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Balanced power compatabilty census

I have run across some equipment that does and does not work well with balanced AC. I thought this forum might help others, if supported. In my case, I used 5KVA transformer and one piece of gear at a time.

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If you are unfamiliar with "balanced AC", it refers to 60 volts +/- as referenced to ground and hot/neutral are 180 degrees out of phase. Normal (North America) power from outlets is 120V on hot leg only. Equi=Tech, Balanced Power Tech. and DIY projects convert single phase to dual phase with the "promise" of reduced noise. In some cases, sonic improvemnt can be more than just reduced noise. In other cases, the grounding scheme of the equipment may not be compatible. Don't jump to conclusions that because one experience or model worked or didn't, that it reflects on the brand or type.
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Genesis Stealth amp did not work properly but I suspect problem is due to active x-over.

Plinius SA100 mk3 worked better but no better than simple isolation.

Sonic Frontiers SFL-2 loved it and had immediately noticeable improvement.

Manley Snappers sounded compressed with balanced AC. Odd for differential amp.

I have yet to try with sources which have separate isolation.

Does anyone else have have positive or negative reports?
ngjockey
nsgarch's avatar
nsgarch
2,524 posts
 
My front end (Levinson preamp and phono preamp) and sources (Wadia CDT+DAC, Goldmund TT, Technics FM, Nak cassette) are powered by balanced power (Exactpower SP-15A) and sound better than ever before.

However, FWIW, I should disclose a couple of things that were done at the same time as adding the balanced power unit:

The balanced power unit itself gets its power from an Exactpower EP-15A power regenerator unit (which also powers the Levinson amp, Martin Logan stats and sub).

Also, all the power cords were upgraded at the same time, to Purist Dominus/Venustas, Aural Thrills, Audio Metallurgy, and a couple XLOs.

rgd
656 posts
 
Never tried my big amp on it as the manufacturer advises against it. Cdp/transport and DAC seems to work well but tubed preamp does not - severely chokes it.
john_tracy
341 posts
 
All of my system is plugged into an Equi-tech 2Q and everything loves it. System is very quiet. No ground loops. All grounds referenced off CT of the 2Q. Front end: K&K phono pre (kit), Cary CD-308 (used as transport), RAKK DAC (K&K Audio kit), Fisher FM-100b (modified). Raleigh Audio line stage (kit, K&K Audio) and currently a restored Eico HF-89 (gutted and rebuilt and modded by me). The line stage is transformer coupled input and output using Lundahl amorphous core tannies. It's a differential parafeed design. The phono pre has a SE parafeed output using same Lundahl iron as does the RAKK DAC which uses a transformer and resistor to provide passive I/V conversion. I think having the galvanic isolation provided by all the transformer coupling can reduce the chance of a bad interaction; no ground currents on the interconnects. One of the mods on the Fisher was to rewire it for a three wire IEC connector.
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