Whistling air out from back of the sub

[buzzlight79]

Hello community,
I got my B&W ASW300 repaired and back yesterday (the transformer was dead, at least it's what I 've been told) but now it is working, as soon as some bass is playing I can hear the sub buzzing and whistling (tth bass sound is definitely not clear and sharp).

When there are lot of bass, I can feel lot of air going out from the rear of the sub (through the RCA jacks and every switch).

I run some calibration tests and manual setup like auto calibration, then manual xover setup, line level adjusting, setting speakers to small, but it is still here.

My receiver is a Pioneer VSX-1014TX-k that I just bought so I thought I simply may not know how to use and set everything yet, but, with my little subwoofer knowledge, it's more a question of ."box hermetism". Could it be something else?
Is there a way I can open the sub and check some things (only if I get instructions cause I don't want to make things worse) ?

Any help is appreciated... maybe I can at least know if it is worth repairing (I bought it used for $100 and got it partly-repaired for $50). I am not sure whether I should get rid of it and buy a new one...

Thanks in advance!

 

[Knucklehead90]

The repair shop has probably left the inside cover off the amp. Amps that do not have sealed controls and switches need a cover to keep the air from rushing in and out with the movement of the driver.

This is gross incompetence on the part of the repair shop.

 

[buzzlight79]

missing cover from a previous maintenance/repair?

The repair shop has probably left the inside cover off the amp. Amps that do not have sealed controls and switches need a cover to keep the air from rushing in and out with the movement of the driver.

This is gross incompetence on the part of the repair shop.

I understand what you mean. And thank you for the hint.

The guy who first repaired it (replacing the dead transformer) is doing it undeclared, so not through a shop (cheaper but riskier, of course).
Besides, since I bought the sub used, maybe this missing cover dates back from a previous repair I am not aware of... indeed, forgetting to replace this cover is truly unprofessionnal...
So I just called back the repair guy and he accepts to come by, at my place, and seal the amplifier box for free. Does it mean he is feeling guilty for something? Or is he just professionnal and want to build a relationship?

Anyways, he told me it is a 10 minutes job, using a special silicone (not using a plastic cover)... It is the way it should be repaired or is it kinda gross repair?

 

[Warpdrv]

Sounds like he's trying to make it right by you by stopping back to your house instead of having to drag the sub out of your house...

Let him make it right and buy him a beer - have a chat - make a friend...

Unless he is a gang member type thing, seems like he's doing the right thing..

 

[Knucklehead90]

If he can get to all the switches plugs and screw holes the silicone sealant should do the job. Also make sure there is a gasket in place between the plate and the sub enclosure. Having a small roll of weather stripping on hand wouldn't hurt just in case.

If this sub didn't have that cover on it before I think you'd have noticed it.

I agree with Warpdrv - have a beer handy - a good (and cheap) repair tech is hard to find. Knowing about air sealing can be forgiven if he hasn't worked on a sub before.

 

[buzzlight79]

Thank you guys for your advices.
I'll have a weather stripping roll, just in case.
By the way, according to what he told me, he has been repairing subs for quite a long time... Should I forgive him for forgetting/omitting to mention this absence of sealing cover? haha just kidding.

We'll have a beer and if he's doing a good job with my sub on saturday, for sure, I'll preserve this precious resource.

I'll let you know how the repair job went.

Cheers

 

[Knucklehead90]

As I mentioned earlier some amps have the cover - some do not. As this is a used amp it may not have had the cover to begin with - but I think you'd have noticed the sub farting. It is a rather distinct sound.

 

[buzzlight79]

Hello guys,
So it's been a while now since my last update on this post.
The repair guy was supposed to come at my place (and then we would have had a beer! but he never came... I tried to call him few times and nothing. So I just gave up on him and decided to get the sub repaired either by myself either through an "official" repair store.

So tonight I opened the plate and I figured out there used to be a cover but it is not here anymore! (there marks of glue forming a square around the electronics and 4 unused screws positioned at the 4 corners around the electronics.
So now I am thinking of finding a way to seal the box. Should I find a proper cover that will fit the plate or can I manually fill in all the screw holes, connectors and switches? Are there any risks doing this?
I am thinking of the speaker plugs : if I fill them with silicone would not they be unusable ? (right now, I don't care because I am using a RCA cable in the line in plug, but if I decide to sell it later...)

Finally, what sealing/grease product should i use when remounting the plate (for the last screws)?

Again, thank you very much for all your advices and opinions.

Olivier

 

[TLS Guy]

Hello guys,
So it's been a while now since my last update on this post.
The repair guy was supposed to come at my place (and then we would have had a beer! but he came... I tried to call him few times and nothing. So I just gave up on him and decided to get the sub repaired either by myself either through an "official" repair store.

So tonight I opened the plate and I figured out there used to be a cover but it is not here anymore! (there marks of glue forming a square around the electronics and 4 unused screws positioned at the 4 corners around the electronics.
So now I am thinking of finding a way to seal the box. Should I find a proper cover that will fit the plate or can I manually fill in all the screw holes, connectors and switches? Are there any risks doing this?
I am thinking of the speaker plugs : if I fill them with silicone would not they be unusable ? (right now, I don't care because I am using a RCA cable in the line in plug, but if I decide to sell it later...)

Finally, what sealing/grease product should i use when remounting the plate (for the last screws)?

Again, thank you very much for all your advices and opinions.

Olivier

I would not put sealant around switches etc. That will do damage.

I would try and get a new cover from B & W. If that fails, if you have the equipment fabricate a new case.

If you are not able to do it, I'm sure you have a local machine and welding shop that could fabricate you one at a reasonable cost.

I would have them fabricate it out of aluminum or sheet metal. have them bend up the case with the flange for the mounting screws and weld up the seams. A heating contractor might also be able to fabricate this for you.

 

[buzzlight79]

Thank you TLSguy for your (incredibly!) fast response.
I contacted a B&W reseller. Maybe the will be able to provide the part.
Otherwise, I'll try the machine and welding shop option.

I keep you posted.