Grommes LJ-6 Buzzing

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Hi,
I recently acquired a Grommes LJ-6 in great cosmetic condition. When powered up it emits a loud buzz through the speaker that is not affected by the volume control. This is not a 60 or 120 HZ hum. On tracing out the circuit I noted several poor solder joints (even 1 unsoldered), which I retouched. The buzz is still present. I suspect that the voltage amp/inverter 12ax7 is not wired properly. The 2 cathodes are tied together with a 100 ohm resistor. A bypass cap goes from the 2nd triodes cathode to ground, but is not in parallel with a resistor. Global feedback is applied directly to the cathode of the (1st) triode. The only DC path for either cathode is thru the feedback resistor and the 16 ohm tap of the output transformer. I suspect that the 2 cathodes should be tied together, and that the 100 ohm resistor should be in parallel with the bypass cap. Can anyone tell me what the correct wiring is for this? Were these ever available as kits or were they all factory wired. The wiring looks pretty sloppy. Components seem to be of good quality.
TIA,
Bob

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Topic - Grommes LJ-6 Buzzing - AstroSonic 20:34:08 11/12/06 (4)

Re: Grommes LJ-6 Buzzing - AstroSonic 06:53:39 11/15/06 (0)

Re: Grommes LJ-6 Buzzing - MIchael Samra 23:42:18 11/12/06 (2)

No, it isn't wired wrong - Russ57 05:58:13 11/13/06 (1)

Re: No, it isn't wired wrong - MIchael Samra 02:05:23 11/14/06 (0)

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