Peavey Max 115 Bass amp

[Goldpanner]

Hi,

I have a Peavey Max 115 Bass amp that was working fine and it blew the 1.5 amp slow blow fuse in the power supply.

I checked all the diodes, resistors, capacitors in and around that area, no burnt parts, soldering connections are good.

I'm suspecting the power amp IC seeing as this was a used amp that seen some gigs All I get is a hum from the amp, the 3amp fuse is good.

I was thinking of replacing the IC OP and the power amp IC as a set seeing as they are linked, and they are cheap enough to buy.

I don't have a schematic for the unit yet, was just wondering if anyone else ran into this problem, there is not much "under the hood" of this amp so it shouldn't be too hard to fix.

I checked the speaker and the voice coil is not locked and it reads 4 ohms with the cables disconnected.

Thanks for any help you give

[Goldpanner]

Update I just called peavey and they e-mailed me a schematic for free Excellent customer service

[Artie]

Thanks for that info. I have a MAX 112 myself, and would like to have a schematic also. Mine works perfectly, but its still nice to have. This is a great 'lil amp for the money. Hope you get yours sorted out.

[Goldpanner]

Well an update, I traced it down to the Audio amp IC, part number LM3886TF, it was shorted, and other parts in and around the area tested good, I'm replacing the op/amp IC at the same time, cheap insurance, part number CA3080E, was able to get all the parts on Ebay for less then $20.00 and that is doubles, 2 of each IC, back-ups

I ordered the parts, when I get them and install them I will let you know how it goes, I can't believe no on on this site has had this trouble before, these audio amp IC's are pretty common at failing, and it is a real common amp IC.

[Goldpanner]

Hope this helped someone, I know 98% of this site is about building and designing amps but repairing them is important too, I don't design amps just repair them.
Too bad there isn't more of that on here seeing as how big this forum is.
There are common repair issues for most of the popular amps that could be posted and could help others repair their own units by saving money and saving down time at the repair shop.
And I just couldn't imaging packing up a 100 pound amp to be shipped to a repair depot, by the time you got it back after being tossed around what would you have left.
Anyhow just a thought, maybe not such a good thought seeing how little response I received on this thread
This repair set me back less then $20.00.

[Iain McNeill]

I agree. I enjoy reading the equipment repair threads, the challenge, the intrigue and (hopefully) the final joy of success.

[Enzo]

ANy product that uses an IC power amp will blow one from time to time, especially in a musical instrument amp, which sees a lot tougher service than home stereo gear. Usually a new power IC is all it takes.

Whenever an amplifier blows fuses, the standard approach is pretty much look for a shorted output device (be it tube, transistor, or power IC), and then look for a shorted rectifier in the power supply, and finally shorted filter caps - in that order. Of course other things could be wrong, but for fuse blows, that covers 99% of it.

This DIY forum concentrates mainly on hifi applications, though there is a musical instruments section here down below. If you want to discuss mostly musical instrument amplifiers, the building and repair thereof, you might also visit www.music-electronics-forum.com. A lot of tube talk over there, but we do discuss solid state as well.

[ppnoraseng]

hi every one her

i have
Peavey Max 115 Bass amp to reapir but i do not have schematic
can some one help?

[llwhtt]

I have the schematic, what's your email.

Craig

[ppnoraseng]

Hi llwhtt
thank you
please send schematic to my pnoraseng@yahoo.com
sith