Hi,
I made a bflex for my bass player a few months ago. It was working fine but, even if I added a line out, it was good for practice, but too weak for the rehearsals with our heavy rock Drummer.
So he asked me if I could upgrade it to 100 Watts.
Here's what I did :
Replaced PWT and OT with your Soldano 100 Watts ones.
replaced the 2x6V6 by 4x6L6GC
Replaced the PI Tube with a ECC82
Added a Hammond 159Q choke.
Kept the TT PSU mini CT, but added 2x220 MF for B1 (so I have 210 MF for B1)
Added 2x2 UF5408 before the D1 and D2 of the PSU.
Added a Standby just before B1, So the 210 MF are charged First.
Fuses of 4AT AC Input, and 2AT HT
R6PSU is now 22 K
Screen resistors = 470 Ohms 5W
Grid stoppers = 10k
NFB Resistor = 47 K on the 16 Ohm Tap
R19 of the Paraphase invertor is now 517 K to minimize the unbalance (still unbalanced though)
Bias taken on the 60V tap of the PWT, R101 is now 4.7K
B1=480V, B2=477V, B3=361 V, B4=351 V Bias -53V
6L6GC Biased at 40 mA (I installed 1 Ohm resistor on the Cathodes)
for 1 Khz sinus input, I got 110 Watt RMS under 8 ohms
The amp so far is working great, very powerfull on 4 ohms with two Ampeg cabinets 1x15.
