New Amp on a Sub is good as new?

[Kleinst]

I had what I think is pretty good luck last weekend picking up a system for a bedroom unit.

Got some smaller ML towers and center (Motion 40 and 30), and Marantz AVR and a SVS PB1000

Far I can tell all is great except the PB1000 would not output any sound. Guy of course thought it worked fine. It did turn on and had a light so not sure if he just thought it was putting out bass and it was the rest or something happened when I hooked it up but I never got any output.

Anyways the AMP has a cap that appears to have had an issue. Burned or black around it. SVS indicated need a new plate amp and I bought one. It's in route

Two questions

1) For that little plate amp is trying to get it fixed worth it if it's a single cap? (I have no idea how to do that)

2) The driver and cabinet seem in relatively perfect condition. With a brand new AMP, do I essentially have a subwoofer that is GOOD AS NEW? I've not had a sub fail in anything but the AMP. So in my mind, the life of this thing starts over as soon as the new AMP goes in.

Thanks

 

[Eppie]

SVS gear is generally engineered fairly well, so the odds of the speaker being damaged are small. You can expect years of use with a new plate amp if the speaker is fine.

Most gear these days use switching power supplies and all it takes is one bad capacitor for the whole thing to stop working. If the LED comes on, then the power supply is likely working, which is worrisome. Caps don't usually get burned or black. They tend to bulge out or leak when they fail. The burn marks are likely from a component next to it but I am just guessing without seeing it first hand. If it's just the cap, it's an easy repair. If something next to the cap went up in flames then you're looking at a lot more work.

If it's just the cap, caps are cheap and there are plenty of tutorials on desoldering and soldering on YouTube. If you're new to repair, you will need a soldering iron, solder (electronic, not plumbing) and a desoldering tool like a manual suction tool or solder wick (fine braided copper wire). The value of the cap will be on the case, so wipe of the charring with alcohol and get a cap of the same value and size. If you can't read the value, get it from the new amp.

If you don't mind investing in the parts and equipment, this can be a learning experience. If replacing the cap doesn't work, it's no big loss since you have a new plate amp. Do some homework first, though. Capacitors hold a charge so even if the amp is unplugged there can be high voltages present. Any large capacitors on the power supply or amplifier stage need to be discharged before you can safely work on circuitry. You also need to connect it to the mains (120V) for testing so proper precaution needs to be taken. If you are not comfortable working with potentially dangerous voltages, then leave it to the pros.

 

[Kleinst]

SVS gear is generally engineered fairly well, so the odds of the speaker being damaged are small. You can expect years of use with a new plate amp if the speaker is fine.

Most gear these days use switching power supplies and all it takes is one bad capacitor for the whole thing to stop working. If the LED comes on, then the power supply is likely working, which is worrisome. Caps don't usually get burned or black. They tend to bulge out or leak when they fail. The burn marks are likely from a component next to it but I am just guessing without seeing it first hand. If it's just the cap, it's an easy repair. If something next to the cap went up in flames then you're looking at a lot more work.

If it's just the cap, caps are cheap and there are plenty of tutorials on desoldering and soldering on YouTube. If you're new to repair, you will need a soldering iron, solder (electronic, not plumbing) and a desoldering tool like a manual suction tool or solder wick (fine braided copper wire). The value of the cap will be on the case, so wipe of the charring with alcohol and get a cap of the same value and size. If you can't read the value, get it from the new amp.

If you don't mind investing in the parts and equipment, this can be a learning experience. If replacing the cap doesn't work, it's no big loss since you have a new plate amp. Do some homework first, though. Capacitors hold a charge so even if the amp is unplugged there can be high voltages present. Any large capacitors on the power supply or amplifier stage need to be discharged before you can safely work on circuitry. You also need to connect it to the mains (120V) for testing so proper precaution needs to be taken. If you are not comfortable working with potentially dangerous voltages, then leave it to the pros.

Thanks for your response. I think these would be amazing skills to have especially with as much stuff I like to buy and a lot of it used. So there will always be a chance of getting something like this. In this case, since the plate amp is ~$150-$200, i'm guessing they are kind of disposable for most people. Now if it was a $2000 amp then I'd be feeling a whole lot different. I'm not sure I'm ready to venture into this now but I might keep that bad amp around in case I want to learn. As you said it might be a no risk opportunity to learn how to do it. Or I might find a friend who enjoys these things one day.

New plate amp comes in today I think so fingers crossed that's all it was and it will work like new. Still, I don't know what caused the last issue and I assume it was like that when I got it as all I did was connect it.