jazzman37

[jazzman37]

I have a kx1200 behringer I did the stupidest thing put an input into the headphones jack now the BUZZ. is it fixable?

[The Dude]

Most everything is fixable. Do you have electronics knowledge,.....meter,.....tools,... schematic, etc.?

[jazzman37]

everything but the schematic

[The Dude]

Well, tougher without one, but certainly not impossible. Open it up. Look for something burnt. We don't know what it is without a schematic, but there's probably some sort of amp for the phones- maybe some little 8 pin op amp looking thing? It may be shorted. Trace the phones output and see where it goes. Look up the datasheet for that part and see where the supply pins are. Check the supply pins- maybe +&-15V? Check the other pins for DC. Does the amp put out any DC or lots of AC? Check with your meter. If so disconnect the speaker and leave it disconnected until you get the thing fixed. Let us know what you find and we can go from there

[Enzo]

WHAT buzzes? Just the headphones jack? or does it buzz out the speaker too?

I googled "KX1200 schematic" and poof, Elektrotanya has it. Never hurts to look for it.

BEHRINGER KX1200 Service Manual free download, schematics, eeprom, repair info for electronics

Considering the output is just a pair of LM3886 in parallel, I suspect one of them failed.

[Jazz P Bass]

kx1200.zip

If the amp was amplifying at the time, you probably fried the LM3886 pair.

[jazzman37]

it buzzes or hums with headphones too thank you for the schematic

[The Dude]

The headphone out is just "resistored down" from the speaker output, so I'm betting on a LM3886 problem.