PSW505 Subwoofer - Amp Circuit Board Diagram?

Eddy_Kemp

Happy July everyone!

I struck out calling Polk tech support so I'm hoping a fellow forum lurker or Polk customer service rep can help me out.

My ~6yr old PSW505 subwoofer recently died after what started as crackling feedback coming out of standby mode, culminating in the dreaded "heartbeat" and no longer powering on.

Now, I'm looking for the amp circuit board diagram in an effort to identify and replace what appear to be fried resistors(?) - see pics below.





Any help or direction would be much appreciated!

Clipdat

Not to rain on your parade, but if I were you I would save myself the headache of trying to repair it, and instead spend my time and money on obtaining a quality subwoofer from SVS, Rythmik, REL, Velodyne, etc.

choco___

So it looks like they used to give them out: https://forum.polkaudio.com/discussion/176902/psw505-light-on-rear-not-switching-from-red-to-green#latest

And I've been going back in forth with a support ticket I have open with their Customer Care Team, this was their response:

"We apologize to inform you that we do not have the information that you requested. Such information is only accessible by our technicians at our repair facility and we do not have any means of getting it from them."

Polk Audio has contradicted themselves twice now, for me at least. I don't know what their deal is...

icerdb

Hi, I've had 3, yes 3 PSW505 subs, and all have stopped switching out of standby and when they do, sound like ****. Doesn't sound like Polk wants to help anyone. I was unable to fix the 1st just-out-of-warranty sub because the circuit board was badly head damaged, and couldn't solder in new components. I junked it. Now the other 2 intermittently do not come out of standby, and when they do, they are quiet, and distorted badly.

These amps have problems at the design level that Polk should be addressing, and they should be able to replace or repair these amps. Has ANYONE "called Polk's CS at: 1-800-377-7655 and selected option 1" AND gotten their amp fixed or replaced?? They are most definitely are not in the business of releasing schematics to the public even though these amps all fail from design or component related problems from the factory. They should be sued and do like Ford and their airbags and have a mass recall on the amps, but who's going to make any money doing that? Certainly not Polk.

I'm an electrical engineer and know what's wrong with my amps. I'm willing to give repair information to anyone who wants to fix their own amps. I know all the component values, and as long as the circuit board soldering pads aren't badly burned up, if you can un-solder and re-solder components, you can fix yourself.

I'm contacting Polk about my only in-warranty sub, and if they won't help, I'm going to probably purchase replacement amps instead of attemptting repairs again that will only fix the problem until it arises again.

SeleniumFalcon

I'll forward your post to a friend at Polk, he probably won't be able to contact you until Monday. Hang in there he'll help.

Eddy_Kemp

Really appreciate the replies icerdb and SeleniumFalcon!

Funny how the universe works... running a garage sale today and the same busted sub I posted about last year was going to be junked as part of the larger declutter effort.

Then, suddenly, replies on my old post!

I'll watch for contact from you friend, icerdb, and will definitely follow up with questions - assuming I can get a diagram - to SeleniumFalcon. I'm a tech-savvy IT guy, but definitely outside my normal projects with a repair job like this.

Thanks again all!

Rumen

In the same boat like everyone else. Did anyone actually got a schematic or completed a successful repair?
My 505 was flashing red, and now completely refuses to power on at all.

Eddy_Kemp

Hi Rumen,

No schematic or follow up yet from Polk. If I hear anything outside this thread I will definitely reply back.

SeleniumFalcon

It would be best to send an email to: Kim.Jasper@soundunited.com and explain the circumstances.

Eddy_Kemp

Success!

Kim Jasper - per SeleniumFalcon's suggestion - delivered the goods.

SeleniumFalcon

That's good news!

skrol

I picked up a PSW110 cheap with a blown amp. I bought a plate amp from Parts Express to replace the failed amp and it was a nice upgrade. It did take a little modification to physically fit in the 110 cabinet.

dudaindc

Kim Jasper provided stellar customer support regarding my faulty PSW505.
Kudos to him!

dudaindc

SeleniumFalcon wrote: »

It would be best to send an email to: Kim.Jasper@soundunited.com and explain the circumstances.

Thanks for the recommendation - it work like a charm for my issue.

Old_school70

Folks - I realize this is an old post, but I have the same issue as you guys. PSW 505, amplifier failure. I am a retired EE.

My sub is exhibiting cyclic noise (mid level screeching)…..silence…… screeching. It was originally bought in 2014, and plate amplifier was replaced in 2020, by Polk under a “good will” warranty claim.

I was on the horn yesterday with Polk tech support, and they may be willing to replace it, but will be a few days to hear back.

Since this is a common failure (many many customers have dealt with it), has anyone determined the root cause. My assessment is this is a likely a heat related issue as it seems that the amp fails after 4-6 years, and is fundamentally a design issue. In my home theater, I have always kept it powered on, and set the standby switch to operate. We have a whole house surge protector in place.

One YouTube video indicated that all the capacitors should be changed. This is a PITA, but doable in my shop.

If Polk offers a replacement free of charge, I may opt to replace it, though I’d rather not have to deal with it ever again. Has Polk redesigned it or are they shipping the same design?

Is there a recommendation for a COTS replacement from another mfr?

Cheers