Hi,
Putting the heaters of two 6ck4 (same brand, same construction) in series I get a difference of 0.5V between both tubes (when one gets 6.5V the other one gets 6V); the tubes are responsible for this (I switched them and voltages switched along).
-- Would the 0.5V variation in heater voltage cause a notable difference in output (one channel sounding louder than the other one, the amp is SE)?
-- Would it dramatically affect the lifespan of (the/both) tubes?
If the answer to both questions is "NO", I'll happily live with it as such; both voltages would still be in the recommended region of 6.3 +- 0.3V and I wouldn't need to spend money I don't have anyway.
As before and after; many thanks!!
Simon
Putting the heaters of two 6ck4 (same brand, same construction) in series I get a difference of 0.5V between both tubes (when one gets 6.5V the other one gets 6V); the tubes are responsible for this (I switched them and voltages switched along).
-- Would the 0.5V variation in heater voltage cause a notable difference in output (one channel sounding louder than the other one, the amp is SE)?
-- Would it dramatically affect the lifespan of (the/both) tubes?
If the answer to both questions is "NO", I'll happily live with it as such; both voltages would still be in the recommended region of 6.3 +- 0.3V and I wouldn't need to spend money I don't have anyway.
As before and after; many thanks!!
Simon
The difference can not influential it depends on schematics.
(gain, nfb, etc. etc.)
but I suggest a resistor in parallel at tube with the most greater tension,
for balancing power disipation between heater.
Datasheet of 6ck4 (GE) say 6.3 +/- 10% @ 1.25A
http://frank.pocnet.net/sheets/093/6/6CK4.pdf
that means tube can supply from 5.4 to 6.93
(gain, nfb, etc. etc.)
but I suggest a resistor in parallel at tube with the most greater tension,
for balancing power disipation between heater.
Datasheet of 6ck4 (GE) say 6.3 +/- 10% @ 1.25A
http://frank.pocnet.net/sheets/093/6/6CK4.pdf
that means tube can supply from 5.4 to 6.93
If the total current is 1.25A (from datasheet)
and Vsupply 12.5V
P1 = 1.25A * 6.5V = 8.1W
P2 = 1.25A * 6V = 7.5W
(as the light bulbs )
this is already amply accetable.
With a resistor of 100 Ohm (2W)
I = 1.28A
P1 = 7.73W with 6.32V
P2 = 7.83W with 6.15V
I suggest a resistor from 100 Ohm to 180 Ohm 2W in parallel at
tube with the most greater tension.
Also this is enough simply to verify with Pspice.
and Vsupply 12.5V
P1 = 1.25A * 6.5V = 8.1W
P2 = 1.25A * 6V = 7.5W
(as the light bulbs )
this is already amply accetable.
With a resistor of 100 Ohm (2W)
I = 1.28A
P1 = 7.73W with 6.32V
P2 = 7.83W with 6.15V
I suggest a resistor from 100 Ohm to 180 Ohm 2W in parallel at
tube with the most greater tension.
Also this is enough simply to verify with Pspice.
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