Thanks Vmhf. Bob amps used to come with NOS smooth plate Telefunken 12AX7 and RCA or GE 12AT7, which were a great combination. From what I understand, the current signal tube are crappy Chinese signal tubes. If you can get the high quality Chinese Psvane 12AX7/12AT7, you will even surpass the NOS combination. More extension in the bass/treble, more air, better soundstaging and imaging, etc. For Maggies, may be the 300 watt Black Beauty may be a better match.
I have a little secret to share with you if you want to improve the sound more than what high quality signal tube can do. And it's affordable. You will significantly increase bass impact and dynamics (may rival your SS amp), among all the other improvements I've talked about. Replace the stock volume control pots in the amp with Gold Point stepped attenuators (~$160). You will be shocked at the improvement. If you are handy with soldering iron or have a local tech, this is the best mod I've done on this amp. A more expensive mod is to put in four 0.22 uF Teflon Vcap as output caps. These two mods will take these amps to a whole new level. Bob's circuitry is rock solid and installing high quality key parts can make this amp sound just incredible.
I have a little secret to share with you if you want to improve the sound more than what high quality signal tube can do. And it's affordable. You will significantly increase bass impact and dynamics (may rival your SS amp), among all the other improvements I've talked about. Replace the stock volume control pots in the amp with Gold Point stepped attenuators (~$160). You will be shocked at the improvement. If you are handy with soldering iron or have a local tech, this is the best mod I've done on this amp. A more expensive mod is to put in four 0.22 uF Teflon Vcap as output caps. These two mods will take these amps to a whole new level. Bob's circuitry is rock solid and installing high quality key parts can make this amp sound just incredible.