Marshall Silver Jubilee

[TIMBO]

Hi guys, The Little Booga given me a major headache so i think i'll stick it in the cupboard for a rainy day(i need to get a proper chassis made in the hope it will help with the HUM and other things.

Got around to listen to some music by Joe Bonamassa (live at albert hall) good stuff
Found a schem.Looks good
Have a plexi build thats good for parts and cab
I think i'll do it

Question, it has a 25/50 switch for lower power but i'd like to use a VVR. Can i have a cathode bias that would give me a similar sound/tone as a fixed bias and remove this switch for low volume.The VVR i have is for a cathode bias only and i don't want to have to order form the US.

Also it has some diodes (LED) that i am unsure about (type, voltage,etc.)
Not had much to do with relays ( do have a couple ) so what voltage would they need to be?
Just had a look and it has a 5vdc coil and 250vac@ 8A switch
Thanks

[LooseChange]

I did a Desktop Silver Jubilee with a single ended EL34. Used any diodes I could find following the plans with 2 red LED's and 3 4007's (you can see them in the picture).  I did a panel mounted panel switch only.  Any relay will work but If I was doing it I would use a PT with the 5V windings and dedicate to thee switching.
The tone controls are the most responsive of any Marshall I have ever played.
The distortion channel sounds very good.  Bonamassa claims to set all controls on '10'.

[LooseChange]

Didn't look at the schematic until after I posted.... If you use the GZ34 forget my relay suggestion.  I really don't see why you need that.
And about the VVR... Cathode bias the amp and go for it!!

[TIMBO]

Thanks for the reply LC, The marshall schem does not have the rect tube and is not a must have, so the 5v supply can be used for the relay. Any thoughts on the resistor/cap combo for the cathode. Thanks