There's some technical jargon.
■Modify power amp to use EL91 tubes for total power around 4.8W (that’s right).
■Use 6N2P(-EV) tubes in preamp instead of standard 12AX7. The only change made to accommodate these beauties is different heater wiring.
■Added Depth control.
■Reduce fx loop Send level to be more pedal friendly. I added 1K resistor in parallel with existing 2.2K resistor on Send triode cathode resistor. To compensate gain loss, Return triode cathode resistor is bypassed with 1uF capacitor.
■Switchable treble bleed capacitor on OD channel gain pot, a.k.a Warren Haynes mod.
■Only 8ohm output jack installed without impedance switch.
■Removed choke from the power supply. With less current draw from power tubes, RC filters should provide enough filtering for B+ (tested in Duncan PSU Designer).
■Changed bias power supply to AX84.com style. This is a slight change, I just wasn’t sure if SLO bias can go as low as 10mA per tube.
■Added switch to choose between 2 and 8 ohm OT taps for NFB loop. 2 ohm means less NFB and it makes amp sound a bit more aggressive.
It's coming to me from a friend in Serbia.