots, they must be fairly dirty
by now

GregS

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Jul 20, 2010, 4:04:34 PM7/20/10
to

Looks like a closed box and my first thought is an leak. Don't understand"behind woofer"
Inside ?? Outside ?? Or sounds like behind woofer from the front.

I would troubleshoot a woofer with low frequency test tones, without
any high frequencies being generated. I used to do a quick test with AM radio.

Changing frequency will likely change the sound. Get close, feel around.
Can't tell from your description, but could be the woofer itself making
mechanical surround, voice coil, or suspension sounds.

greg

William Sommerwerck

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Jul 20, 2010, 4:20:44 PM7/20/10
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If the AR11 were a ducted-port speaker (I don't think it is), it would
likely be the "port noise complaint" (OUCH!), with air "rushing" or
"whistling" through the port.

It's hard to believe the sound /is/ coming from the speaker when you say "it
isn't related to the music or any movement of the cone or any signal put
through it". Speakers are passive, and do not produce sounds on their own --
other than, perhaps, loud crashing/breaking noises when they're knocked off
a shelf.


Meat Plow

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Jul 20, 2010, 4:57:56 PM7/20/10
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Make sure a snake hasn't crawled behind the speaker.

Franc Zabkar

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Jul 20, 2010, 5:45:36 PM7/20/10
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On Tue, 20 Jul 2010 20:57:56 +0000 (UTC), Meat Plow
<mhy...@yahoo.com> put finger to keyboard and composed:

>Make sure a snake hasn't crawled behind the speaker.

http://farm1.static.flickr.com/58/201963991_64a75623ae.jpg

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.

Reverend Fuzzy

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Jul 20, 2010, 7:39:06 PM7/20/10
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On Jul 20, 2:30 pm, Amanda Ripanykhazov <dmanzal...@googlemail.com>
wrote:

If there is a cross-over board in the case, you may have an
electrolytic capacitor going bad.
When they over heat, they'll make those sort of noises.

Phil Allison

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Jul 20, 2010, 7:46:59 PM7/20/10
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"Reverend Fuzzy"

If there is a cross-over board in the case, you may have an
electrolytic capacitor going bad.
When they over heat, they'll make those sort of noises.

** That is utterly bizarre crap.


.... Phil


Jim Adney

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Jul 20, 2010, 9:01:12 PM7/20/10
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On Jul 20, 2:30 pm, Amanda Ripanykhazov <dmanzal...@googlemail.com>
wrote:

> Anyone know what this means? This hissing sound isnt constant, it is


> irregular:  It isnt related to the music or any movement of the cone
> or any signal put through it, though it doesnt happen when no sound is
> put through the speaker.
>
> Frankly it sounds more mechancial than electronic (as if there is
> something behind there!) but as I say, it isnt related to whatever is
> coming through the speaker though it does increase and decrease with
> adjustment of the volume control.  Andit is louder than most signals
> put through the woofer itself??

My guess is that the suspension for the woofer cone has come unglued.
This can allow the voice coil to rub on the magnet, which makes sounds
that are mechanical and vary with volume.

To check for this, you'll need to remove the grill cloth so you can
get to the speakers. Gently press all five fingers of one hand against
the woofer cone, next to the center dome. Push sideways on the cone;
try several directions. It should not want to move. It may be useful
to do this on both speaker (stereo, right?) so you can be sure of any
differences.

You may see that the "surround" has disintegrated. That would be an
obvious flaw. There is also a lower support called a spider which
centers the cone near its small end. If the spider has come unglued,
it can be reglued while holding the cone centered.

Older AR speakers used wirewound controls for the tone controls. These
corrode and lose contact. The effect of this is to lose the midrange
or tweeter completely. They can be disassembled and cleaned, but they
don't tend to make extra noises. The capacitors in decent speaker
crossovers are never electrolytics, so they don't generally
deteriorate over time.

Reverend Fuzzy

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Jul 20, 2010, 9:38:52 PM7/20/10
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Not half as bizarre as your instant flaming of something I have seen
happen in my personal experience. If you haven't seen it, yourself,
don't just call my answer crap... PROVE it can't happen.

Phil Allison

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Jul 20, 2010, 9:41:53 PM7/20/10
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"Jim Adney"


You may see that the "surround" has disintegrated.

** Happens to ALL speakers made with foam surrounds - like the AR11.


That would be an obvious flaw.

** Obvious only if you look, the OP must be blind.


If the spider has come unglued,

** Very unlikely.


Older AR speakers used wirewound controls for the tone controls.

** Not the AR 11 - it uses a switch.

The capacitors in decent speaker
crossovers are never electrolytics,


** Fraid that is just not true.

Most famous brand name hi-fi speakers use bi-polar electros for the larger
values at least.

.... Phil

Phil Allison

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Jul 20, 2010, 9:47:19 PM7/20/10
to

"Reverend Fuzzy"
"Phil Allison"

>
> If there is a cross-over board in the case, you may have an
> electrolytic capacitor going bad.
> When they over heat, they'll make those sort of noises.
>
> ** That is utterly bizarre crap.

Not half as bizarre as your instant flaming of something I have seen
happen in my personal experience.

** What you wrote here is bizarre crap.

What you might have seen elsewhere at sometime is another matter.


If you haven't seen it, yourself,


** Your post here is bizarre crap.

Electros used in hi-fi speakers like the AR11 do not "over heat" and hence
are not the source of peculiar hissing noises.

Ever worked on an AR11??

I have.


.... Phil


William Sommerwerck

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Jul 21, 2010, 7:21:50 AM7/21/10
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> The capacitors in decent speaker crossovers are never
> electrolytics, so they don't generally deteriorate over time.

Never? I haven't checked "decent" speakers lately, but the AR11 is from an
era when non-polar electrolytics were commonly used. Even inexpensive Mylar
caps cost more than electrolytics.

The tendency toward two-way designs (the AR11 is three-way) has raised the
crossover point to a frequency that makes the use of a film cap
more-practical. But even "the" classic two-way speaker (The Advent Speaker)
used an electrolytic.

The DQ-10 was one of the first speakers to use film caps. The original
version used mostly electrolytics; the changeover occurred several years
into production. In exchange for loaning him a pair of Pearl mics, Jon sent
me a box of cheap Mexican Mylar caps, and I repopulated the crossovers. I
was in such a rush to get it all done, that I didn't leave one of my four
DQ-10s unmodded, and wasn't able to make a valid comparison.

I /was/ going to suggest a mechanical problem with the woofer or midrange,
but the OP /specifically stated/ that the hissing sound had no relationship
with what was playing, or how loud it was, or /any movement of the cone/.


PeterD

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Jul 21, 2010, 7:34:31 AM7/21/10
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And you've seen electrolitics in cross-overs overheating and hissing?
I'm with Phil on this one...

Meat Plow

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Jul 21, 2010, 9:32:16 AM7/21/10
to

Can't say I've heard an x-over cap his but I've seen them over heat as
evidenced by broken and distored shrink wrap covering .

Amanda Ripanykhazov

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Jul 21, 2010, 12:26:19 PM7/21/10
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I dont know why but the first thing I tried was pushing the cone in to
see if I could identify that rasping effect when a speaker has blown.
Dont know why I did this as the speaker has obviously not blown (the
bass is still quite good. And for some reason I have never
understood, the surrounds in those old speakers aren't made of rubber
which disintegrates so that isnt a problem) in that way but what I
didnt try was to push eccentrically and see if there was any
resistance.

I suspect I am going to have to get them over to Miller Sound at some
time to rebuild (along with a pair of AR3s I have which have badly
corroded cross-overs) but what I was wondering was whether this sound
was likely to make the speaker terminal.

Incidentally the snake behind the woofer is the best description of
what I can actually hear! (a snake with a volume control, that is)

Arfa Daily

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Jul 21, 2010, 2:05:09 PM7/21/10
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"PeterD" <pet...@hipson.net> wrote in message
news:1pmd4697b29f0tobe...@4ax.com...

For once, so am I, although oddly enough, just today I had a non-polarised
electro in the crossover of a JVC home cinema speaker, that had bulged so
badly that it had split open. I suppose that when the can actually ruptured,
it might have hissed for a few microseconds ... :-)

Arfa

Phil Allison

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Jul 21, 2010, 10:15:56 PM7/21/10
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"Amanda Ripanykhazov"


And for some reason I have never
understood, the surrounds in those old speakers aren't made of rubber
which disintegrates so that isnt a problem

** The AR11 woofer has a FOAM surround - all foam surrounds disintegrate
after about 10 to 20 years.

Most woofers made these days use rubber (aka roll) surrounds which have an
indefinite life excepting the odd case of adhesive failure.

.... Phil

bz

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Jul 24, 2010, 7:21:25 AM7/24/10
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I know it is a silly question, but are you SURE that the hiss isn't
coming out of your amplifier?
(have you put a scope on the speaker lines or substituted either speaker
or amp?)

From your description, it isn't clear to me that you have eliminated the
'more obvious' possibility that your amplifier is putting out white
noise, perhaps intermittently varying in amplitude.

Amanda Ripanykhazov

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Jul 25, 2010, 9:09:06 PM7/25/10
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> noise, perhaps intermittently varying in amplitude.- Hide quoted text -
>
> - Show quoted text -

Yeah, switching one speaker pretty much solved that one.

Arfa Daily

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Jul 26, 2010, 4:11:56 AM7/26/10
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"Amanda Ripanykhazov" <dmanz...@googlemail.com> wrote in message
news:8f36b444-2b05-4f98...@g19g2000yqc.googlegroups.com...

What, solved it as in proved that the amplifier *was* the cause, or solved
it as in it wasn't ?

Arfa

Amanda Ripanykhazov

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Jul 29, 2010, 8:25:02 AM7/29/10
to
On Jul 26, 4:11 am, "Arfa Daily" <arfa.da...@ntlworld.com> wrote:
> "Amanda Ripanykhazov" <dmanzal...@googlemail.com> wrote in message
> Arfa- Hide quoted text -

>
> - Show quoted text -

When I took out the speaker and put in another one, the hissing sound
stopped? When I put the speaker in again, the hissing sound started
again

Arfa Daily

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Jul 29, 2010, 12:35:51 PM7/29/10
to

"Amanda Ripanykhazov" <dmanz...@googlemail.com> wrote in message

news:7b33e37c-d03a-4938...@5g2000yqz.googlegroups.com...

I don't suppose that you are just comparing apples and oranges here, are you
? All amplifiers hiss to some degree - generally, although not always,
semiconductor ones more so than tube ones. It's not unusual for one channel
to be a little noisier than the other, so you might hear it more on one side
than the other. If you swap a different speaker onto the hissy channel, the
one that you are swapping in, might not have as good a frequency response as
the one you are taking off, so you might not hear the hiss, and think that
you've cured a problem that's not really there in the first place. I guess
you could also have a defective tweeter or crossover in the speaker that you
*think* is good, because it doesn't hiss, when in fact it is actually bad,
because it's not managing to reproduce the hiss that is a characteristic of
the amp, whereas the other one that you think is bad *is* reproducing it.

If you see what I mean ...

Can you hear hiss in headphones plugged into it ? If so, is it equal between
channels. Does it change depending on what input you have selected on the
amp ? Have you tried swapping the speakers that are always connected to the
system, between channels, rather than swapping in different speakers of
possibly unknown condition and specification. One thing at a time, is the
way forward with this sort of 'problem'

Arfa

GregS

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Jul 29, 2010, 12:43:10 PM7/29/10
to
In article <7b33e37c-d03a-4938...@5g2000yqz.googlegroups.com>, Amanda Ripanykhazov <dmanz...@googlemail.com> wrote:

>On Jul 26, 4:11=A0am, "Arfa Daily" <arfa.da...@ntlworld.com> wrote:
>> "Amanda Ripanykhazov" <dmanzal...@googlemail.com> wrote in message
>>
>> news:8f36b444-2b05-4f98...@g19g2000yqc.googlegroups.com...
>>
>>
>>
>>
>>
>> > On Jul 24, 7:21 am, bz <WQAHBGMXS...@spammotel.com> wrote:
>> >> Amanda Ripanykhazov wrote:
>> >> > Anyone know what this means? This hissing sound isnt constant, it is
>> >> > irregular: =A0It isnt related to the music or any movement of the co=
>ne
>> >> > or any signal put through it, though it doesnt happen when no sound =

>is
>> >> > put through the speaker.
>>
>> >> > Frankly it sounds more mechancial than electronic (as if there is
>> >> > something behind there!) but as I say, it isnt related to whatever i=

>s
>> >> > coming through the speaker though it does increase and decrease with
>> >> > adjustment of the volume control. =A0Andit is louder than most signa=

>ls
>> >> > put through the woofer itself??
>>
>> >> > Is it indicative of some pot in the crossover needing cleaning or is
>> >> > there something else going on please? (I have seen reference to peop=

>le
>> >> > improving the sound of AR11s by bypassing the tone controls in the
>> >> > speaker completely). =A0This speaker is quite elderly and I would
>> >> > imagine that if it does use mechanical pots, they must be fairly dir=

>ty
>> >> > by now
>>
>> >> I know it is a silly question, but are you SURE that the hiss isn't
>> >> coming out of your amplifier?
>> >> (have you put a scope on the speaker lines or substituted either speak=
>er
>> >> or amp?)
>>
>> >> =A0From your description, it isn't clear to me that you have eliminate=

>d the
>> >> 'more obvious' possibility that your amplifier is putting out white
>> >> noise, perhaps intermittently varying in amplitude.- Hide quoted text =

>-
>>
>> >> - Show quoted text -
>>
>> > Yeah, switching one speaker pretty much solved that one.
>>
>> What, solved it as in proved that the amplifier *was* the cause, or solve=

>d
>> it as in it wasn't ?
>>
>> Arfa- Hide quoted text -
>>
>> - Show quoted text -
>
>When I took out the speaker and put in another one, the hissing sound
>stopped? When I put the speaker in again, the hissing sound started
>again

I don't know if my question was ever answered. Where is the hissing
comming from ? Behind speakers means behind the box.

If you can't tell from listening, use a piece of tubing to get location.
You can get it down to less than an inch.

greg

Amanda Ripanykhazov

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Jul 29, 2010, 10:39:16 PM7/29/10
to
On Jul 29, 12:43 pm, zekfr...@zekfrivolous.com (GregS) wrote:
> greg- Hide quoted text -

>
> - Show quoted text -

I thought I made this point in the second posting by saying what I did
to try to trace it by pushing in the woofer (you cant push in a
tweeter that easily), the sound is coming from behind the woofer.

Arfa Daily

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Jul 30, 2010, 4:05:54 AM7/30/10
to

"Amanda Ripanykhazov" <dmanz...@googlemail.com> wrote in message

news:c1be9778-423f-4f2f...@j9g2000yqn.googlegroups.com...

I'm thinking now that this is a windup. Looking at the the account that this
has come from.

dmanzaluni ?

Yes, I think that's maybe true ...

Arfa

Meat Plow

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Jul 30, 2010, 10:18:03 AM7/30/10
to
On Fri, 30 Jul 2010 09:05:54 +0100, Arfa Daily wrote:

>> I thought I made this point in the second posting by saying what I did
>> to try to trace it by pushing in the woofer (you cant push in a tweeter
>> that easily), the sound is coming from behind the woofer.
>
> I'm thinking now that this is a windup. Looking at the the account that
> this has come from.
>
> dmanzaluni ?
>
> Yes, I think that's maybe true ...
>
> Arfa

My reply to the original post was something like "check to see if there
is a snake behind the speaker."

William Sommerwerck

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Jul 30, 2010, 10:29:02 AM7/30/10
to
> My reply to the original post was something like
> "check to see if there is a snake behind the speaker."

I will sometimes reject as a troll a posting that everyone else accepts,
simply because it doesn't "ring true".

Most people do such a bad job of describing what's going on, that a
perfectly legitimate (though odd) situation can come out sounding quite
phony.

I'm starting to think this is a fake.


Meat Plow

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Jul 30, 2010, 4:53:27 PM7/30/10
to

I knew it from the start. It's in my blood :)

Amanda Ripanykhazov

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Jul 30, 2010, 5:03:39 PM7/30/10
to
Thank you for your confidence everyone: If I wanted to wind everyone
up, dont you think I would have found a funnier way of doing it than
this?

If someone can get me a way of posting a wav file to a NG, let me know
and I will stick a microphone in front of the speaker and post
whatever it records

Meanwhile I will take the speaker out and report back if/when I have a
result

Meat Plow

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Jul 30, 2010, 5:41:15 PM7/30/10
to
On Fri, 30 Jul 2010 14:03:39 -0700, Amanda Ripanykhazov wrote:

> Thank you for your confidence everyone: If I wanted to wind everyone up,
> dont you think I would have found a funnier way of doing it than this?

Not if you're just not too funny in the first place.


> If someone can get me a way of posting a wav file to a NG, let me know
> and I will stick a microphone in front of the speaker and post whatever
> it records
>
> Meanwhile I will take the speaker out and report back if/when I have a
> result

But you've already subbed the speaker and the hiss went away or so I
thought I had previously read.

William Sommerwerck

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Jul 30, 2010, 5:59:41 PM7/30/10
to
> Thank you for your confidence everyone: If I wanted to wind
> everyone up, dont you think I would have found a funnier way
> of doing it than this?

You'd be amazed at some of the stupid stuff you see in UseNet groups. I've
never seen any of these that were actually funny.

The problem is that you are describing something that doesn't seem to make
any sense, or have any obvious explanation. This quite naturally makes
people suspicious.


William Sommerwerck

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Jul 30, 2010, 6:01:33 PM7/30/10
to
>> Meanwhile I will take the speaker out and report back
>> if/when I have a result

> But you've already subbed the speaker and the hiss went
> away or so I thought I had previously read.

And no one here is aware of a "mechanism" that causes speakers to produce
hissing sounds on their own, especially when you say the sound is not
related to the program material or its volume.


Meat Plow

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Jul 30, 2010, 7:09:53 PM7/30/10
to

Especially if it is just a passive enclosure. Now a woofer with a built
in amp is an entirely different story.

Arfa Daily

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Jul 30, 2010, 8:35:56 PM7/30/10
to

"William Sommerwerck" <grizzle...@comcast.net> wrote in message
news:i2vi0a$pf1$1...@news.eternal-september.org...

Also, the source sounds suspicious, you must admit ? I mean, dmanzaluni ?
That must be "the man's a loony", mustn't it ? And the nic. Ripanykhazov.
"Rippin' ya clothes off" maybe ?

Dunno. Sorry if I'm being unfair to you, but the more I look at this, the
more it doesn't make any sense, and the more it begins to look like a usenet
windup ...

Arfa

William Sommerwerck

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Jul 30, 2010, 9:25:44 PM7/30/10
to
> Dunno. Sorry if I'm being unfair to you, but the more I look
> at this, the more it doesn't make any sense, and the more
> it begins to look like a usenet windup ...

Of course, if it is true, we might read the following in the newspaper...


Woman killed by poisonous snake

Miss so-and-so was killed yesterday when bitten by a viper hiding behind one
of her loudspeakers. The animal had curled up there for warmth, and had
attracted her attention by making random hissing noises when music was
played.


Ron

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Jul 31, 2010, 7:43:39 AM7/31/10
to
On 31/07/2010 01:35, Arfa Daily wrote:

> Also, the source sounds suspicious, you must admit ? I mean, dmanzaluni
> ? That must be "the man's a loony", mustn't it ? And the nic.
> Ripanykhazov. "Rippin' ya clothes off" maybe ?

Rip her knickers off, Shirley ;)
--
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Amanda Ripanykhazov

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Jul 31, 2010, 11:04:14 AM7/31/10
to

Call me an old cynic and obviously I am not a technical expert but
doesnt simple logic mandate that when you sub a speaker and the sound
goes away, all it means is that (what I thought blindingly obvious
from the symptoms and there being no apparent logical connection
between the source and the hissing, which was why I posted here:
Because "The problem is that you are describing something that doesn't
seem to make any sense, or have any obvious explanation" so I wondered
whether anyone had come across it before) the sound wasnt coming from
the source? Or did I have to add that when i put the speaker back
again, the sound came back?

William Sommerwerck

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Jul 31, 2010, 12:30:44 PM7/31/10
to
Call me an old cynic and obviously I am not a technical expert but
doesnt simple logic mandate that when you sub a speaker and the
sound goes away, all it means is that (what I thought blindingly obvious
from the symptoms and there being no apparent logical connection
between the source and the hissing, which was why I posted here:
Because "The problem is that you are describing something that doesn't
seem to make any sense, or have any obvious explanation" so I wondered
whether anyone had come across it before) the sound wasnt coming from
the source? Or did I have to add that when i put the speaker back
again, the sound came back?

Your speakers are passive devices. They cannot make any sort of sound on
their own.

If hissing is coming from one of them (but not the other, when driven from
the same amp), the speaker must be therefore be the source of the hiss. But
as there is nothing in the speaker that could, by itself, create sound, then
the speaker must be altering or distorting its input to produce the hiss.
However, you say that the presence or level of the hiss is not related to
the program material.

This makes no sense. The logical conclusion is that A: you are grossly
mis-describing the symptoms, or B: this is a troll.

I think it's B. I really don't have any more time for this tsuris/tsimmes.
Take your pick.


Jamie

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Jul 31, 2010, 1:45:47 PM7/31/10
to
Amanda Ripanykhazov wrote:

check for electrical devices adjacent to the speaker, inside and outside
of the wall. Your speaker coil maybe in the path of an induced magnetic
field from a device near by..

etc..


nesesu

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Jul 31, 2010, 3:25:38 PM7/31/10
to
On Jul 31, 9:30 am, "William Sommerwerck" <grizzledgee...@comcast.net>
wrote:

There is a slight possibility that there is an issue with the
crossover in this speaker that de-stabilizes the driving amplifier,
causing an HF oscillation in the amp, yet the amp IS stable with the
other speaker.
I worked on an Pioneer amp that was marginally stable and would
oscillate depending on the load. The clue it was oscillating was a
'sizzle' in the speaker and the overload lamp was always lit. Other
than that it appeared to work fine to the owners old ears, although
there was a slightly perceptable clipping distortion on louder
passages. A slight adjustment of the R-C feedback in the amp returned
the rock solid stability and eliminated the perceived 'hiss'.
That system had been to two 'professional' shops; one said there was
nothing wrong and the other said it could not be repaired.

Neil S.

Arfa Daily

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Jul 31, 2010, 9:42:17 PM7/31/10
to

"Ron" <r...@lunevalleyaudio.com> wrote in message
news:jKydnVWRZZH1kcnR...@bt.com...


> On 31/07/2010 01:35, Arfa Daily wrote:
>
>> Also, the source sounds suspicious, you must admit ? I mean, dmanzaluni
>> ? That must be "the man's a loony", mustn't it ? And the nic.
>> Ripanykhazov. "Rippin' ya clothes off" maybe ?
>
> Rip her knickers off, Shirley ;)
> --


Ah yes, Ron ! Well spotted ... :-)

Arfa

Meat Plow

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Aug 1, 2010, 6:11:10 PM8/1/10
to

Sorry if you have been labeled a troll. You seem to have enough sense to
effect a repair so please do.

Meat Plow

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Aug 1, 2010, 6:14:15 PM8/1/10
to

I wouldn't bet on it and I'm not going back through the thread because I
don't thread or keep or watch articles but, I thought Amanda said the
speaker hissed on its own without an amp powered up.

William Sommerwerck

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Aug 1, 2010, 6:45:07 PM8/1/10
to
> Sorry if you have been labeled a troll. You seem to have
> enough sense to effect a repair so please do.

If you do effect a repair, please let us know what the problem was. I would
be delighted to learn that I was wrong.


William Sommerwerck

unread,
Aug 1, 2010, 6:46:41 PM8/1/10
to
> I wouldn't bet on it and I'm not going back through
> the thread because I don't thread or keep or watch
> articles but, I thought Amanda said the speaker
> hissed on its own without an amp powered up.

My memory is that she said it didn't -- the amp had to be on. But there
seemed to be no correlation between the program's content or volume.

Put a 'scope on the amp's output, if you can.


Michael A. Terrell

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Aug 2, 2010, 9:01:11 AM8/2/10
to


1: Google doesn't allow any attachments.

2: This is not a binaries newsgroup so any message with an attachment
won't propagate to most news servers.

Michael A. Terrell

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Aug 2, 2010, 9:03:30 AM8/2/10
to


You think she has a MRI machine in her wall? The voice coil isn't
going to be affected by nearby magnetic fields, due to the narrow gap
and shielding.

GregS

unread,
Aug 2, 2010, 10:05:26 AM8/2/10
to
In article <cc42fb59-8483-4e9e...@q35g2000yqn.googlegroups.com>, Amanda Ripanykhazov <dmanz...@googlemail.com> wrote:
>Thank you for your confidence everyone: If I wanted to wind everyone
>up, dont you think I would have found a funnier way of doing it than
>this?
>
>If someone can get me a way of posting a wav file to a NG, let me know
>and I will stick a microphone in front of the speaker and post
>whatever it records


I thought it was from BEHIND the speaker.

!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Chuck

unread,
Aug 2, 2010, 10:21:24 AM8/2/10
to
On Tue, 20 Jul 2010 12:30:48 -0700 (PDT), Amanda Ripanykhazov
<dmanz...@googlemail.com> wrote:

>Anyone know what this means? This hissing sound isnt constant, it is

>irregular: It isnt related to the music or any movement of the cone
>or any signal put through it, though it doesnt happen when no sound is


>put through the speaker.
>
>Frankly it sounds more mechancial than electronic (as if there is

>something behind there!) but as I say, it isnt related to whatever is


>coming through the speaker though it does increase and decrease with

>adjustment of the volume control. Andit is louder than most signals


>put through the woofer itself??
>
>Is it indicative of some pot in the crossover needing cleaning or is

>there something else going on please? (I have seen reference to people


>improving the sound of AR11s by bypassing the tone controls in the

>speaker completely). This speaker is quite elderly and I would
>imagine that if it does use mechanical pots, they must be fairly dirty
>by now


I once lived in an old mansion that had been converted into an
apartment building where one of my KLH 32 speakers was mounted by the
main electrical entrance for the building. There sometimes was a soft
noise from the tweeter without the amplifier being on. Later on we
discovered that the owner of the building had replaced one of the
cartridge fuses in series with the hot 120 AC in with a piece of
copper pipe that was arcing at the fuse clips. I know this sounds
apocryphal but I spent 32 years in the consumer audio field as a
technician, and service and store manager so you can be reasonably
sure, in this case, that I'm not a troll . Chuck

William Sommerwerck

unread,
Aug 2, 2010, 10:28:20 AM8/2/10
to
> I once lived in an old mansion that had been converted into an
> apartment building where one of my KLH 32 speakers was mounted
> by the main electrical entrance for the building. There was sometimes

> a soft noise from the tweeter without the amplifier being on. Later on
> we discovered that the owner of the building had replaced one of
> the cartridge fuses in series with the hot 120 AC in with a piece of
> copper pipe that was arcing at the fuse clips.

What do you think formed the "return path" that allowed current to flow
through the speaker?

For example... In the simplest possible 2-way system, with only a capacitor
in series with the tweeter, * there would be no complete circuit for the
current to flow through the tweeter, unless the unpowered amplifier had a
sufficiently low output impedance.

* The woofer can be designed to mechanically roll off at the crossover
frequency, so no inductor is needed.


nesesu

unread,
Aug 2, 2010, 11:19:30 AM8/2/10
to
On Aug 2, 7:28 am, "William Sommerwerck" <grizzledgee...@comcast.net>
wrote:

The tweeter, capacitor and woofer are all effectively in series as a
loop in the speaker box, and that loop is large enough to pick up the
high M field spectrum of the arcing 60Hz so close by. Some of that
generated arc noise will fall in the band that the tweeter will
reproduce efficiently.

Neil S.

Meat Plow

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Aug 2, 2010, 12:02:39 PM8/2/10
to

An old friend used to live within a hundred feet of a radio station. He
swears that on one occasion he could hear programming coming from a
filling in one of his molars.

William Sommerwerck

unread,
Aug 2, 2010, 12:27:25 PM8/2/10
to
> The tweeter, capacitor and woofer are all effectively
> in series as a loop in the speaker box...

Duh. I should surrender my BSEE.


Arfa Daily

unread,
Aug 2, 2010, 8:18:22 PM8/2/10
to

"Meat Plow" <mhy...@yahoo.com> wrote in message
news:pan.2010.08...@hahahahahahahah.nutz...

This is quite common. The BBC used to operated a long wave transmitter in
the county where I live. It was 200kW during the daylight hours, and 470kW
at night. There were always reports in the local newspaper of people
experiencing oddball reception events, and picking up radio 'in your head'
was a regular one. Apparently, it happens more when fillings are new, and
the oxide layers or what have you, are still building. Supposedly, the
filling acts as a simple diode detector, and if the field strength is high
enough, actually 'rattles' mechanically. The vibration from this passes out
of the tooth and up the jawbone into the skull, where it is picked up
directly by the ears. I have also seen the phenomenon explained as the
detected audio voltage passing out of the tooth, and directly stimulating
nerves that are part of the hearing centre. I suppose that's possible, but
it sounds less likely to me, than the first explanation.

Another few favourites for 'ghost' reception near this transmitter, were
electric cookers, stereo systems that were turned off, and mattress springs
!!

Arfa

Meat Plow

unread,
Aug 3, 2010, 8:37:32 PM8/3/10
to


So Amanda may live near a 500kw transmitter that plays wildlife sounds.
That would explain the snake hissing behind her speaker.


--
This is a test sig

Michael A. Terrell

unread,
Aug 3, 2010, 11:34:59 PM8/3/10
to

WLW in Cincinnati, Ohio used to run 500 KW on 700 KHz under an
experimental license. Local farmers reported talking and singing fence
wire or a few miles from their tower.

http://hawkins.pair.com/wlw.shtml has some photos and a description,
along with a simplified schematic of the beast. It also has one of the
few remaining Blaw-Knox diamond towers.

WSM in Nashville has another Blaw-Knox tower. http://www.wsmonline.com

Ron

unread,
Aug 4, 2010, 6:06:14 AM8/4/10
to

In the house where we lived some years ago, we used to get 'fax machine'
noises from the bedside lamp during the night. Happily it only happened
when it was switched on.

Ron(UK)

Meat Plow

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Aug 4, 2010, 8:16:08 AM8/4/10
to

William Sommerwerck

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Aug 4, 2010, 8:41:45 AM8/4/10
to
> This is quite common. The BBC used to operate a long wave

> transmitter in the county where I live. It was 200kW during the
> daylight hours, 470kW at night. There were always reports in

> the local newspaper of people experiencing oddball reception
> events; picking up radio "in your head" was a regular one.

Did they hear it when they weren't relieving themselves?

"Mythbusters" did a segment on this, referencing a claim by Lucille Ball of
having heard radio signals in her head during the '40s. Adam and Jamie did
an uncharacteristically shallow investigation, and were unable to confirm
the effect.


Arfa Daily

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Aug 4, 2010, 12:41:36 PM8/4/10
to

"William Sommerwerck" <grizzle...@comcast.net> wrote in message
news:i3bn7r$ip0$1...@news.eternal-september.org...

Whilst it's undoubtedly an entertaining show to watch, I do sometimes find
the science to be a little 'questionable', probably because of a need to
ensure entertainment value for the network. At the end of the day, almost
anything will work as a simple diode detector, and I see no reason why that
shouldn't be true of an amalgam tooth filling, which is a fairly complex
layered structure, sitting in a conductive liquid. To be fair, I'm pretty
sure that when I first looked into this effect many years ago, whatever I
was reading suggested that it was particularly related to 'new' fillings.
This may well be the case, as new fillings have that very metallic taste
that is actually, I understand, them acting as a tiny battery, and giving
the tongue a mild electric shock, which the brain translates as a 'taste' as
the nerves are being stimulated directly. 470kW of AM must result in a
mother of a high field strength in the locality.

Arfa

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