Help with tracking down hummm? -long

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I have an Audio Note DAC 1.1 w/new 1.2 power supply. I did some mods which endtailed removing the regulator tubes in the ps and replacing them with a large electrolytic and bypass cap to get more voltage as I had decided on a 6CG7 tube in the analog and it needed the extra valtage to gett he curves right. I also installed a choke between the ps and analog and split the power to both sides of the tube with diode,cap & bypass on each channel.
All was getting brilliant sonically and I was dialing in the resistor values over a couple weeks when I accidentally discharged the new bypass (.01) cap on the p.s. right at the HV lead. The caps sparked at the screw I was removing which was beside the cap.
I immediately checked all the voltages and they were spot on. Then I played it to see if there was any damage. The unit sounded like it was under water and had a humm. I changed the bypass caps and all the sound came back although I still had a nasty humm and peak distortion.
In frustration I sent the digital board back to Audio Note along with the p.s. Mike said he was sure I damaged the digital board. He called me and said both boards were ok and sent them back.
When I reassembled the DAC I still had the same problems. Thinking it had to be the analog board I went through everything swapped parts, bypassed caps - the works. No change.
I don't have a scope and sending it to AN to be told nothing was wrong was very costly.
Does anyone have any ideas?
Thanks for reading this. This board is always a savoir. I know this was a long explanation, but how can a person learn without asking and explaining the situation.

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Topic - Help with tracking down hummm? -long - BTE 15:56:29 03/31/02 (0)

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