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pyonc
11-06-2011, 06:08 PM
Hi,

I need your advice on how to get rid of bass noise from 4343.
I listen to them in a biamp mode. No issue with the mid-range or hig-range sound. everytime when I turn up or down the volumn for the bass,
I hear this little noise from the right bass, but nothing from the left.:confused:
I don't hear any noise from the right bass when playng music.
Only when I wiggle the volume control for the right bass.
What is the possible cause of this noise? And any quick fix?
Thanks for your reply in advance.

BMWCCA
11-06-2011, 08:15 PM
When you say "volume control" are you talking about the L-pad?

Robh3606
11-07-2011, 08:24 AM
Check the individual driver level controls in the active crossover. I had the same noise issue in one of my 2123's in my active set-up and it was a level control that had become oxidized. I just ran it through it's range and that cleared it up. What crossover are you using?? Are you talking the amp level control for that channel?? Could be that has oxidized as well couldn't hurt to turn it off and rotate it a couple of times.

Rob:)

Hey19
11-07-2011, 01:26 PM
When you say "volume control" are you talking about the L-pad?
You're a funny old man with your question.:lol_fit:

pyonc
11-07-2011, 02:35 PM
When you say "volume control" are you talking about the L-pad?

No, it's volumn button on the Crown amp, namely amp volume contro. There're two volume channels on the front, namely one each for left and right speakers. Initially I thought the noise was coming from the mid-range drivers, so I wiggled the L-pad control buttoms several times, but upon closer listening, the noise was coming from the low-frequency driver on the right speaker when I turned up or down the volumn channel (as I explained aleady).

pyonc
11-07-2011, 02:39 PM
Check the individual driver level controls in the active crossover. I had the same noise issue in one of my 2123's in my active set-up and it was a level control that had become oxidized. I just ran it through it's range and that cleared it up. What crossover are you using?? Are you talking the amp level control for that channel?? Could be that has oxidized as well couldn't hurt to turn it off and rotate it a couple of times.

Rob:)

Yes, it's the amp level control (Crown DC300A).
As you know, this amp has two volumn channels on the front, one each for left and right speakers. And I use the recommeded 300hz for the low frequency, and the active crossover is JBL M552.

BMWCCA
11-07-2011, 05:42 PM
Yes, it's the amp level control (Crown DC300A).
As you know, this amp has two volumn channels on the front, one each for left and right speakers. And I use the recommeded 300hz for the low frequency, and the active crossover is JBL M552.
Actually, the Crown controls are input attenuators. Not really volume controls. If you can control the level relative to the high-frequency amp with your crossover, maybe you could try running the Crown's controls wide-open and see if that helps clear it up. :dont-know:

JeffW
11-07-2011, 06:54 PM
Is this the same amp that you had fry some voice coils not long ago?

pyonc
11-07-2011, 07:15 PM
Is this the same amp that you had fry some voice coils not long ago?

Hi, JeffW,

Thanks for reminding me of the unhappy memories. Yea, that's correct.
But the cause of the fried coils at the time was the vintage untesed Crown VFX-2 active crossover, not the amp itself. Never, ever will try such vintage unless it's been tested fully.

As you know, this Crown DC300a has two level controls on the front. I hear some little yet audible noise coming out from the 2331A low-frequency speaker when I turn the right level control down or up. The left one has no such issue at all, though. Still wondering if it's caused by the amp or the LOW speaker itself. Both low speakers have been reconed with original JBL factory kits recently at a JBL shop, though.

JeffW
11-07-2011, 08:07 PM
The crossover might not have been 100%, but I can't imagine a crossover being able to put out enough DC to cook a voice coil in a woofer.

I'd be trying to beg, borrow, or steal another amp to run on those woofers.

Think about it... Your woofer was making a little noise, then it quit. Voicecoil welded into the gap. You get the woofers rebuilt. Woofer starts making a little noise again. The only constant? The amp. My guess is that you are about to revisit the fried voicecoil portion of the equation.

pyonc
11-08-2011, 08:24 AM
The crossover might not have been 100%, but I can't imagine a crossover being able to put out enough DC to cook a voice coil in a woofer.

I'd be trying to beg, borrow, or steal another amp to run on those woofers.

Think about it... Your woofer was making a little noise, then it quit. Voicecoil welded into the gap. You get the woofers rebuilt. Woofer starts making a little noise again. The only constant? The amp. My guess is that you are about to revisit the fried voicecoil portion of the equation.

Thanks. Will check it with another amp.

JeffW
11-08-2011, 09:31 AM
It might not be as dire as I made it out to be, but you need to have that amp looked at. It could be something as minor as a dirty attenuator pot, but since you've already lost a voicecoil with this amp connected, I'd be very wary of it.

pyonc
11-08-2011, 07:15 PM
It might not be as dire as I made it out to be, but you need to have that amp looked at. It could be something as minor as a dirty attenuator pot, but since you've already lost a voicecoil with this amp connected, I'd be very wary of it.

Well, I've just found I hear the same kind of noise from the left woofer, too, when I wiggled the volume level controle up or down, after swiching the speaker wires reversely. So, I think it the dirty attenuator pot of the Crown amp's right level control. Fortunately I don't hear the noise from both woofers while playing music. Yet, I think I have to buy another amp in the near future. Thanks, JeffW.:applaud:

audiomagnate
11-12-2011, 04:58 PM
Sounds like a job for Deoxit!

Eaulive
11-13-2011, 11:12 AM
Sounds like a job for Deoxit!

Or plain'ole WD40 :applaud: