1946 Gibson BR-4 Amplifier tube question - diyAudio
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Old 4th March 2007, 03:11 AM   #1
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Frazzled's Avatar
Join Date: Apr 2004
Location: Regina, Saskatchewan
Default 1946 Gibson BR-4 Amplifier tube question

I have an amplifier that uses both a 6SL7 and a 6SN7. Can someone please outline the differences between these two tubes and why couldn't I interchange them.


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Old 4th March 2007, 06:49 PM   #2
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Location: Macedon NY
You COULD interchange them, but the phase inverter will be unbalanced - it's set up for the lower gain of the 6SN7. Bias will be wrong for both stages too, but may be close enough... note the different cathode resistors used. But expect increased distortion at the least.
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