mozartfan, The E80CC is a European designation for a tube. The European designation for the 12AU7 is E82CC and for the 12AT7 it’s E81CC, for example. I don’t know if there is an American designation for the E80CC.
Different tubes have different electrical characteristics. You need to check with the maker of your Defy 7 to make sure that the E80CC’s electrical characteristics won’t damage it over time. It’s really not a good idea to substitute different tube types without finding out if they’re compatible with the equipment.
I checked at Brent Jessee Tubes and it appears that the E80CC is considered a substitute for the E82CC with the caveat that you check with the manufacturer about suitability:
E80CC / 6085:This unusual European tube is basically an industrial type 6085. However, it’s specs are similar enough to a 12AU7 that audiophiles are grabbing them up while the prices are still reasonable. The heater life is rated at 10,000 hours, and some have gold pins. The larger box plate structure gives this tube low microphonics and silky smooth sonics. Since this tube has a much higher Gm and Mu factor than a 12AU7, the gain is going to be greater and this tube will give a more forward presentation. Awesome in phase splitter applications. If in doubt, check with your amp or preamp manufacturer to see if this tube will work OK in your application.
Different tubes have different electrical characteristics. You need to check with the maker of your Defy 7 to make sure that the E80CC’s electrical characteristics won’t damage it over time. It’s really not a good idea to substitute different tube types without finding out if they’re compatible with the equipment.
I checked at Brent Jessee Tubes and it appears that the E80CC is considered a substitute for the E82CC with the caveat that you check with the manufacturer about suitability:
E80CC / 6085:This unusual European tube is basically an industrial type 6085. However, it’s specs are similar enough to a 12AU7 that audiophiles are grabbing them up while the prices are still reasonable. The heater life is rated at 10,000 hours, and some have gold pins. The larger box plate structure gives this tube low microphonics and silky smooth sonics. Since this tube has a much higher Gm and Mu factor than a 12AU7, the gain is going to be greater and this tube will give a more forward presentation. Awesome in phase splitter applications. If in doubt, check with your amp or preamp manufacturer to see if this tube will work OK in your application.