“Shiny Eyes” PSE with my cherished 4P1L DHP in triode mode
I was working for quite a while (on and off) on my second amp from the series “Shiny Eyes”.
It is a 2 stage single ended amp, using Lundahl ITs and OTs. All tubes are 4P1L and filament biased. Driver biased at 155V/35mA/-8.5V loaded on a LL 1692A Alt”T” (2:3.5) step up. Final stage is a PSE 2x4P1L biased at 245V/35mA/-21V loaded on a LL1664/70mA. All filament biased using Coleman regulators and driver stage using a SSHV (K&K audio clone with Kevin Carter’s approval). Amp gain is about 14dB (1Vrms input leads to 5Vrms on 8ohm output).
It was little challenging to solve the problem of driver’s microphonic behavior. A careful selection of the driver tube, starving filament at 550mA and rubber suspension took care of the above issue.
Sound is amazing and can’t wait to finish my Alpair12P cabinets soon.
Right now the amp cabinet is finished and the amp is assembled. I am working on the power supply that will be enclosed in a separate cabinet. Hope to see it finished by the end of January.
PSU Coming soon…