Here some photos of the finished push pull 300B monos and some initial sound impressions.
All tests on the raw amps have been completed and they got their final housings.
One of the amp chassis in it's beautiful walnut case.
The back side with the connections.
The power supply:
Power supply back side:
The stereo combo consisting of 4 chassis:
Close ups to the tubes of one channel:
Top view of all 4 chassis:
And of course the big question, how do they sound, especially compared to the single ended amps?
They exhibit quite a different character. While single ended amps can tend to be euphonic and more on the forgiving side. These are extremely clean sounding and well controlled. Very direct, but never loose the musicality or flow.
And of course lots of power with excellent bass control. Are they better than single ended amps? No, just different. The choice is a matter of taste. If you want a sound more on the romantic side, the single ended amps are the choice. If you like clean and well controlled sound (probably closer to the truth). These are the ones to go for. Especially the lack of capacitors in the signal path is showing with a very un coloured and high resolution reproduction.
With the ample power and low output impedance they can drive a wide range of speakers.
The sound of these grows more and more on me and I will give another update after living with them for some time. An ultimate version of these amps with all silver transformers and plate chokes is already firmly planned! Which probably says more about their sound quality than any description...
Stay tuned for more impressions of the differential sound!