PSW10 blows fuse

[ckp]

Hello,
First time poster. I have a PSW10 that is not functioning and blowing the fuse. Upon further visual inspection I found the electrical component at position U5 to be charred, as some of the numbers are unreadable. The designation I can read is TDA72 and maybe a 9 and the last number is gone. If I had the complete component number I could order it from the electronics store and see if I have any luck as the part is only $10. it should be TDAxxxx. I emailed Polk last week and did not get a response. As these are only $90 new at Amazon, I am reluctant to put a bunch of money into the repair. Thank you for your advice and time. It was made in 2005.

[Kenneth Swauger]

Hello,
It might be a good idea to call Polk's CS guys at 1-800-377-7655 for part information.
Regards, Ken

[ckp]

Alex from customer service emailed me with the part number of the IC and a couple tips. Kudos to Polk and Alex!

Thank you

[ckp]

Ah well, replaced the amp IC and have the same problem. So much for an easy fix. Using an old receiver amp I had lying around and bypassed the OE amp. Works fine, a bit obtuse with that receiver on top. LOL

[DracoAmericanus]

Have you checked the drive transistors at the output? the power supply feeding that ic could be damaged as well, something caused that ic to fail and that is what needs to be tracked down, one itty bitty diode could even take out all of work just done, even a bias problem can do that, it is highly likely that the part that ruined that ic is still lurking inside waiting to strike another new component down

[deronb1]

I wonder if Polk needs to look hard at the amount of problems people are having with this sub. I know it doesn't cost much, but it bears the Polk name.

[ckp]

Have you checked the drive transistors at the output? the power supply feeding that ic could be damaged as well, something caused that ic to fail and that is what needs to be tracked down, one itty bitty diode could even take out all of work just done, even a bias problem can do that, it is highly likely that the part that ruined that ic is still lurking inside waiting to strike another new component down

Thank you for your reply! I'm sure you are right about the problem still lurking inside. I was an automobile mechanic for over 30 years, so I have some electrical knowledge. Unfortunately, my experience repairing sub amps is nill. Without a schematic and/or proper direction, I do not know how to check these components with my Fluke multimeter.

Thanks again.