newbie questiun on E88CC and ECC88

They are AFAIK, direct replacements in the 6922/6DJ8/7308 family. But you will get loads of opinions on which are the best in which product in which position. Try Joe's Tube Lore at audio asylum for detailed descriptions of just about every variant of each tube family. However, be aware that Russian and (I think) Chinese companies have bought the rights to many of the premium NOS tube names and there are widely varying opinions about their quality and sound. There are also TONS of fakes and pulls being sold as NOS, esp on Fleabay.

Google Brent Jessee for a good explanation of the differences.

6DJ8 heater current = 365 ma may not be best for/in all 6922 circuits*
7308 hc--------- = 335 ma " " " " " *
6922 hc--------- = 300 ma the "cool" one

* Check with manufacturer

Hi Calbrs03,
The Brent Jesse pages are perfect and some evenings worth of reading, thanks for pointing this one

You're welcome, Vinylmeister. Good luck hunting.