Le 18/02/2025 ¨¤ 20:13, John Woodgate a
¨¦crit?:
The heater voltage is 12.6 V or 6.3 V, not
6.0 V.
Preamp tubes are very often heated at reduced
voltage, for noise optimization.
Particularly in condenser microphones, where secondary emission
(grid current) is to be avoided at any cost. E seies (6.3V
nominal) are often run at 5.5-5.8V.