Amp innards - technical people: please help

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benecol

Amp innards - technical people: please help

Post by benecol »

Hi all: cracked open the Vibrochamp today:


Image

Looks pretty neat, eh? Now, I wanted your advice as I'm a little confused. Online, everyone is saying that the electrolytic capacitors inside these amps can go bad, and need changing every ten years or so (mine's from 1979,and looks all original inside). Weber will send them to me for about $80... Now, both Torres UK and Watford Valves here in the UK have said to me that if there's no hum or hiss on the amp, and no obvious discolouration or buckling of the cap cans, then I needn't change them; Torres went so far as to say that when they get silverface stuff in, unless there's anything wrong, they leave well alone.
I suppose what I'm worried about is primarily damage to the amp, and secondarily, impaired sound quality: however, the amp sounds lush (and will sound even better when my new speaker arrives), and I've been told (Watford and Torres again) that there's usually a fair bit of warning before a cap goes, and the worse that can happen is the fuse blows, or at worse, a valve.

So what do you think I should do? Spring for the cap kit, or stick with it as is?
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Reece
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Post by Reece »

If it aint' broke...
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Will
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Post by Will »

You will get a fair bit of warning - buckling and discoloration are one sign. The main audible one is random shifts in volume when yr playing loud (amp loses about 3db for 30 seconds or so, then recovers).

If you want to replace them, you'll get some peace of mind. If not, that's cool too. It will have to be done eventually. Just make sure when you notice them going bad that you fix it, otherwise you'll be getting an output transformer too.
benecol

Post by benecol »

I get the feeling that if I don't do it now, I'll keep just lunching it out, plus I've just had a bid on my TT so funds are guaranteed; I'll buy the caps. Thanks for your input.
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Mike
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Post by Mike »

I would just leave it. When they go it will be an easy fix generally.