BIJOU ON STEROIDS
I have already built two Bijou in past years, a really good headphone amplifier; the first was an original version with all components as shown in the schematic, the second in the first time I had recalculated with Multisim and Spice models to use russian 6N1P-EV and 6N6B-I with no NFB and was already a bit better than the original.
This year I wanted to go one step further and design a pumped Bijou! Since I have many russian tubes 6N23P and 6S19P I wanted to redesign it to use these great tubes. After a few weeks of study and trials with Spice models and Multisim I built this new version of Bijou:
Bijou on Steroids.
The scheme remained the original, only the values of the components are obviously changed, I have used resistors in place of the diodes, no NFB. Even the power supply is changed, I went back to a classic diodes and RC filters.
The first time I turned it on I was very impressed: no noise, no hiss and no buzz. And the sound... WOOOW !!!!! really spectacular with my headphones (Beyerdynamic DT 990 Pro and the Sennheiser HD590).
This is confirmation that the Alex Cavalli Bijou circuit is really a great project where there is room to do even mods.
I have built and designed many headphone amps: transistors, hybrids, tubes but this is the best headphone amplifier that I made.