Peavey PV23XO Crossover Repair and Enhancement

[clearchris]

This crossover was bought new about 12 years ago, and has probably been powered on for at least 3/4 of that time. It also has a recently developed horrible sound on the second channel, sometimes it's a wub-wub-wub, sometimes it's just a hum that comes and goes. It's not noticable if something is playing (it may be gone), but it's quite noticable if there is silence.

Because of age and problems it's due for a recap. I'm also strongly considering putting in sockets to potentially replace the 12 ST TL072 opamps. For such a small device, it's still going to be over 30 screws to take out the pcb, so while I have it out...

Does anyone have an opinion on replacing the TL072 opamps? From my research, the TL072 are very common, and also very commonly hated. However, they aren't always easy to replace because they are JFET.

Also, anything else that should be replaced while I'm in there? I think the film caps should still be good, pots are nice and smooth, resistors have no discoloration.

Thanks!

[CapLeaker]

I just would replace all electrolytic capacitors, check for (potentially) bad solder joints, take a few measurements, clean the sucker (clean and lube switches and pots) and put it back together. If it is something important that needs to be fixed, I take pictures and have spares on hand, Would I go as far and socket now all the JFET's simply because I am there now? No. It ran for a long time already.
It all depends on how important this amp is. I've got a few amps in a commercial application and I do have a spare amp and spare parts.

[clearchris]

I just would replace all electrolytic capacitors, check for (potentially) bad solder joints, take a few measurements, clean the sucker (clean and lube switches and pots) and put it back together. If it is something important that needs to be fixed, I take pictures and have spares on hand, Would I go as far and socket now all the JFET's simply because I am there now? No. It ran for a long time already.
It all depends on how important this amp is. I've got a few amps in a commercial application and I do have a spare amp and spare parts.

It's actually the youngest, cleanest piece of equipment in my rack aside from the raspberry pi. 😂 Non smoking house, and the box is pretty well sealed. Kind of surprised it needs a repair already.

Everything looks hand soldered, so you have a good point about checking solder joints. I hadn't expected this to be a hand soldered, through hole board, but it is (and that's a good thing imho). I'll see what's under there after I take out the 30 screws...

Thank you!

[clearchris]

In case anyone wants to do a recap, here's a listing of the caps in my Peavey PV23XO Crossover. My stock didn't quite cover me, I had to put an order in, so I don't have results yet.

6x  10uf  50v
10x 22uf  25v
2x  47uf  25v
2x  100uf 16v
2x  470uf 35v​

[sam_sam_sam]

In case anyone wants to do a recap, here's a listing of the caps in my Peavey PV23XO Crossover. My stock didn't quite cover me, I had to put an order in, so I don't have results yet.

6x 10uf 50v
10x 22uf 25v
2x 47uf 25v

These capacitor values are prone to failure because of the value and there physical size especially in switching power supply and if see these values I replace them on site even sometimes if they are brand name capacitors especially if the device is giving trouble just to rule out the possibility that this is issue

[clearchris]

These capacitor values are prone to failure because of the value and there physical size especially in switching power supply and if see these values I replace them on site even sometimes if they are brand name capacitors especially if the device is giving trouble just to rule out the possibility that this is issue

Yeah, I replaced all of them with higher voltage rated caps, turns out one of the TL072CN opamps is gone, or at least that's what I suspect. The pots feel buttery smooth, and the distortion doesn't sound pot induced. I added DIP sockets yesterday, haven't gotten a chance to swap some opamps to different sockets and test to confirm my suspicion.

My dillema now is, since the TL072CN is obsolete, what do I replace it with? In further research I have found that people speak highly of the TL072ACP, but there are a few different values that concern me, particularly output current per channel going from 40ma with the tl072cn to 10ma with the TL072ACP. Thoughts? Spec comparision below.