D-Moll volume problem

[githero]

Hi!
I have a problem with the volume setting of the clean channel. First I thought I would be wrong and the lower volume is caused by fx settings. But on monday we had a recording for some sample tracks and i could see it in the recording software.
First, all 2,5 channels had the same output-level (same volume level). But after about 15 minutes, the volume of the clean channel changed to a lower level without any changes at the amp. Clean channel then was a bit piped down compared to the other channels.
Has anyone an idea, what might cause this volume change?

 

[bananaladonpcp]

any time you have a problem with your tube amp, try swapping out the tubes. Even if they are brand new.

 

[JimmyBlind]

Forgive me if this is beneath you, but check the clean channel gain. Has anyone turned it down? I usually set the gain as high as possible to the point where I'm happy with a very small amount of clipping, then regulate the volume. The channel volume on the clean isn't as responsive as the gain.

After that, try the tube.

 

[githero]

Forgive me if this is beneath you, but check the clean channel gain. Has anyone turned it down?
After that, try the tube.

The gain stays at the same level. No one touches the amp. The lower volumen happens without any changes at the settings.

If the tubes are the problem: is this a case for warrenty? The amp ist almost brand new (3 month old)

 

[JimmyBlind]

Forgive me if this is beneath you, but check the clean channel gain. Has anyone turned it down?
After that, try the tube.

The gain stays at the same level. No one touches the amp. The lower volumen happens without any changes at the settings.

If the tubes are the problem: is this a case for warrenty? The amp ist almost brand new (3 month old)

I guess tubes can last anywhere between 1 day & 10 years. I'd almost treat them like getting a puncture while taking your new car home from the garage. I'm not sure whether free tyres is covered under a car's warranty.
I've blown both fuses in both of the VH4's i've owned, within a couple of hours of turning the amps on. I kinda accept that fuses blow.

The amp itself will be under warranty, but the tubes are a consumable I guess. Rest assured that they will have been burned in & tested before leaving the workshop. Diezel seem to run a pretty tight ship.
Change out the pre-amp tube for that channel & if that's the cause, speak to PD on here & see what he says. He's really helpful.

 

[steve_k]

The channel volumes are the FX send levels when you are in the loop. If it was a preamp tube, it would like affect all the channels. The tube layout is set up like a Herbert;

V1 Used by all channels

V2 Used by channel 3

V3 Used by all channels

V4 Mixer & Loop Driver

V5 Return Driver

V6 Phase Inverter

Are you using the parallel loop, series or both?

 

[githero]

I´m using the parallel loop.
So you think it couldn´t be a tube problem when it only affects the clean channel?

 

[steve_k]

I´m using the parallel loop.
So you think it couldn´t be a tube problem when it only affects the clean channel?

Never say never. I don't know how the triodes are laid out, but V1 is the input tube for everything and V3 is the cathode follower. It makes sense that if you loose clean from V1, then everything else falls off as well. The easiest thing to do is take a new tube or a known good one and start trying it in V1, V3 and V4.

If you remove the FX from the parallel loop, does it respond normally? Are these pedals you are running or a multi-FX?

Email Peter. He will zero in on it for you. He should be finishing brunch about now.


Steve

 

[bananaladonpcp]

I guess i just assumed that you did this..... But have you tried plugging your guitar directly into the input with no effects and see if it still has the volume loss?