Leave it alone and get a couple of sealed 8 - 10' sealed port (small) subs and be very happy. I NEVER use tubes for bass in my main system. Just doesn't work. 25-50 watts will do great from 60-100hz and UP.
Below that is the BLOATED BASS issue typical of valve amps.. SS is always better. You can't EQ what you don't have without a SQ price. HEAVY bass really taxes valve amps. They do pretty good doing one or the other but both, not so good. Easy fix.. Get a little sub an place it right under your rump. :-) No just kidding.. though that is close.. maybe right behind your chair. OR A pair right behind on either side.. close to the side walls. No ported though...Want to get fancy servos.. 8-10" yup.
Regards..
Below that is the BLOATED BASS issue typical of valve amps.. SS is always better. You can't EQ what you don't have without a SQ price. HEAVY bass really taxes valve amps. They do pretty good doing one or the other but both, not so good. Easy fix.. Get a little sub an place it right under your rump. :-) No just kidding.. though that is close.. maybe right behind your chair. OR A pair right behind on either side.. close to the side walls. No ported though...Want to get fancy servos.. 8-10" yup.
Regards..