manisandher wrote:

I don't have a scope, so can't measure the output of my particular unit.

manisandher wrote:

However, if I were to guess, I would say that my unit probably falls alongside your #2 unit. When run from AC, the bass disappears and the sound becomes bright and edgy, to the point of being unlistenable. From battery though, the sound is full and harmonically rich - very, very nice indeed. Quite frankly, you would have to be deaf not to be able to hear the difference.

manisandher wrote:

Having said that, when I first received my unit, I had it connected to the system in my study. During an email exchange, I agreed with Bob Rappaport that there seemed to be no difference in sound between AC and battery…

manisandher wrote:

I'm not sure, but perhaps if more PP2000 owners voice their opinions, PP will stop living in denial.

Romy the Cat wrote:

A few words before I lay down the facts. Over the last week I got a number of signals from PurePower that I shall not defame their products. Their marketing director Bob Rapoport – a certifiable idiots – informed me that my finding about PurePower 2000 are “based on sheer fantasy”, that he “would bet that in a double blind AB test I would never know the difference” and that I shall “take down the entire thread about PurePower from your blog” because it “this is a hobby to you, but its my livelihood”.  Their technical people dodge my calls. They claims that they here no difference of any kind between old and new units and between PP2000 running from AC and buttery.  This is very alarming and my odder to demonstrate it to them, even more - my proposal to give my facility and my engineering rescores for their disposal to find the problem – all left without answer. The PurePower owner has, who looks like offsite now days, has more rational position. He also is concern about me “defaming” his company product. He diplomatically implies that “we are interested is solving your problem”, which makes me surprised: my problems? Really? The whole point is that the problem I am experiencing is not my problems but purely the PurePower, or more accurately the problems with PurePower 2000 operation. Rgs, Romy the Cat

"I appreciate audio devices that instead of demonstrating their own qualities, force you to think about sound. The new PurePower 2000 is turning to be such a device. I have so many ideas and so many thoughts with the sound the 2000 produces that I truly surprised myself. Today, spending many hours with my new regenerator and listening to music, I could not hold myself from laughing as many times I caught myself acknowledging that this or that aspect of the sound was exactly how I always insisted it should be. It was like being an orphan and suddenly discovering one's own parents

Somehow the PP2000 surgically removes all negative manifestations that are typically associated with bad electricity but keeps everything else absolutely un-affected.

After spending those 4 days with the PurePower 2000, I suggest that they adopt my proposal for a new slogan: "We do not 'f ***-up' your Sound." As far as my familiarity with power treatment devices is concerned, I know of no other power company or product that might be entitled to use this slogan.

It looks like the PurePower 2000 resolves the problem with electricity once and for good..."

 Roman Bessnow, www.romythecat.com

The above is lifted from their page entitled 'Reviews and Opinions' So we have here, for our common delectation this most debased sort of modern corporate entity, the type of vulture that will prowl the web looking for crumbs of praise from all possible parties, exploit these to serve its most undiluted commercial interests, but threaten legal action the moment one dares say something disparaging about the company's products, even if backed up by a desire to help them get it right. It makes my soul shudder at the sheer gall of it. I cannot tell you how nauseous this kind of hypocritical behaviour makes me feel and how I would love to see PurePowerAPS' lawyers cringe under the scrutiny of any court. The best lube in the world would not protect them from getting what will be the eventual and sure outcome of such a case. From what you write about Bob Rappaport above, it sounds as if this might well suit the gentleman's inclinations.

I read their marketing spiel, their technical claims and their product literature, and whilst it is obvious the company makes many claims of utterly reliable performance and exemplary service, it is clear there are several documented instances where its quality control failed and service was less than exemplary. Actually the service provided by PurePower is so below par that how they have managed to stay around is a complete mystery to me. They fully deserve to vanish without a trace and I can only wish there was another product from a more responsive company, that genuinely understood something about sound, that would do the job.

Romy, this is science and PP does not have a monopoly over a perfectly capable solution to our mains problems. It is only a matter of time before this other solution is found. It is a shame that to some extent you got 'captured,' whether you will openly admit to it or not, as you clearly needed their assistance to sort the flaws with your units. I hope somehow you find your solution soon whether from PP or elsewhere so you can vent your spleen freely about this utterly miserable little company.

Regards
Rakesh

Romy the Cat wrote:

PurePower do not need to collect opinions, including from me. The need to produce a product that has default operational sound and the made of the product shall be assurance of default, repeatable and predictable result.

oxric wrote:

I read their marketing spiel, their technical claims and their product literature, and whilst it is obvious the company makes many claims of utterly reliable performance and exemplary service, it is clear there are several documented instances where its quality control failed and service was less than exemplary. Actually the service provided by PurePower is so below par that how they have managed to stay around is a complete mystery to me. They fully deserve to vanish without a trace and I can only wish there was another product from a more responsive company, that genuinely understood something about sound, that would do the job. Romy, this is science and PP does not have a monopoly over a perfectly capable solution to our mains problems. It is only a matter of time before this other solution is found. It is a shame that to some extent you got 'captured,' whether you will openly admit to it or not, as you clearly needed their assistance to sort the flaws with your units. I hope somehow you find your solution soon whether from PP or elsewhere so you can vent your spleen freely about this utterly miserable little company.

Rakesh, you sound too sane but I still disagree with you. I even disagree with myself while I am disagreeing with you but the rational for my disagreeing I think deserved to be expressed.

I have absolutely no interest or concern about PurePower or make judgment about them. I care about performance of the PP2000, primary as its performance in my home but there are secondary, less important reasons as well. Unfortunately (and this in ONLY in my eyes) the PP does have a monopoly over a perfectly capable solutions to my mains problems. It hard to explain, Rakesh, but if you spend as many years as I did to fight electricity and if you heard the sound of properly operating PP2000 (the way how my  PP2000 was for the last year or today PP2000 from buttery) then you would feel that it was “it”. Sure, PurePower has no monopoly but from what I have seen PurePower is the closest from anybody else to a perfect sound from their regenerators. Of course I did explore a lot of different manufactures who does the similar and was looking if I can jump in their wagon.  I feel that PurePower are the closest to the “promised land”.

There is something else. I did write it many time that I do not think that PurePower know what they do and that sonic results they get are accidental. The problem is that no one know what is going on with electricity and it is a very complex subject. PurePower need to invest some efforts to investigate what is going on wrong but I do not think that they have recourses to do it. I have a number of very serious engineers on my end who observe the progress and who laugh on the situation and they say that this BS is possible only in Hi-Fi…

I do not know where we go from here. I have some clear ideas and some very specific experiments that need to be done with PP2000 but I would like the test were endorsed and underwritten by PurePower. When I spoke with this technical person I am not sure he understood what I was taking about and as now it looks like they “understaffed to handle your phone calls”.  I still would like PurePower to get PP2000 to the point what it will be useful, useful by me. I am not manisandher and I will not use the PP2000 from buttery only – I find it ridicules.  So, I got hooked on the sound that PP2000 might deliver – I admit it and I do admit that my masochism is voluntary. Trust me however; I know what I do even if I do wrong things.

At present time the concern need to be not about my physiological profile and not about PurePower BBB reputation but about the health of the PP2000 unit. The PurePower does not express about it as much concern as I do – that is the problem.

Jorge wrote:

"I do not know where we go from here. I have some clear ideas and some very specific experiments that need to be done with PP2000 but I would like the test were endorsed and underwritten by PurePower" "I have a number of very serious engineers on my end who observe the progress and who laugh on the situation and they say that this BS is possible only in Hi-Fi…" I see a simple solution, If PurePower doesnt know what to look for, you go ahead and FIX the problem, with your engineers on your end,  then you can pay for all the costs of THE FIX selling your own "Romyzed PurePower",  This is a win-win solution:  PurePower continues to sell their their systems....to you, and you sell them for an overprice after applying this FIX. You dont even have to get your hands dirty,  get in touch with one or more of those modders that "modify" Cd Players, lots of them around to have a pick, and let them do the FIX to the units for you and even send them off....you just collect the money! Or you can just fix YOUR own PP2000 and leave us to our batteries and caps and coils  ;-)

OK, here are my thoughts for today. Below is a very simplified schematic of Pure Power 2000 regenerator.  I do not know if it is, but I think that it is how it works. I do not think that it is different from any other on-line generator. At the link below under the bottom of the first page is a typical operation of such units:

http://www.armspower.com/Products/Powerware/Powerware9330/Powerware9330%20Double%20Conversion%20Online%20Toplogy.pdf

If to simplify everything for PP2000 case then we end up with this:

What we know about the new revision of PP2000 – we know that powering from battery the unit works fine. That means that the yellow past of my diagram are out of suspicion for bad operation. However, when we engage the white elements of my diagram then sound turn shit and it looks like it turn shit not equally on all units. So, I think it would be reasonable to talk about some kind interference that input stages inflict to outputs. What kind interference it might be and the most important how it get propagated to output stages? I think it might be via grounds, air or via wires.  I have no control and no way to test grounds and air theories – this what Pure Power company must do nowadays but I think I can make some tests about the wires propagation interference.

The only wide how the white and yellow sections of PP2000 are connected is the battery (it would be nice if Pure Power would confirm it). So, let see what battery does what unit runs from DC and from AC

The first part of the image the PP2000 runs unit from itself and the second one is what AC is coming in. We see that some AC noise is coming on the negative side what the charger activated. You can get the frequency of the noise – it is 20uSec per square. Also the amplitude of the noise is very low – it is 0.02V per square, so in my mind the charger might works fine. I do not think that exist any higher frequency noise (I use slow 100MHz scope) as this all switching devised that works at 20-30kHz and would be not transparent for any noise over 10-15kHz. So, the interference between AC and DC operation is very low, not to mention that after first DC to DC up-converter it most likely shunted with a large cap that would ground all noise and interference. However, all low voltage logic (and it is a LOT and complex logic) is driven directly from buttery and who knows, might be this minute noise on the negative side makes the low voltage logic to go crazy what it feels it. So, we need to equalize the pane and to make the low voltage logic to see DC identically as it sees when the init runs from buttery. Then, if we still have the problem with sound it will be 100% assurance that the very little noise that butteries get during AC operation is not the problem responsible for sound.

I wish the Pure Power be with me on it as it looks like it is my own problem, anyhow…. My guys advised me to shunt the PP2000 butteries by a pre-charged, large capacitor with a series choke. They explained that butteries have high internal impedance at HF and my external HF filter will deal with all noise.  I need to buy 250,000uF at 100V and try to make the experiment. It would be great if that will be the reason as to address anything else it need to be look on the PP2000 motherboard – something that I do not do. BTW, it would be great if Pure Power make this as the have all equipment setup for those experiments… But it is only if they want results….

Romy the Cat wrote:

The first part of the image the PP2000 runs unit from itself and the second one is what AC is coming in. We see that some AC noise is coming on the negative side what the charger activated. You can get the frequency of the noise – it is 20uSec per square. Also the amplitude of the noise is very low – it is 0.02V per square, so in my mind the charger might works fine. I do not think that exist any higher frequency noise (I use slow 100MHz scope) as this all switching devised that works at 20-30kHz and would be not transparent for any noise over 10-15kHz. So, the interference between AC and DC operation is very low, not to mention that after first DC to DC up-converter it most likely shunted with a large cap that would ground all noise and interference. The Cat

I usually do not cruse across DIY forums unless someone folks about me. Here it was - at some Russian DIY site they translated my article “6C33C survival guide” that made me to see what they have in there. One article from their site attracted my attention. It was from spring of 2010 by somebody called AlexD. He described how he built his 3-stages PP amps with 2N23P-6E6P-6С41С. I do not know if I like this amp but what this amp has interesting was the power supply – he use pulse power supply from computers but hand rebuilt. The article in Russian and to see the articles you need to be registered (stupid thing to do in my view) but the images are clickable and can get bigger even for guests.

http://datagor.ru/amplifiers/tubes/1209-moshhnyjj-rr-na-6s41s-s-pitaniem-ot-impulsnogo-bp..html

I do not know if I am a fan of Pulse Power Supply but in context of what I am going now with PurePower it made me to think. I do not know why a properly working PP2000 produces such a positive sonic effect comparing to the linear regenerators that out much less distortions and noise.  So, frankly I would not mind to hear an amp with Pulse Power Supply built explicitly for a given amp. It might be interesting.

You see. We use a regenerators like PP2000 or PS Audio’s Power Plant to reshape the sinewave and we are under presumption that crooked wave is not good. Then we give to amp a perfect wave and it is still not good sounding – think about Avicenna or Power Plant regenerators. In contrary the older version of PP2000 did sound very well despite that it had much higher distortions of sinewave. So, let assume just for mental exercises that the quality of sound is absolutely independent from the sinewave deformation. Let also assume that not the fact of deformation but the outcomes of deformation affect sound. For instance if sinewave is clipped – a common problem with AC lines then the act of clipping itself injects a huge amount of HF noise into the line. The noise is very higher harmonics of unclipped signal, so we have 4th, 11th, 23th, 34th harmonics, they are way attenuated but they are there and they are in ULF…. Then we have Pulse Power Supply…

According to the Nyquist–Shannon-Kotelnikov sampling law:

http://en.wikipedia.org/wiki/Nyquist%E2%80%93Shannon_sampling_theorem

any switching devise is able to reproduce no higher frequency then a half of sampling rate. It means that the device like PurePower PP2000 that runs let sat at 20kHz of sampling rate is absolutely immune to any line noise that is higher than 10KHz. Any higher frequency noise just falls between the pulses of the switching device. So, purely hypothetically: if the quietly of sound from a properly operating PP2000 derives from the fact that it is pulse but not from the reshape sinusoid then why a Pulse Power Supply on SET amp with no regeneration would not do the same trick?

What I would like to see is somebody makes a SET amp with linear PS and then substitutes it with Pulse PS. Of cause it might be zillion reasons why ether linear PS or Pulse PS would not sound good but I would like to hear not the absolute performance but to hear if the change in sound would be in the SAME strategic direction as the properly operating PP2000 takes sound to. At this point I truly know what to look for in sound and how identify the PP2000-like contribution to sound. So, if someone in New England would accommodate Pulse Power Supply for your SET then let me know and I would like to hear it “before” and “after”.

Romy the Cat wrote:

I got a contact from PurePower this morning and they requested some times to look into what is going on. It was not exactly pleasant that they took my behavior as my personal attack against them – it was absolutely not my intention and I have no personal animosity of any kind toward to PurePower. I might hate their marketing guy but this is my good a healthy hate of any marketing cockroaches Anyway, from the conversation I have it was explainable why I felt abandoned with my little “fictional” problem.  PurePower needs some time to come back on-online.  Lets hope that they/we will be able to find what is the problem and return the PP2000 to where it shell be. I will retune to this subject next week

Romy the Cat wrote:

Romy the Cat wrote: I got a contact from PurePower this morning and they requested some times to look into what is going on. It was not exactly pleasant that they took my behavior as my personal attack against them – it was absolutely not my intention and I have no personal animosity of any kind toward to PurePower. I might hate their marketing guy but this is my good a healthy hate of any marketing cockroaches Anyway, from the conversation I have it was explainable why I felt abandoned with my little “fictional” problem.  PurePower needs some time to come back on-online.  Lets hope that they/we will be able to find what is the problem and return the PP2000 to where it shell be. I will retune to this subject next week It looks like PurePower did find something in my regenerator and they are very confident that they will fix it.  Sure, I would like it never happen with my units but it is what it is. The PurePower is so confident the they know what the problem is that give me 110% that whatever they will fix will bring sound back what it used to be with my old unit. This opportunity made me literary horny as after a year (actually 2 years, from December of 2008) of absolutely discarding electricity problems and laughing on the people who do not use PP2000 I felt absolutely fucked by losing my regenerators. They promise that I get my first unit back before the end of the year – I will handcraft myself to the mail box. If the new regenerators will sound good then the only thing that would make me absolutely happy would be if PurePower send me that cut off ears of their stupid sales pimp - Bob Rappaport. I will dry them out, put in me herbarium and then will use them as my next Halloween costume – I will be dressed as a Deaf Idiot. Rgs, Romy the Cat

Young Skywalker wrote:

I have been intently following this thread for many years and this recent update is very encouraging. I hope that the Pure Power people can deliver on their promise and that the sonic outcome meets with your objectives. Please do share the root of the problem along with the solution so that other recent Pure Power users might benefit from your harrowing experience. Regards,YS

Skywalker,

I am afraid that that I am not a spoke person for the company and the root of the problem along with the solutions for others is not something that I am willing to discuss. I have no idea what problem other might have and if they have any. My statue of a “public figure” has some self-imposed restrictions. I do not practice a consumer advocacy or investigative journalism in audio. The “truth” in audio interests me as long as it affects myself – I very much individualist or probably more accurately to say audio egocentric egotist. My PP2000 stopped working and it spelt disaster in my little made-up world as I have spent so much time and efforts until I found the PurePower device. My fear was very genuine as I thought I need to find another solution and it was not in my plans. I even made a call to people I know asking to build my own regenerator, identical to PP2000.

I do not know what went wrong with my 3 PP2000. The PurePower technical folks did give me a reason but frankly I do not particularly believe into those reasons and in all explanations they gave me, also do not forget that PurePower tell me only what they want to tell me. But what would I do care – tha they are confident that they know the reasons and if they assure me that the unit will be the “magic box again” - what else do I need to care? Theoretically the things happens, I just wish they did not BS me for 2 weeks insisting that the wrong sound from PP2000 was the result of my hallucinations or was course my sophomoric use of the unit. Still, they did find the problem and the feel very comfortably that it will be addressed. I think the fixed unit will be coming after Xmas, I think at this point I am obligated to report the result. I assure you that the report will be absolutely objective.

In this whole story there is a sad part. The new PP2000 did sound bad despite of fine measurement of the wave. If I get the fixed PP2000 and if it sounds fine then most likely it will be producing the same wave. So, the sound quality does not derive from the distortion of the fundamental but from something else. I afraid that the analyse, experimentation and looking deeper into this “something else” is even more important than to get the PP2000 fixed. I would LOVE to learns about that “something else” and I would like to see if that “something else algorithm” might be applied to not-regenerated AC and to a bad wave.  My presumption that it might happen that in order to have good Sound the regeneration is not necessary at all. I was trying to arouse the PurePower people to this thinking but I did not feel that they are interested to look into this deeper, I am not sure they understand the whole idea.

Anyhow, as the PP2000 will be fixed I do not have any itch to look into the problem myself and to search for that “something else” or for the philosophers' stone of electricity. I will not know the truth why those things work but do you want to be right or to be happy? I am kind of getting old to be right nowadays I just look forward to be a “user” and to be happy. Hey, I did all that a sane person shall do, I even got 3 of PP2000 in to assure that they will be available for me in future if US decare war to Canada and will ban all Canadian goods…

Got today a December 2010 PS Audio Newsletter with an announcement from Paul McGowan:

“…So, in January 2011, we will release one of our secret projects that have been in the works for two years now, the PerfectWave P5 and P10 Power Plants.  Not necessarily a replacement for the venerable PPP, but two new additions to an already powerful (pun intended) AC power line.

Both the P5 and the P10 are completely redesigned from the ground up to be the best and most reliable performers we have ever built.  There’s a whole host of features and functions you’ve been asking for, all bundled up into these great designs.  Certainly a major upgrade step from the PPP, so if you’re looking to kick your system up a notch or two, this is the ticket.  A P5 or P10, compared to any other power conditioner in the world, just stomps them.

 Because this is just a sneak peek at these new products, we’re not releasing any more information than what we are presenting here to our Newsletter readers.  The full story in January.

The P5, which is the smaller of the two, is housed in a gorgeous matching PerfectWave chassis and is capable of a continuous 1000 watts of power, with peaks up to 1200 watts.  It has 4 isolated and switched zones and one of the zones is specially designed and optimized for high power applications like big power amplifiers.

Inside the P5 we have twice the number of capacitors for greater energy storage, ten times lower output impedance through a four-fold increase in output devices (compared to the PPP).  Better dynamics, blacker blacks, and extended voltage range are all waiting for new P5 owners.

From the front panel, there’s an amazing new touch screen controller for both models.

 With the touch screen you can now fine tune your unit’s output voltage, switch individual zones on and off with a touch of your finger, measure the wattage being delivered and used, the THD and voltage in and out.  But here’s a real kicker: we added an oscilloscope to the touch screen!  Now, for the first time, you can actually see the incoming and outgoing waveforms on your line.  So, not only can you measure the distortion on the line, you can see it.

And because the new PerfectWave Power Plants reduce distortion over 10 times, we will show you the residual or the difference between what’s coming in and what’s going out.  I can’t wait for you to see this in action.  It’s freaking awesome.  Wait till you see what the difference between incoming and outgoing power looks like on a scope.  It’s downright frightening - and keep in mind, no power conditioner can fix any of these problems.  Only a Power Plant can.

But wait, we haven’t yet written about the P10. Housed in a beautifully stretched PerfectWave chassis (same footprint, just taller) which is, incidentally, the same chassis as we’ll put our new power amplifier in - the P10 is a real gem to behold.  Massive heat sinks along the sides cool without fans and this beast weighs in at more than 65 pounds.  Truly a force to be reckoned with.

Performance wise, it’s a stunning achievement.  1200 continuous watts of pure sine wave power and 1500 peak watts handle just about anything you can throw at this AC regenerator.  It features 5 zones, two of which are optimized for high current applications, each switchable from the front panel touch screen which has all the cool features I just mentioned above.

Inside , we have twice the magnetics, twice the capacitive energy storage, four times the output devices of the Premier and this baby just rocks.

Both the 5 and 10 have what we like to refer to as extended voltage range as well.  This feature solves one of the problems we’ve had with the Premiers: over voltage in some areas.  Sure, the PPP can protect your equipment, but in some cases, the PPP itself could fail or have worse performance when too large a voltage swing happened.

Now, with the 5 and 10, we can get crazy voltages without any penalties.  For example, in places like Australia where the nominal voltage is 240 volts, we see swings up to 280!  The PPP could not handle such a big swing, but the new PerfectWave Premiers can, no sweat.

 Lastly, there are a number of cool internet based features that give the new Power Plants green features as well as monitoring from a web page.  Both the P5 and P10 connect to our Globalnet servers and allow you to access them over the internet.  Just go to your unit’s web page, schedule the PerfectWave Power Plant to turn equipment (or even itself) on or off according to any schedule you want and everything is handled.

This new addition to the Power Plant line is very exciting and the culmination of two years of engineering.  Both models will go on sale next month, January 2011.  For those of you wishing to step up to a PerfectWave Premier, we will have an aggressive trade up program available worldwide to assist you in this.

Get excited.  It’s worth it.

Pricing is different depending on the voltage because of the different magnetics required.  Suggested retail for the P5 is $2999 for 100 to 120 volt units and $3,499 for 230 volt units.  The P10 is $4499 for 100 to 120 volt units and $4999 for 230 volt devices.

We’ll announce the official worldwide trade up program in the January Newsletter.”

Well, it is hard predict what it will be. From what Paul describes it look like it will be the same old PP but with new bells and whistles. The interns ass is not particularly bad, it is nice to tonal to own network and turn the amps on to make sure the they are warmed 30-40 minutes before you airbed. Sure it will have a remote control and remote controlled bypass switch. It looks like the topology is the same - class A/B amp. That is good that PS Audio stuck within it. We need a diversity of approaches. Paul said that his new regenerators are “completely redesigned from the ground up”, well why not to gullible and to believe. I do not see why the new Power Plants shell sound better then old one as PS Audio never acknowledge any sound problem with old Power Plants but let to have open mind about it. I still have one PS Audio Power Plants and I might trade it up of the new Power Plants sound acceptable.

If somebody near Boston get the new Power Plants then bring them in for an evening and we see how the new generation of Power Plants do against my (hopefully fixed) Purepower PP2000

Meiko41 wrote:

Dear Romy, You said that PS Audio never acknowledged any sound problem with old PP. Did you ever identify something "technically wrong" in the sinewave that a PPP outputs that peoples from PS could work on ? May be I miss your report on that point but the only comment I can remember is that although the signal is very good (at least much better than a Purepower), it does not sound as you would like it to be.

Oh no, absolutely not. There was absolutely nothing "technically wrong" with the sinewave that a PS Audio Power Plant outputted. In fact the sine wave was exemplary, regardless the load I tried. The problem was with sound, with the fact that the Power Plant did not sound as good as “good sounding” generator shall sound.  You see, we are under impressions that bad sound come ONLY from the distortion of sinewave but it is not truly the case. BTW, I did encouraged Paul McGowan 4 years back when I first heard the PurePower to go class D but he refused as he felt (I think ) that this niche market was already taken. I was trying to convince him at that time that his Power Plants sonically way more inferior to PurePower PP1050 but he decided to be where he would like to be. Well, he has his full rights to do whatever makes him happy.

I think he was fool then and his is fooling himself now.  In a way it is good and bad thing that PS Audio did not move toward to class D generators years back. Good is in the fact that somebody keep putrefying the class A/B regenerators, who knows might be they come up with something good eventually. Bad is in the fact that PurePower has no competition neither in design, nor in Sound. To the best of my knowledge PurePower s the only company the offer class D audio regenerators. If we had 5 companies like PurePower competing for the same very small market then we would have much more exiting products with very rapid development-to-shelf cycle.

I think it is about money. PurePower is a small company that most likely adopted an existing UPS devise and tweaked it up to the point to make it suitable for audio needs. It is not designed from ground up for audio needs in my view and in view of some people with whom I consulted. Those UPS devised are design for cheap assembly and extremely confusing layout where all elements of the circuit sit atop of each other. When showed the PurePower layout to my engineers who deal with switching devises then they informed me that PurePower shall be 4 times smaller, must be completely differently arranged internally and shall out as stable sinewave as PPP goes. 

I very much not criticizing PurePower I just say that with absence of competition they can do whatever they want. If tomorrow APC , HP, Fluke or Tektronix with their billions dollars revenue and thousands good engineers on payroll who trains to deal with mission-critical systems would heir new CO who happen to be audio guy then those companies would come up with instrumental regenerator against which Paul McGowan would calibrate his distortion analyzer.

Again, we still do not know if we need all of it as we do not know who one power devise sound good and why another sound bad. We do know why in some cased the electricity is very bad for audio. We can predict what it will be bad. The problem that I am not sure that we can predict what electricity will be good for Sound. Something that PurePower does make it good. As I told before – I do not think that PurePower people know what it is…

Paul S wrote:

I suppose there are the usual strong strictures against it, but has anyone tried lifting the (3rd wire) ground only during wall-powered operation?  Best results, whatever that might mean, would require a "dedicated home run" for the neutral wire.

Romy the Cat wrote:

To my surprise, pleasure and horror they all turned out to be absolutely differently sounding. PP2000 #1. This one that has been using all week - the updated my old PP2000 (new version of motherboard). This one the absolutely worst – large amount of unpleasant noise, hugely homogenized tone, no bass, no anything – just disaster. It runs fine on batteries with fine sound. This unit I did some very basic measurement and they were fine. PP2000 #2. I do not get this unit. It does much less, practically no noise and no homogenization. It has some bass and in a way a clear bass. But something is very wrong in this sound, I can’t figure out what. It runs not identical but similar from buttery. I have no idea what is wrong with it, I did not measure it and I prefer do not use it. PP2000 #3. This is a lucky bustard.  It has practically no noise, no homogenization and it highlights the tones almost as good as my old PP2000 did. It has that precision, discrimination and authority in tonal and dynamic accents for which I so love the PP2000. It has a bit too shallow very lower bass and a bit general brightness that I did not remember the old unit had. It is not a lot but it there. It runs from buttery a very slightly better – picking the lower bass in partially getting rid of the business at HF.  The way how this unit sound from butteries is how the properly functioning PP2000 shall sound. The PP2000 #3 I think is useable, the first two units I am afraid not. I would like to have my old PP2000 back then I will have 2 find sounding PP2000 hopefully if PurePower will fix whatever is wrong with the new revision then I will get my third unit. Since the all so not even it is possible that the secret in some kind of calibration or adjustment that might be not done properly at PurePower. I did ask multiple times before they shipped them if the tested them and they told that they did. I did not measure my PP2000 #2 and PP2000 #3 but even my worst PP2000 (#1) measures fine. So, go figures that are responsible for sound in those units. If PurePower have more interest about subject of good sound and how to get it predictable then the situation might be a great opportunity to learn about it. Unfortunately it looks that PurePower more care about damage management. Boring and contra-productive. The Cat