I have a peavey xr 700 and i want to replace the caps on the power amp board . They are the old style foil caps rated at 0.1 uf. At around 50volts. They have a red stripe on one end. So i dont know the polarity of these caps. On the schematic it shows them being electrolytics . So can i replace these with newer style CAN style electrolytics ? I also need to know the polarity. Does the red stripe mean that is the negitive side or the positive side ? Dunno . please someone let me know these two questions. Hopefully Enzo will see this thread or someone with in-depth knowledge on older peavey powered mixers. Thanks.
I don't have the power amp schematic for that handy. Two 100 watt channels?
But in general, foil caps are not electrolytics, and foil caps have no polarity. Foil caps do have an "outside foil" which is often indicated by a stripe. Some guys will argue about outside foil, but in this amp I sincerely doubt it maters.
Unless they are damaged or failed, there is little reason to replace them.
I know there are electrolytics that small, but I have never seen them in a Peavey product.
Can you post your schematic here?
But in general, foil caps are not electrolytics, and foil caps have no polarity. Foil caps do have an "outside foil" which is often indicated by a stripe. Some guys will argue about outside foil, but in this amp I sincerely doubt it maters.
Unless they are damaged or failed, there is little reason to replace them.
I know there are electrolytics that small, but I have never seen them in a Peavey product.
Can you post your schematic here?
I'll have to second what he has said. If it isn't broke don't fix it. One simple question for you...is it working correctly? No hum no noise? Changing caps isn't going to make this piece sound any better. Its a simple guitar amp of medium to low quality designed to provide modest performance at a reasonable price. If its working ok button it back up and use it.
Jon, the power amps are a separate schematic, it is a stereo 100w/ch, but I cannot recall the card number. The few I have in my computer are not a match, I will look in my paper files when I can. The OP seems to have the schematic, hoping he will post it. Otherwise customer service at Peavey will send it upon request.
Thanks guys for all of the info . yes it is working now. The B channel was real crackerly but i found the problem on board with all of the xlr 1/4 " inputs and outputs it was a corroded 4558 op amp on that board. Someone had spilt liquid in it and corroded that op amp. Unit works great now. But i thought whilebi was in it inwould go ahead and replace those foil caps on the output board . But now i see i dont have to. I did replace the power supply caps which were 5000uf rated at 55volts with 4700uf rated at 63 volts.Again thanks for all your input. Now on to my next project which is a Crest CA 9. power amp. It had a bad channel which i found a shorted output xtor. To 262 case. Costomer wants back in stereo instead of bridged. It has no external switch for that but i called Peavey and talked to Grant the lead tech there and you have to switch it to stereo inside the amp theres 3 pins with a two pin connector and have to physically take that connector off and replace it on the other 2 pins.Wish me luck on getting it up to specs. You guys are great and it is so cool to have you guys in my pocket. Have a good one guys and good luck on all of your endeavors.
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