Tubes Asylum Questions about tubes and gear that glows. FAQ |
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In Reply to: Tubes rolling / balanced input posted by emile on February 12, 2004 at 10:24:37:
Emile,If you power up the amp with nothing connected to the input jacks do you here the hum? With the amp off change one tube at a time to see if this improves. The first 12ax7 is for the balanced inputs only and the amp will run fine without it if you are using unbalanced. Your amp should have a 90 to 95 dB signal to noise ratio. If it still hums use a voltmeter and check all tube voltages with the amp on, no signal.
You will find the problem. Pay attention to the bias voltage. If you have a good set of GEC KT88s that is as good as the amp will sound.
Ron-C
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Follow Ups
- Re: Tubes rolling / balanced input - Ron-C 02/13/0416:12:34 02/13/04 (1)
- Re: Tubes rolling / balanced input - Ron-C 16:15:29 02/13/04 (0)