If you have a standing offer from a tech to build you a tube amp, first of all find out how much cash they need today and wire it to them.
Then ask yourself why you cheaped out and bought junk, instead of hiring your friend, to do what he does professionally.
Then you told him...
That seems rude...
Maybe try asking him, if he would still consider building you an amplifier, then let him. Dont come to us for opinions on what to tell him to do, hes the builder, the artist.
I'm one of those people who will build amplifiers for those who ask and who I deem worthy, a truly skilled craftsman. If you have the opportunity to buy a work of art from a skilled craftsman, but you buy a run of the mill department store quality amp, I dont think you understand what a privilege it is to be able to commission an amplifier, and recieve it with your name engraved in the back.
You seem to not have a clue what you want.
Since you know a friend in the biz, I recommend calling him, and listening to his recommendations. He can demystify topologies, impedance matching, transformers, distortion profiles, power bandwidth, and maybe even teach you how to read a data sheet. Once you two decide on a path forward, find out what he needs to get started and pay him.
The folks who can do this work are dying from the face of the earth. Transformer vendors closing left and right. If you want their work, now is the time to bust out that cash and pay up. In a decade most of the builders won't be with us any more. The industries which fed us will remain shuttered forever.
