Marshall Valvestate 8040

Valves for Marshall Valvestate 8040 amplifier.

The Marshall Vlavestate 84040 is a solid-state amplifier that uses 1 x ECC83 preamp valve (also known as a 12AX7) which works on the clean and crunch channels.

Those people that like this amp (including me) absolutely love what it does but that preamp valve should be changed every so often as it will lose tone and power over time.

Eventually, it will start making odd noises before finally packing up altogether.

The JJ ECC83 is highly recommended for this amplifier and you will notice the improvement straight away. The original valve on Valvestate amps varies but is often made in China. The JJ will certainly give you a much better sound and overall tone.

Swapping the valve on a Marshall Valvestate 8040 amplifier.

It is relatively simple to swap it out. The old valve simply slides out on its pins, a little wiggle will help, and the new one slides in.

On some amps, Marshall has fitted a plastic collar around the valve which will need to be carefully cut off with a scalpel blade.

Another problem that has been reported over the years is a fluctuation in volume.

If replacing the valve does not help, and you’re having volume problems, plug in a patch cable when you’re not using the loop. It often solves the volume drop out problems.