6L6GC Power output comparison
Andy Ruhl
Date: circa Nov '98


Testing conditions:

Amp: Fender Bassman 100 w/ Kendrick 2x6L6GC output transformer
Plate Voltage: 430vdc
Idle Current: 35ma (or as near as possible)
Line Voltage: 116vac
Input Voltage: 100ma
Sig Gen Freq: ~500Hz
Load: 4.0 ohm 250 watt power resistor

Power was measured just before the tubes started to clip the 
peaks of the sine wave. All tubes were purchased as matched pairs.


Manufacturer    Tube Name       Bias Voltage    Power (watts)
Phillips        7581A           -50.2           50.3
Svetlana        6L6GC           -49.7           49.0
Tesla (JJ)      6L6GC           -40.9           48.7
Sovtek          6L6WXT          -45.9           47.0
Phillips        6L6WGB          -46.9           45.6
RCA*            6L6GC           -44.3           44.5
Shuguang        6L6GC(straight) -44.0           41.7

*RCA tubes were the "blackplates".