Marshall Amp Forum - View Single Post - SuperBass EL34 to 6550 bias circuit INFO need PLEASE

David_Well · 10-31-2009, 09:07 PM

Yep , this question again....
My Goal is to target the Most perfect BIAS as possible.
I need to know witch value of resistor i need to Swap for Winged"C" 6550
It for a SuperBass 73 PCB (you know how is to mod on PCB...All tweek in same time)
I Really whant to get fix before open it....
I still Asking the question cause so many people say different thing's about the cercuit.
Now my bias is way too mutch...
What do I need....

Split 82K,220K or 150K
NFB 4 or 8 ohm
In line with the diode, 47K,56k or 100K
down the board 15K or 27K
8Uf or 10Uf twin cap....

What I whant is to get Headroom And Kick when crank-up and for shure , Elephant Ball's TONE !

Thanks and best regards to All
Dave

10-31-2009, 09:07 PM	#1 (permalink)
David_Well Member Join Date: Mar 2009 Posts: 67	SuperBass EL34 to 6550 bias circuit INFO need PLEASE Yep , this question again.... My Goal is to target the Most perfect BIAS as possible. I need to know witch value of resistor i need to Swap for Winged"C" 6550 It for a SuperBass 73 PCB (you know how is to mod on PCB...All tweek in same time) I Really whant to get fix before open it.... I still Asking the question cause so many people say different thing's about the cercuit. Now my bias is way too mutch... What do I need.... Split 82K,220K or 150K NFB 4 or 8 ohm In line with the diode, 47K,56k or 100K down the board 15K or 27K 8Uf or 10Uf twin cap.... What I whant is to get Headroom And Kick when crank-up and for shure , Elephant Ball's TONE ! Thanks and best regards to All Dave Last edited by David_Well; 10-31-2009 at 10:10 PM.