My amp has gone into a vegetative state.

[jmanpc 5,000+ posts]

Somewhere between alive and dead.

It's a MB Quart DSC4125. I've been running it HARD since the day I bought it. I've got it running my mids up front at 4 ohms stereo, and one sub bridged at 2 ohms. Yes, I know this is beyond the ratings and I knew I would kill it eventually, so shut it.

Anyhow, it plays well until I get on the volume. When I get the volume above ~65%, it'll play loud and clean, and over the next 30 seconds, slowly degrade into a muddled, unrecognizable mess. If I back off the volume, it goes back to sounding clean until I crank again. I checked all the wiring and it's all clean and tight (because that's the only way I do it //content.invisioncic.com/y282845/emoticons/suave.gif.858fc102f7646e678ee8af7e1fbc41d1.gif)

Sounds like a fukked power supply to me. Agree? Disagree? Input?

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[o. l. t. 10+ year member]

Power supply capacitor.

 

[ltr450racer690 10+ year member]

agreed

 

[jmanpc 5,000+ posts]

I suppose I'll crack it open tonight.

 

[jmanpc 5,000+ posts]

Cracked it open. Nothing amiss. None of the capacitors are bloated or oozing. Everything looks to be in ship shape. Is there any way to test the capacitors? I don't wanna get it fixed because honestly, I'd rather spend $135 on a brand new amp than $100 getting it fixed. If anything I could just solder in some new ones myself for shits and giggles.

My only other guess is that my front mids are going, and are shorting out the amp. That could happen, right? They're Polk DB coaxes, and I've just been giving them the beating of a lifetime (125w to their rated 60w.) So, if they're only shorting out at high excursion, could it could cause the amp to malfunction?

 

[Team Maxxsonics 10+ year member]

Disconnect the subwoofer and try again.

It's likely the 2-Ohm load.

2-Ohms bridged is the same as running stereo at 1-Ohm.

Not recommended.

 

[nateberrier 10+ year member]

Its not worth your time to bother with anything but maybe the transistors. Sounds like youre dropping your load for the sub too low, Any of the cheap amps Ive used below their rated impedance will play fine till you turn it up, then do what youre describing.