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Old 12th October 2010, 04:03 AM   #331
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Hello All. I'm looking for fried PB12's to buy, as long as the driver is still in good condition. I fried my PB12 4 years ago, and I have revived it and I'd like to add some more to my room. Anyone have PB12's for sale?!

Thanks!!
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Old 1st November 2010, 08:58 PM   #332
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my subwoofer is in great shape and the box is solid but with some scratches on them, the poweramp is fried and gone. If you are near Norfolk,Va or within 200 miles; we might arrange something: my email is timehascome444@Yahoo.com but after Thanksgiving it's going on Craigslist. let me know and I'll send a picture....
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Old 30th January 2012, 01:00 AM   #333
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Hey everybody! New here. I too have fallen prey to the PB12 dilemma! Except, I bought mine, brand new over 10 years ago and never once had a problem with it.
It went out yesterday and with a bit of searching I found this site. I read the entire post and then noticed that it started way back! lol.

So, to my dismay I guess it's buy a new amp or new unit, I'm sad.
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Old 4th April 2012, 08:36 PM   #334
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Quote:
Originally Posted by roberts5008 View Post
Hey everybody! New here. I too have fallen prey to the PB12 dilemma! Except, I bought mine, brand new over 10 years ago and never once had a problem with it.
It went out yesterday and with a bit of searching I found this site. I read the entire post and then noticed that it started way back! lol.

So, to my dismay I guess it's buy a new amp or new unit, I'm sad.
i have an early model of the PB12 (made in canada) before they switched to a Mexican-made version. It has performed well for 11 years. Lately it pops and groans when turned on and it crackles and doesn't play well. I left it off for 2 months and decided to turn it on again today. After initially popping and groaning it is now playing close to normal (i think). After reading all the horror stories about the burnt power module, i am wondering if i should leave this alone or take it apart and see the condition of the board. Thoughts?
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Old 19th May 2013, 10:24 PM   #335
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i have been able to repair mine S53AMI it need cautions and its back on-line,i could tech u

Last edited by gozo; 19th May 2013 at 10:26 PM.
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Old 14th January 2014, 03:00 PM   #336
EsoBOFH is offline EsoBOFH  Canada
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Wow... What a great thread with amazing knowledge and input by all!

Mid-thread, I was very hopeful that the uber technical among us had come up with a good solution and found a way forward with these subs/amps, but by the end it turned into an amplifier swap-out party, which makes me sad, but sounds like it may be the reality with this unit.

So, why am I chiming in? I too have a pb12 and, despite all the issues surrounding it, quite enjoy the sound and performance (largely due to what came before it for me, don't get me wrong, I know there are lots better subs out there). Having said that, mine has just started exhibiting some weirdness... Around 50% of the time, when its kicking in, it makes a strained squak/groan but then performs fine. I've also once noticed it go into standbye when I paused a movie briefly - with no 15 minute time out period. It had been playing fine before I paused it, and it continued fine when I resumed the movie. Odd.

Anyway, the later issue seems a one-off, more of a side note to the larger issue.

I enjoyed the thread immensely, but admittedly, didn't understand a whole lot of it. I'm wondering, can someone sum up a reasonable approach to extending the life of this unit? Some prescription for palliative care?

What would be the most effective upgrade to perform? Can someone suggest a list of the most likely components I should replace to keep my unit going strong?

I have a revision 2 unit.

Thanks to any technical guys/gals that can chime in!
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Old 14th January 2014, 05:55 PM   #337
PsychoM is offline PsychoM  Belgium
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I have a JBL Digital 12 that's roughly based on a similar S53 module.
I have found that the large power resistors (the largest resistors on the board) are way too close to the PCB. They get too hot and the PCB will 'burn' very slowly.
I saw this while doing a routine check-up and I had to hard-wire the PCB traces because they were damaged so badly...
This thing HAD to break, it wouldn't have survived another year. I'm so sad that this has to be a JBL product, considered a 'quality' brand.
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Old 14th January 2014, 06:00 PM   #338
EsoBOFH is offline EsoBOFH  Canada
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Quote:
Originally Posted by PsychoM View Post
I have found that the large power resistors (the largest resistors on the board) are way too close to the PCB. They get too hot and the PCB will 'burn' very slowly.
Had you noticed any issues prior to that? Are you still going strong having replaced those resistors now?
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Old 14th January 2014, 08:07 PM   #339
PsychoM is offline PsychoM  Belgium
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Originally Posted by EsoBOFH View Post
Had you noticed any issues prior to that? Are you still going strong having replaced those resistors now?
I have bought the sub second hand. It worked good. I know the former owner never abused it, but I decided to check it anyway and that's when I found this out. So I don't know if there were any issues before I got it.
I do know the board was still stock, nothing was replaced or modded.

It's still going strong (about 6 months ago I replaced the resistors).
But it won't last forever this way. The PCB was burnt so badly I should have cut the burned pieces out and fill them with epoxy or something like that and redraw the traces. Unfortunately this was a 2-layer board and I don't have the skills to do that...
So I replaced the resistors with much larger ones and I kept them away from the PCB using spacers/straws.
Sooner or later, it's going to fail again.

It's not difficult to check if your board has similar problems: look for black areas on the pcb, like this. If the traces are already coming loose from the board, the damage is severe.

Last edited by PsychoM; 14th January 2014 at 08:13 PM.
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Old 14th January 2014, 08:41 PM   #340
EsoBOFH is offline EsoBOFH  Canada
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Quote:
Originally Posted by PsychoM View Post
So I replaced the resistors with much larger ones and I kept them away from the PCB using spacers/straws.
Sooner or later, it's going to fail again.
When you say, it's going to fail again, do you mean it had failed outright before, or you just mean, it will get hot/burn again? was it at any point not working before you decided to replace the resistors?

You said you put much larger ones in - larger ones of the same value, or ones with a higher resistance?

thx.
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