For sell one tube ECC808 NOS/NIB Siemens, West Germany made, tubes and box in perfect condition, full test results in pics.
Available tube #3, tube #2 from pics was sold. All tests done, excellent NOS tube.
Important note: ECC808 is not direct replacement for 12AX7 / ECC83. Broadly is the same tube, in fact a much better one than any kind of 12AX7/ECC83 but different pinout for heater. In tubes' datasheets you can find any information about this or ask us.
Because of the variation of terms in the formula of gain (Rp, Gm), gain value of a tube is not an exact fix value, is in a range, usually we measured for 12AX7/ECC83 values in range 83 - 100, for ECC808 100 - 120.
Quote: 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.
[Ratheiser Röhren - und Transistoren - Handbuch 3. Aufl. 1964]
Tested using professional tube tester system Roetest V10, the best existing tube tester.
Price is for 1 tubes , the buyer will receive exact tube #5 seen in photos + printed test protocols, very safe packaged in a box.
We ship usually next day after payment, priority airmail with tracking number.
Look to our other listing to save using combined shipping.
LOT: C120