The U70 amp described above was built by my prototype technician, but as a favor to this seller, not sold by or through AVA itself. Thus the AVA warranty does not apply.
It should be solidly and correctly built and have the last "wire switch" update. I do not know the origin of the chassis used, but definitely not one that came from us. I also do not know the source of the power or output transformers, but that seems to make little difference in the performance.
Right now I am happiest with the Electro-Harmonix big bottle 6CA7 tubes in our tube amplifiers. This unit appears to have JJ EL34 output tubes, which work well too, but to my ear are a tad brighter sounding.
The $995 asking price is fair. We would ask that for a U70 factory wired into an original Dyna St-70 chassis in good conditon.
Note that for best long term tube and component life, run the amp with the cover off unless there is a risk of children or pets coming into contact with the very high voltage on the exposed audio circuit board. Be very careful regarding that.
Regards,
Frank Van Alstine