Paul S wrote:

It surprises me if you wish to do away with the battery. Or, perhaps a unit could be offered "less battery", which the purchaser/user could add on his/her own. This would "solve" the logistical problems (and the expense) of shchlepping batteries, at least for the "manufacturer"/sales/service people. Surely, anyone could follow instructions and get a decent battery (or batteries) on his/her own.

Remind you that in properly operating PP it shall not be negligible difference if the unit run from battery or from wall outlet. Sine I do not know why PP sound as good as it is (when it works properly) I can only speculate what the presence of battery would do and how it might impact sound quality.  Presumably it might not affect sound at all properly operating PP would be working perfectly fine with no battery but with large capacitor tank instead of battery. For sure I would not be making those experiments with my PP. It is kind of shame as if PP would back me up with this experiment then they would be able to get rid 2/3 of the regenerator  along with charging circuitry - in my estimation the most problematic in the unit. If I design my own regenerator then I would for sure put the requirement do have any battery.

Romy the Cat wrote:

That is a whole point: the shape of the sinusoid and consequential harmonic distortions are not being the decisive factor that responsible for better sound. It is sad that neither PP owners nor we the users after years of using PP still have no idea what in this regenerator makes it to sound so good.

miab wrote:

I have not seen it mentioned but I might of missed it. The PurePower absolutely demands shielded interconnects especially between preamp and amp in my experience. No matter how careful I route the cables, I was getting noise or buzzing from the speakers. Exactly as described by many on the net. Only shielded cables were successful to stop this. This is with a Placette passive. On my second system with Purepower, the ground lift on my Placette active sorted the noise out to absolute silence with proper care in routing wires. I just mention this in case others need ideas in diagnosing buzzing that I so often hear of.

Romy the Cat wrote:

First of all I need to admit that I do not believe to people who claim that Purepower produces noise. My units are completely silent and I know other people who have completely silent Purepowers. I have no doubts that the people who report noise do have nose but I attribute the nose to their lock of competence to deal with ground loops. There is another issue – no matter now inapt Purepower folks are and how negligent their assembly and testing I do not think that they can do anything that would make the unit to have the noise while it maintaining in and out grounds and while producing proper wave.

Paul S wrote:

Perhaps the PP in the circuit raised the residual current on the neutral and/or ground line(s)? ...shielding might still help with "hum" if the shielding was grounded in a way that dropped ground resistance/residual current on the problematic line. This notion still supposes it's a "ground loop" problem; but it also "explains" the roles of the PP and the shielding in "causing" and "solving" a hum problem.  Paul S

miab wrote:

Adrian, can you confirm whether you were using cable with shielding or without? Like you I had the buzzing go away when on battery or without PP2000 in system. It became dead silent. Then with PP2000 back in system there was buzzing. I went to all shielded cabling with PP2000 in system and it went silent again. I attributed it to ground loops not EMI.

drdna wrote:

Romy the Cat wrote: First of all I need to admit that I do not believe to people who claim that Purepower produces noise. My units are completely silent and I know other people who have completely silent Purepowers. I have no doubts that the people who report noise do have nose but I attribute the nose to their lock of competence to deal with ground loops. There is another issue – no matter now inapt Purepower folks are and how negligent their assembly and testing I do not think that they can do anything that would make the unit to have the noise while it maintaining in and out grounds and while producing proper wave. If you recall when I had in my possession my PP2000, before I sent it for repairs never to be returned, I did have some buzzing. Now my system is otherwise silent, and while group loops are always a concern, I do not think I was at fault.  As you recall, the buzz vanished when the PP2000 was unplugged and run in battery mode. Since everything was plugged into the PP2000, nothing else about the circuit was changed. The only change was basically to remove the part of the circuit internal to the PP2000 which acts to process power from the wall outlet. So, I came to conclusion that there must be faulty ground loop wiring defect inside the PP2000. The idea of faulty assembly was further suspected when the PP2000 failed outright. Of course, we will never know what actually was the issue, since when I sent it back for repairs, it disappeared and I never received a replacement.