#1
So I'm a gigantic idiot and took my new-to-me Ampeg to a show last night without a backup. When I bought it, the guy told me that the amp starts to cut out after 5-20 minutes of usage, and needs some work, so I got it for a good price. Then I take it to our jamspace and we practice for a total of about 12 hours on it over the course of a week with absolutely no problems with the volume at 5, which is really f***ing loud. I just assumed that the guy didn't know what he was doing, and was doing something to cause to to overload. He really had no idea about how anything worked with these, and couldn't even tell me what the gain knob did.

So come last night, I haul it up to LA for a battle of the bands to get on an upcoming metalfest. It was a big night for us, and of course, my amp craps out right away, 5 seconds into the first song. I tried to get it going, but couldn't, so I just ended up singing only, leaving my other guitarist on his own (who plays most of the leads, and doesn't really know my rhythms). It sucked, and the judges were not sympathetic to our situation at all, with one of them yelling at us that we need to get our shit together. Not a good night.

Anyway...

From what I'm reading, the solder joints wear out and once heated up, can separate, causing the amp to cut out. It's a pretty common issue with these mid-early 90's Ampeg SS amps.

My question is about how I need to go about working on this thing. I am comfortable with soldering and have a technical background, but I'm not too familiar with working with amps. I know that these things have capacitors that hold massive amounts of current, but how do I go about draining them? Is it as simple as just going in there and shorting the capacitor leads? Is this even relevant to a solid state amp? All the info I have been able to find only mentions tube amps, so I'm not sure how similar the process is for working on them.

I used to work IT for a restaurant company, so I had to fix and resolder a lot old POS systems, but the max current any one of them would hold was less than 12 or so volts, so I want to be a bit more careful working with something holding enough to deliver a fatal shock.

Any advice you guys can give would be very helpful. I don't think I need to take it in to a tech, but I will if need be -- but from what I have read on forums, this is a fairly simple fix for anyone who has basic knowledge of soldering.

Thanks!
#2
Look at the capacitor voltage ratings when you open it up. SS is generally a lot lower than a tube.

What part of town are you in?

Edit: I normally measure the voltage stored in the capacitor. If you don't find anything above 5v DC then you are all good. If you have to drain it maybe a 100K resistor across it.
Quote by DeathByDestroyr
See, it's important that people clarify when they say "metal", because I pretty much always assume they are a Cannibal Corpse fanboi.
Last edited by R45VT at May 12, 2013,
#3
That sucks hard dude. You really should've brought a back-up, especially after what the previous owner had said. I bet your kicking yourself now. There's a first for everything I suppose (assuming this ain't the first time )
"Air created the greenness. And once you've got something, that leads to otherness." - Karl Pilkington.
#4
Quote by ExDementia
...

From what I'm reading, the solder joints wear out and once heated up, can separate, causing the amp to cut out. It's a pretty common issue with these mid-early 90's Ampeg SS amps.

My question is about how I need to go about working on this thing. I am comfortable with soldering and have a technical background, but I'm not too familiar with working with amps. I know that these things have capacitors that hold massive amounts of current, but how do I go about draining them? Is it as simple as just going in there and shorting the capacitor leads? Is this even relevant to a solid state amp? All the info I have been able to find only mentions tube amps, so I'm not sure how similar the process is for working on them.

I used to work IT for a restaurant company, so I had to fix and resolder a lot old POS systems, but the max current any one of them would hold was less than 12 or so volts, so I want to be a bit more careful working with something holding enough to deliver a fatal shock.

Any advice you guys can give would be very helpful. I don't think I need to take it in to a tech, but I will if need be -- but from what I have read on forums, this is a fairly simple fix for anyone who has basic knowledge of soldering.

Thanks!


Unless they are all cold solder joints....BULLSHIT.
Proper solder joints in and of themselves do not wear out.
However...
Circuits boards are mounted in such a way that they are allowed to flex.
Or if the circuit boards themselves are of poor quality.
Soldering the same connections on any PCB can cause the pads to lift though.
Particularly on low quality boards.
These can all cause poor solder joints to separate.
Last edited by CodeMonk at May 12, 2013,
#5
I always have a spare just in case, sorry to hear about your luck.

I have stopped doing battle of the bands, because in my area 99% of it is how many people you can get to go to the venue not the actual talent of the bands. In other words it is for bands who already have a fan bas and not a new band
2002 PRS CE22
2013 G&L ASAT Deluxe
2009 Epiphone G-400 (SH-4)
Marshall JCM2000 DSL100
Krank 1980 Jr 20watt
Krank Rev 4x12 (eminence V12)
GFS Greenie/Digitech Bad Monkey
Morley Bad Horsie 2
MXR Smart Gate
#6
Quote by CodeMonk
Unless they are all cold solder joints....BULLSHIT.
Proper solder joints in and of themselves do not wear out.
However...
Circuits boards are mounted in such a way that they are allowed to flex.
Or if the circuit boards themselves are of poor quality.
Soldering the same connections on any PCB can cause the pads to lift though.
Particularly on low quality boards.
These can all cause poor solder joints to separate.

Sorry, I couldn't think of the term. Yes, they are cold solder joints, and are pretty common for this model -- at least that's what I'm assuming the problem is, since quite a few people have had this same problem.

I really doubt that it's a poor quality board, it may be solid state, but this is still a US built Ampeg, and from what I read, wasn't cheap when it was introduced.

But yes, I'm kicking myself pretty hard right now Also, I'm down in San Diego.
#7
Even worse that you drove from San Diego. bummer.
Quote by DeathByDestroyr
See, it's important that people clarify when they say "metal", because I pretty much always assume they are a Cannibal Corpse fanboi.
#9
To do it properly you should pull out the board, resolder the pots and switches and then go over the rest of the board with a magnifying glass looking for joints on the board where the solder doesn't look like it has flowed properly.
Take photos as you go so you can look back at how it was before you pulled it out.
Gilchrist custom
Yamaha SBG500
Telecasters
Randall RM100 & RM20
Marshall JTM45 clone
Marshall JCM900 4102 (modded)
Marshall 18W clone
Fender 5F1 Champ clone
Atomic Amplifire
Marshall 1960A
Boss GT-100


Cathbard Amplification
My band
#10
Quote by Cathbard
To do it properly you should pull out the board, resolder the pots and switches and then go over the rest of the board with a magnifying glass looking for joints on the board where the solder doesn't look like it has flowed properly.
Take photos as you go so you can look back at how it was before you pulled it out.
Should I strip out the existing solder on the joints, or just go over it? I think I still have a solder sucker around here somewhere. Taking pictures is a good idea, thanks for that.
Quote by Ippon
Crap! I told you so, in the original thread:


I know!! I'm so pissed at myself. I almost packed my Carvin, but it just kept running through my head that its been absolutely perfect for multiple 5-6 hour long jam sessions. To quote South Park, "I didn't listen!"


Another issue I noticed is that the effects loop acts a little strange. It fades in and out as I play, like I'll hit a note and it will sort of fade into it and then back out once the signal weakens. I'm guessing that's something I'll have to look for once I pull the board out
#11
You shouldn't need to. Just hit it with the iron and reflow the solder. The only time you should need to introduce new solder is if they basically totally missed the joint and there isn't enough there already to do the deed.
Gilchrist custom
Yamaha SBG500
Telecasters
Randall RM100 & RM20
Marshall JTM45 clone
Marshall JCM900 4102 (modded)
Marshall 18W clone
Fender 5F1 Champ clone
Atomic Amplifire
Marshall 1960A
Boss GT-100


Cathbard Amplification
My band
#12
Quote by Robbgnarly
I always have a spare just in case, sorry to hear about your luck.

I have stopped doing battle of the bands, because in my area 99% of it is how many people you can get to go to the venue not the actual talent of the bands. In other words it is for bands who already have a fan bas and not a new band


This

Our band lost to a cover band who played Smoke on the Water and Umbapp (Hanson)... First and only time I'll do that
Gear:

Squier Strat
Epiphone Explorer
Agile AL-3100

No AMP
#13
Quote by evmac
This

Our band lost to a cover band who played Smoke on the Water and Umbapp (Hanson)... First and only time I'll do that

Well I'm not even saying my band should have won, just the people who won sure as hell did not deserve to.
Stay away from Gorilla Music, they are a absolute joke, they basically pick the winner by how many tickets you sell.
2002 PRS CE22
2013 G&L ASAT Deluxe
2009 Epiphone G-400 (SH-4)
Marshall JCM2000 DSL100
Krank 1980 Jr 20watt
Krank Rev 4x12 (eminence V12)
GFS Greenie/Digitech Bad Monkey
Morley Bad Horsie 2
MXR Smart Gate