Treasure 6SL7-Z: “I have never heard bass like that from ANY amp”

Treasure 6SL7-Z pair in box with logoFeedback received from Nick B. in UK about Treasure 6SL7-Z:

“Hi Rachel,

I just thought I would drop you a note having put the 6SL7-Z tubes into my monobloc amps.

The only word I can think of to use is WOW!

I have never heard bass like that from ANY amp, never mind a valve amp. What a difference it has made to the music.”