My buddy built them. His building skills are outstanding. I have restored a number of tube amp/preamp over the years, but in this case, may as well have it built by a pro.
The transformers are custom built by Heyboer. The output transformers are spec'ed at 120 watts.
All the chokes are NOS. There is additional chokes inside the chassis. Each of the power supplies are choke filtered. All the tubes have DC filaments. The amp is VERY quiet, and the extra work on the power supply results in outstanding low level detail playback. This is very important when listening to classical music.
The exact circuit for the front end is proprietary, so I can't post it. What I can tell you is that its very close to the Mastero amp from the 50's. I included the link for the circuit in this post.
The resistors for the audio circuit are 1 watt PRP. Used Jupiter bypass coupling caps, and German power and coupling caps. Hexfrd diodes. NOS tube sockets (MIL) from the late 40's/early 50's. Cardas copper binding posts, and vampire RCA jacks.
http://oestex.com/tubes/maestro.htmlhttp://www.mif.pg.gda.pl/homepages/frank/sheets/049/6/6146B.pdf
