Crackling driver in polk 5jr

[fro98665]

Hello,

I have a set of polk 5jr's(with radiator) that I just bought for $30. One of the speakers crackles at middle volumes. It is not the tweeter since I disconnected it to make sure. I then have another driver I put it in to make sure, it crackled also.

Do I have two blown MW6502 drivers or could it be something else?

Thanks,

Fro

[gdb]

Have you swapped the drivers over to the other cabinet ? If no crackle , then it's the crossover or something in that cabinet's wiring that's causing your problem. New caps for that model shouldn't cost much $$ and will improve the sound.

[Lasareath]

^^^ What He Said! ^^^

[fro98665]

I found out that it is not the driver. Ran a driver that made the crackling/vibrating noise in a different speaker (a ported 5jr) with no noise.

It's wierd, sounds like a physical problem rather than an electrical one, which only happens with more volume.

This has to have happened to someone else I am sure, just hard to describe in exact words.

Thanks.

[skrol]

Have you checked how well your cabinets are sealed? If the cabinet is not sealed,the MW cone will have longer excursions and possibly bottom-out.

Gently press the PR in and hold. You should see the MW move outward. The pressure slowly bleeds down and the MW will return to its normal resting position. This usually takes a few seconds; the longer the better seal. If the MW does not move or moves back rapidly then your cabinet is not sealed well enough.

My Monitor 5A's hold for about 6 seconds while my RTA11TL's hold for about 4 seconds.

Sources of leakage are: 1) the MW, PR, Tweeter and Terminal cup mounting surfaces, 2) the cabinet corners, 3) the MW dust cap. You can't do anything about the dust cap and this is normal. The cabinet corners can be sealed inside with calk. The mounting surfaces can be sealed with new gaskets or "MoreTite".

Stan

[fro98665]

Thanks Skrol, I believe you hit it on the head.

I tried depressing the PR, the MW goes out and bleeds back in about 1 second.

I will order some new gaskets and seal cabinets from the inside.

Thanks again.

[PreCd]

You can check with brgman to see if he has any gaskets left and if he has that size.

Here is the link to the gasket thread: http://www.polkaudio.com/forums/show...gaskets+brgman