Abill
I have about 500 hours on my Shuguang Treasure Series(Black glass) tubes. They sound wonderful and have been reliable.I got them from Grant Audio for 600.00 per pair, not cheap but I have no complaints. The Frankenstein MK2 amps are top tier and deserve premium tubes. Israel Blume has warned amplifier owners about premature failure with these KR tubes,
I have about 500 hours on my Shuguang Treasure Series(Black glass) tubes. They sound wonderful and have been reliable.I got them from Grant Audio for 600.00 per pair, not cheap but I have no complaints. The Frankenstein MK2 amps are top tier and deserve premium tubes. Israel Blume has warned amplifier owners about premature failure with these KR tubes,