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In the Forum: Audio Discussions
In the Thread: It’s mad, mad, mad... electricity.

Post Subject: Daisy chaining balanced transformer -> PP2000Posted by manisandher on: 7/13/2012

Romy the Cat wrote:
From what you describe I conclude that you have ground loops regardless of the PPs and the PP juts highlights the problem.

This may well be the case. I can't even remember the exact components I was using last year (a lot has changed in my system since then) but I know what I have now: PC -> DAC (via async USB) -> amps (via balanced XLR). The respective designers of the DAC and amps assure me that the signal ground is not connected to the protective earth - only the chassis of the component is. But maybe the USB ground is connected to the PE inside the PC. I don't know. But I do know that what I'm hearing is repeatable.

Incidentally, I've just tried powering the system from a few different configurations: direct from the wall socket; from the PP2000 connected to wall socket; from the PP2000 connected to a dedicated ring (with 5KVA balanced transformer and grounding rod). My order of preference is:

1) PP2000 connected to dedicated ring (with 5KVA balanced transformer and grounding rod). Very textured sound. Harmonically rich. No hint of sibilance. Very, very similar to PP2000 running from battery.

2) PP2000 connected to wall socket. No sibilance. A bit dull and flat.

3) Direct from wall socket. Easily the brightest and shiniest. Very dynamic. An immediacy that is initially appealing but that becomes a bit fatiguing with time. A bit of sibilance coming through.

I suspect the balanced transformer and grounding rod are helping to clean up the grunge that the PP2000 is inevitably putting back into the mains.

Mani.

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