Marshall dsl 50 problem

[mazbury]

Hello every one my name is chris....this is my first post on this forum.......

I was wondering if someone could help i have a dsl50 which seems to not be working correctly. ....
With a two dvm connected to the bias pins i'm not seeing any swing on the bias...its just static....
I've fitted a new tube pcb as the old one was around 10 years old but the problem is still there....
When i play a chord i would expect to see the bias swing....
I've tried different tubes in the pre and power amp sections still the same.....
No blown fuses ..... bass response doesn't seem quite right.....kind of clippy....

Would any one be able to help.....

[danman]

Do you have a bias probe that you could plug into each socket to check the current draw on each tube? It would really help to know what is happening at each socket? If the amp has lost all negative bias voltage then the tubes would redplate almost instantly. Can you check for negative DC bias voltage at pin 5 on each power tube socket?

[mazbury]

Hi everyone,

The amp is now fixed.......i took it to a local tech..turn out to be some bad components on the tube board....

Thanks to everyone for your help...