Swart ast problems. Anyone seen this before?

WarrenD

WarrenD

New member
SWART AST Amp was set to low volume (about 2) & all dials less set than 4. Guitar was cranked up all the way into an EHX soul food also cranked all the way..heard some feedback...it got louder..then.WHACK ..amp was just screaming.. Not in a good way...Not playing anything at this point. Shut everything down. Unplugged the guitar, turned everything off then on... Unfortunately now the "space" nob (Swarts version of reverb) causes massive feedback type noise when it's turned up past 1. Made a video of the problem with the amp.

https://youtu.be/BXbxKrF4ZfY

Anyone seen this issue before? On any amp?

Is my amp toasted? Or is this a simple fix??

Really appreciate some advice on this.. Thanks.


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Re: Swart ast problems. Anyone seen this before?

I have no experience with Swart amps and haven't had that happen. But there seem to be a ton of Swart people on The Gear Page, so there may be some helpful replies over there.
 
Re: Swart ast problems. Anyone seen this before?

Hey - we said what you REALLY need is a new amp. Sounds like this is a sign....
 
Re: Swart ast problems. Anyone seen this before?

WarrenD said:
Yes indeed.


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Click to expand...

Great offer for you. I'll take that little combo off your hands. I'll pay the shipping. Deal? :bigthumb:

Besides the noise when turning up the space/reverb control, does the amp work otherwise?
Got any spare tubes? Worth a try swapping preamp tubes first.
 
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Re: Swart ast problems. Anyone seen this before?

My Carvin did that when the reverb tube went microphonic

If there is a tube involved swap it
 
Re: Swart ast problems. Anyone seen this before?

ehdwuld said:
My Carvin did that when the reverb tube went microphonic

If there is a tube involved swap it
Click to expand...

Thx for the tip. So there are several tubes in this 6v6 combo. Any suggestions how to tell which is the culprit?


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Re: Swart ast problems. Anyone seen this before?

The reverb valve is a 12DW7 which is not a common valve but you could put a 12AX7 in there to test if the noise/screeching is coming from there.

ast_hang_manual.jpg
 
Re: Swart ast problems. Anyone seen this before?

chances are it is one of the preamp tubes. (the little ones)
Get replacements for all three.
Turn the amp off.
Replace the first one.
Switch it back on.
If that doesn't fix it, turn the amp off again.
Replace the second one.
If that doesnt fix it switch the amp off and replace the third one.
Once you know which tube has crapped out, throw it away and keep the other two as spares.

Tubes are like car tyres. They wear out, and you should always carry a spare.
 
Re: Swart ast problems. Anyone seen this before?

If the amp works otherwise, probably the 12DW7 (V2). As suggested above by Gibson175, get spares for both the 12AX7's and 12DW7. If you can swing it, you may want to consider picking up two 12DW7 spares (just in case you are sent a bad one) along with the 2 12AX7's. Personally, I like to have spares on hand (and I do) for every tube type that I use. Power tubes can get a bit expensive but I'd rather have spares ready to go in case, or when, I need them rather than have to wait on them when I do need them.
 
Re: Swart ast problems. Anyone seen this before?

Mark Sampson founded Matchless, Bad Cat, and Star amps.... some of thw best built amps on earth, just like Swart.

One time I asked him about a weird noise, and without asking any questions, he responded "it's a tube." That's how confident he was about his components and build quality.

I'm not saying components like reverb tanks don't fail, but problems with high end amps are almost always a tube failure.

Every tube amp owner should have a stash of as many spares as they can get their hands on.
 
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