I just uploaded a profile of my Marshall Studio 15.
Its an amp I used in the mid to late 1980,s.
It uses 6V6 output tubes and has a unique sound.
15 watts.
I remember the filaments or heaters of the tubes had their own DC supply to reduce hum.
It was designed for studio use and that is just how I used it.
Its up on Rig Exchange now.
Bill
[Blocked Image: http://www.zikinf.com/_gfx/matos/dyn/large/marshall-4001-studio-15.jpg]