ecc808 6kx8 Siemens Germany tube preamp tubes quad valve same code c60 D5F1
4 tubes = four vintage vacuum tubes Siemens ECC808 = 6KX8
Tested on tube tester Funke W19
reference good at 1,8mA & 1,8mA
test tube 1 = 3mA & 2,5mA code c60 D5F1
test tube 2 = 3,1mA & 1,9mA code c60 D5F1
test tube 3 = 2,6mA & 2,6mA code c60 D5F1
test tube 4 = 2,8mA & 2,2mA code c60 D5F1
all 4 tubes with same code , same inner structure, same O getter
with red tip selected
same old stock production
ECC808 = 6KX8
dual triode
The ECC808 is a low hum, low microphony and low crosstalk dual triode for high sensitivity AF amplifiers, especially for two channel stereo circuits. The static values of the ECC808 are practically identical to those of the ECC83. Unlike the ECC83, however, the ECC808 is only intended for parallel heating (6.3 V / 0.34 A).
In combination with a more practical socket circuit by improved shielding and better cathode isolation, a particularly high freedom from hum could be achieved. (Ripple voltage at G1 approx. 4 μV with pin 4 at ground.) The microphony resistance could also be improved by a factor of 3.
Due to the good shielding between the two systems, loudness and clarity controls can also be arranged between the two stages without difficulty in the case of cascade amplification. With two-channel amplification, a crosstalk attenuation of -50 dB at 10 kHz can be achieved.
box 152