Any change in tonality with a 6H30 based preamp will depend on the circuit and
power supply design, rather than the specific tube.
Even then, the 6H30 tube and 6H30 based designs will all sound neutral, (i.e.
solid state).
Short answer, there are 6H30 tube options (6H30 and 6H30DR), but neither will
have a sweeter midrange than the other, IMO.
power supply design, rather than the specific tube.
Even then, the 6H30 tube and 6H30 based designs will all sound neutral, (i.e.
solid state).
Short answer, there are 6H30 tube options (6H30 and 6H30DR), but neither will
have a sweeter midrange than the other, IMO.

