Beskrivning från Eurotubes:
Factory description: Special grid plated by gold to reduce microphone interaction and noise.
My observations: The ECC83S is great tube with a tight low end, a very natural and harmonically complex mid with VERY good definition and a sweet high end that is not brittle. These tubes have very low microphonics and are great in the gain stages of high gain amps like Marshall's, Meas's and Peaveys to name a few.
The best part is that you can buy a new tube that sounds this good for one tenth the price of an NOS Telefunken.