The Fuxtor
Addicted Member
I built one for a 400 receiver, but I think the install procedure for an 800 is slightly different? The bias resistor R119 is removed as well as two caps ( can't remember offhand ) are replaced with new board caps. Is there a 0.01 uf cap that should be removed? Or is this left causing no issues?
I was gonna try building an IBBA this time, but the tubes in my unit are old stock RCA 7591 which so far bias fairly close ( -18 v equates to around 28ma via pin3) with one tube being slightly stronger at 32ma. From what I have read the IBAM will be more helpful with bringing these more similar. I think for the sweet spot I look for achieving 34ma?
Charles
I was gonna try building an IBBA this time, but the tubes in my unit are old stock RCA 7591 which so far bias fairly close ( -18 v equates to around 28ma via pin3) with one tube being slightly stronger at 32ma. From what I have read the IBAM will be more helpful with bringing these more similar. I think for the sweet spot I look for achieving 34ma?
Charles