Difference between ECC88 and E88CC Tubes?

The ECC88, is the European designation, for a 6DJ8. Although some manufacturers, warn against using American 6DJ8's, in their gear, because of the lower voltage handiling capabilities, they are generally,interchangeable. An E88CC, is the European designation,for a 6922, and was made to be the industrial upgrade, to a ECC88. It is a higher spec'ed tube, than the ECC88/6DJ8 ie; noise, microphonics, longevity, failure, higher voltages capabilities, to name a few. One of the easiest ways, to tell them apart, is the specifications, for an E88CC, called for coated pins. Most are gold plated, some are chrome plated.

Since you have the data sheets handy, you'll see that the 6DJ8/ECC88 is slightly lower in MU than its brothers the 6922/E88CC and 7308/E188CC (which are identical I believe.)

For the most part, you'll be able to use all three tubes and each designation has its good and bad. Be careful that you check for microphonics first (ask) as a noisey tube is not fun. This family is prone to it.

Ed gives good advice re: Richardson Electronics and you really need to be careful about paying top dollar for new production garbage.

Go to WWW.AudioAsylum.com and look for Joe's Tube Lore in the FAQ section. He gives a pretty comprehensive subjective evaluation on what to look for physically in a tube and what he hears. While it's not absolute, it's a nice primer course.

Good luck, Chris

Be aware that Richardson (RELL) owns the amperex name and can label whatever they want "Amperex". THese are most likely either 80's vintage phillips or recent manufacture Russian tubes. In no way are they connected to the quality of the original Amperex 6DJ8s. It's very misleading, but given that they own the trademark, no one can really do much about it except educate each other. Stay away from these, IMHO. Vintage Amperex are some of the best 6DJ8s available (considering they invented that type of tube...frame grid design). These from RELL are just crap and dont' desvere the name Amperex (IMNSHO). BTW, E88CC and ECC88 are just the European designations for 6922 and 6DJ8, respectively. If you want some nice *real* vintage amperex Bugle Boys, email me or check my ad here on Agon. Have many pairs for sale.

-Ed Sawyer