Favorite 300B: Sophia vs KR

Antigrunge,
Excellent question; and even though this thread is about 300b tubes, the small tubes and their influence on power tubes should probably be addressed. Like Charles1dad, all my small tubes are old, scarce and expensive. But if you’re contemplating any of these very expensive 300bs, please spend the requisite time and energy and yes...money on the small tubes to get the best out of these very expensive 300b tubes. You wouldn’t put run of the mill tires on a Bugatti.

Phaelon,
You `re so right. My amp`s builder Israel Blume says the driver tube selection is critical to the output tube`s performance.He picked the 6EM7 specifically for it`s high current drive capacity(this driver tube can put out 2 watts of power on it`s own per Israel).

True to their word, the new Takatsuki TA-300b prices are posted as either 133,400 or 140,070 yen. It is hard to figure out the improvements; but using Google translate of a press release, there seem to be improvements in quality control and tolerances.

It is hard to determine what or if there are any 'sonic' improvements. To my understanding there are`nt any 'internal' changes to the tube. Time will tell.

I hope to visit Amtrans in July with someone who speaks Japanese. Even if there are sonic improvements, I am not sure that I would be able to tell. Perhaps they are predicting better longevity?