Peavey Classic VT , only one valve lighting up?

robgilmo

I came across this on the verb, apparently works Ok but only one tube lighting up.
Surely that cant be right can it?

ICBM

At very low volume it will sound OK because a Class AB amp doesn’t run the valves at cut-off at idle, but if you turn it up further than the point the single valve goes into cut-off, you then only get half the waveform above there and it sounds distorted.

robgilmo

ICBM said:

At very low volume it will sound OK because a Class AB amp doesn’t run the valves at cut-off at idle, but if you turn it up further than the point the single valve goes into cut-off, you then only get half the waveform above there and it sounds distorted.

So it will run on one then, sounds like more trouble than I want to spend on one, thanks fella.

ICBM

It will only just barely run on one. The question is why the other one isn’t lighting up - a dead valve is a possibility, but so is a faulty valve socket or a bad solder joint. It shouldn’t be a big repair either way.

randella

You can tell I've got a job to do that I don't want to start when I've gone down a 70's Peavey rabbit hole

I dug out the schematic here:

http://adrsoundsense.co.uk/technical/peavey/Classic VT.pdf

There's a 6.3VAC tap for the filaments that's referenced to ground on one side. No virtual centre tap gubbins, about as simple as it gets. If one of the 6L6's heater isn't working, there's not an awful lot between the PT secondary and the valve to go wrong (as per ICBM's advice). If one's lit, the 6.3VAC must be present somewhere nearby.

I did also find the ad (probably nudged there by Google after reading this, it was the first link that came up. I'm not stalking - honest!). There does seem to be a contradiction in the copy - 'very loud' and 'one output tube not working' can't both be true, surely?

Apologies if this is telling you everything you already know, I just fancied a bit of detective work

randella

Not suggesting you buy it by the way - unless you're up for a rabbit hole, I'd swerve it and look for a working one maybe.

robgilmo

randella said:

Not suggesting you buy it by the way - unless you're up for a rabbit hole, I'd swerve it and look for a working one maybe.

Thanks fella, I am not adverse to a rabbit hole now and again but you are probably right, trying to find a first real amp on the cheap for my wee man is proving problematic, probably because of where I live, all the amps within budget seem to be well into my old car might not make it territory and if it did 22mpg is the limiting factor.

Perhaps I should be looking for a more economical car instead!

snowblind

Nah. Old cars with 54itty gas mileage rule! 24 year old BMW V8 owner here.

If you are looking at the Peavey VT I would strongly suggest you also look at the Laney VC options. Got a VC30 212 on the cheap a little while back and it is proving to be a really good find. I've switched the original Celestion Seventy-80s for HiWatt speakers and it's pretty damn good. Not quite Vox territory given it has 4xEL84s in the power section but bright with lots of detail. It has an on-board reverb (digital) which is a bit meh but I tend to turn that off and use a pedal do the job. One on verb right now for £185. Looks like it comes with free cobwebs but don't let that put you off.