I recently updated my Dynaco Mk III with
6SN7 OCTAL DRIVER board
SDS Labs Cap Board
The tubes are not new and are old GE Kt88
Old GZ34 rectifiers
Warm up the amps, run some music through them. Completely flat no soundstage no bottom end. No dynamics. Seem like my top end is muted as well. My Bryston 3B runs better.
Any suggestions.. Im gonna guess replace tubes and rectifier and try again. but thats a 300$ gamble.
All items were installed correctly.
All functions as it should ..
Testing was on a pair of Kef 103/4 speakers 4 ohm. low impedance 89db.. this should only affect volume but not dynamics or soundstage.
I had far higher hopes for the units.
They arrived partially unassembled so prior testing and comparing was not possible.
Compared against my Dynaco ST70 and the ST70 sounds better. Not amazingly better but better. More full, better top end, still a little flat. Newer tubes and rectifier. mostly original ST70, no mods.
Any suggestions or comments welcome.
If i can't get the sound out of these i want I'm gonna ditch the MK III and buy a Class A Krell.