There are more parts than tubes in an amp that affect sound. I have replaced noisy metal film resistors in $12,000 amps that had gone high resistance and very noisy.
Replaced them with wirewound resistors for better than original sound.
Of course coupling caps have been a target for replacement and should be explored. Power supply caps also has an effect.
The emission and gain characteristics from tubes is very voltage dependant. You could tweak the filament voltage a bit up or down, maybe 10 or 20% to see what effect it will have.
Replaced them with wirewound resistors for better than original sound.
Of course coupling caps have been a target for replacement and should be explored. Power supply caps also has an effect.
The emission and gain characteristics from tubes is very voltage dependant. You could tweak the filament voltage a bit up or down, maybe 10 or 20% to see what effect it will have.