Line 3SE owner for 5 years, only had to re-tube once last year and I had 6H23 in them before without ever noticing any tube noise thru out the 4 or 5 years of usage. Given the life span I got from the tubes, I would rate it as gentle on the tubes.
Yes, you can get better sound by putting in NOS. But I have been using cheap tubes (EH or NOS Sovtek) in buffer stage with good success.
Yes, you can get better sound by putting in NOS. But I have been using cheap tubes (EH or NOS Sovtek) in buffer stage with good success.