No distortion in a Marshall Valvestate 100v Model 8100 Head

[cleberrs]

Hi everyone.

Yesterday I had a gig with a Motörhead tribute band and, to my surprise, my Valvestate 100w head had no distortion by switching it to BOOS CHANNEL. Instead, it sounded just like NORMAL CHANNEL.

The red led lights up for boost channel but it just sounds clean, no distortion at all.

Anyone any idea?

Thanks in advance.

Cleber

 

[Anode100]

If it were mine, I'd check the following :-

With the 'Boost' red LED lit - do any of the boost channel controls make a difference to the sound?

If so, you have channel switching, but no gain.
If not, you have no channel switching.

If you have no channel switching, start with a good switch cleaner in the channel switch (or footswitch if you're using one).

...or, try swapping out the 12AX7 for a known good one.

 

[fraser]

I have an old valvestate 8080.
Bought it from a buddy when it was brand new, early nineties.

Had big problems with the board mounted pots and switches. Amp did some crazy stuff at times.
Parked it about a dozen years ago,
I'll maybe pull it apart one day and try to breathe some reliability into it or something.

But yeah, try the tube, if not look to see if the switch and pots are all still firmly soldered in place and functioning.

 

[Mike_LA]

YAh, sounds like a weak valve if all your switches are working.