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Messages - Meshuggah333

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After studying the amp a little closer my guess is it's a problem with the switching input jack, it switches the preamp out when you don't plug a cable in.
Unplugged state : input is wired direct to the power amp (it seems), certainly to prevent noise from the preamp when nothing is plugged in.
Plugged state : input is wired to the preamp, but it seems the path to the power amp is still ON, and it should be OFF. So that create a parallel signal. The signal leaking through is perfectly clear tho, like it's the full signal from the pickups into the power amp.
If it's as I guessed, it's an easy fix. But there might be something else going on, I won't know until I open it up.
The input part of the amp seems fishy anyway, as it doesn't properly load the pickups and brings a lot of noise on the Hi input and a lot less on the Lo input.

As said, stomp boxes with a lot of hi end are unusable, as the piercing hi end leak through to the power amp.
Try to use a fuzz into the effect return of your amp, and you'll know what I mean.

I've tried with all the knobs on zero, it's the same.
Fuzz boxes tend to generate a lot of hi end which is fine when it's mostly filtered out by the preamp tone stack, but here the piercing treble bleed through to the power amp. That sounds pretty bad.
Same boxes sound fine on other amps.

Hi, thx.
Playing the amp by itself, the bleeding isn't a problem. But I love stomp boxes, and some of them have a very hot output and sounds nasty direct to a poweramp (most fuzz sounds terrible that way) and make the bleeding very audible and hard to manage.
So that could be a dry solder joint on one of the pot? I'm planing on extracting the amp from the combo in a few days, pots are in bad need of love with contact fluid, I'll check for bad solder joints.

Tubes and Hybrids / Proamplifiers VSQ 65 combo having a weird problem
« on: June 21, 2016, 04:39:41 AM »
History :
This amp is a gift from a friend, it took dust in a corner as he wasn't using it anymore. I don't really know what happened to it in the 26 years it's been out of the factory :D
I just know the preamp was retubed 2 years ago (some GT 7025 in V1,V4 and GT 12AX7 in V2, V3. Done by idiots and thieves but that another story)
It's from the Proamplifiers brand from Suffolk, England. The brand did a lot of amps in the 70's, 80's up to the mid 90's then did crash due to them being dependent of the US market (through the KMD brand) and basically loosing their only contract.

Problem :
If I cut all volume down, on any channels, I still hear a faint signal from the input.
Let me explain: it's as if even with the preamp completely cut off, I had a slight bit of input signal leaking through to the power amp.
This is even more obvious when I put a pedal that boost the input signal a lot, it sounds like a wet/dry signal (with distortion/fuzz pedals it's just horrible)

Do any of you have an idea of what ​​the problem might be?

The amp inputs 1/4" connectors are switching the preamp in and out of the signal path (they are switching connectors, I imagine it was done to prevent noises when nothing is connected to the amp), that might be coming from that but I'm not sure...

I'm certainly going to send it to a tech for a check up but I'm trying to solve most problems before that.

This is not mine but I have the exact same.

My first post and I already need help  ::)

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