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I've had an Ampeg SVT-7Pro for a few years and one of the ICE2A165 chips overheated. Apparently this is a common problem with earlier models of the amp. I took the amp to my repair man and he mentioned that the chip replacement itself is very challenging/expensive, but replacing the board may be an option. I found a replacement board with an upgraded chip ("revision H" of the amp) for a few hundred bucks which should be pretty easy to self install.

However, my tech mentioned that many of today's Class D amps are notoriously fragile and once broken, they are often more expensive to repair than to replace. He said that if the amp is light, small, and powerful, it usually falls into this category.

I love the SVT sound and controls, so I'm wondering if I'm better off getting one of the big heavy SVT-3 or 4 Pros. They only have a two year warranty when I look at most online stores, but would they be easier/cheaper to repair in the event of a fault? I want an amp that lasts a long time.

UPDATE 1: Here are pictures of the chip explosion. It took other parts with it. I'm curious what those other are and how easy it would be to replace them all (I'm sure they're cheap.) I can solder, I just don't have all the fancy diagnostic tools. Spending $20 and some spare time seems worthwhile, so I don't have to buy a new amp .

Top view

Bottom View

UPDATE 2: I found the three parts online that were destroyed:

  • The ICE2A265 (upgrade from the ICE2A165)
  • One US1M diode to go in space D9
  • One 1-ohm/1-watt resistor for space R46

I'm going to try soldering these in using the schematic and see what happens.

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    I took a glance at some photos of the SVT-7 Pro's board and it seems that the amp chip is soldered to the board, rather than socketed. This is most likely the main issue with repairing them, as THT-soldered ICs are notoriously hard to remove without damaging other components on the PCB. The SVT-4 Pro apparently shares this issue, again judging by photos on the interwebs. (Side note: being too cheap to use IC sockets in a $700 piece of gear is a very bad engineering decision.) – user70370 Jul 29 '20 at 19:34
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    @Taschi there shouldn't really be any need for sockets – Ampeg's fault is using an IC that's not up to the task! And, come on, replacing a THT IC isn't that difficult. An SMD one – yeah, though even that is doable. – leftaroundabout Jul 29 '20 at 20:15
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    @Taschi don't use a heat gun. Unsolder the legs individually with a desoldering pump, then simply pull the IC out with small pliers (it'll still require some force because of flux residues, but shouldn't be so much that you risk damaging the board). – leftaroundabout Jul 29 '20 at 20:23
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    Swapping the IC, even with a regular iron & vac-pump is not the tough part. The tough part is figuring out what else it took down with it - & that might not only be the bits that look charred, it might be anything one or two steps away down the PCB track, &/or the track itself. Get a pro to do it. I had my favourite Dynacord go down last year & it cascade-failed half the components. – Tetsujin Jul 30 '20 at 9:28
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    Yeah, looking at the photos, I take back everything I said yesterday. It's not like a socket would really help here. – user70370 Jul 30 '20 at 18:26
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The U2 ICE2A165 chip should be replaced by an ICE2A265 (just as cheap). It's a standard 8-pin IC; if I was working on that board, I'd pull the broken chip, insert an 8-pin IC socket and then use the upgraded chip (it has better thermal properties). Talk to another repair man - this doesn't seem like a challenging or expensive fix.

enter image description here

  • Thanks! When the chip exploded, it took other parts with it. I'm adding images to the OP. Also, how much trouble is it to insert the socket? I've soldered guitars before, maybe I could probably do this myself. – JacobIRR Jul 30 '20 at 2:07
  • Inserting the socket is exactly as much trouble as inserting a new IC: you put it into the holes and then you solder the pins. So, trivially easy. But TBH i think you should AT THE VERY LEAST replace the charred resistors and caps, check that the PCB paths are still conductive, and check all other components within the fat white line. (I assume U8 and the DIP next to it are optocouplers and provide galvanic separation so the stuff outside the fat white line might be less likely to have taken damage?) – user70370 Jul 30 '20 at 18:14
  • Soldering PCBs is different from soldering wires / leads together "in the air", so maybe get yourself some prototype PCBs and try a handful of joints on there. – user70370 Jul 30 '20 at 18:21
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    @taschi Soldering a socket in place has most of the hassles of soldering an IC, except that you're not worrying about local heat build up. I agree with replacing all the visibly damaged components. – PeteCon Jul 30 '20 at 18:35
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    @PeteCon, yeah, that too. My point was, there is no downside to putting in a socket. – user70370 Jul 30 '20 at 18:51

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