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PS Audio PowerPlant 3 Review

Rate this AC Regenerator

  • 1. Poor (headless panther)

    Votes: 260 91.9%
  • 2. Not terrible (postman panther)

    Votes: 11 3.9%
  • 3. Fine (happy panther)

    Votes: 4 1.4%
  • 4. Great (golfing panther)

    Votes: 8 2.8%

  • Total voters
    283

amirm

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This is a review, listening tests and detailed measurements of the PS Audio Stellar Power Plant 3 AC regenerator. It is on kind loan from a member and costs US $2,499.
PS Audio Powerplant 3 Regenerator Audio Stellar AC review.jpg

There are no front panel controls other than standby/power switch on the left. To activate the MultiWave and ClearWave requires remote control which I did not have. Very bad form to not put a simple switch in the front to cycle that way. Not much to the back panel:
PS Audio Powerplant 3 Regenerator Audio Stellar AC back panel review.jpg

Shame there is no power sequencing/sense for power management.

A heavy AC cord is supplied with the unit but I got a kick out of this statement in the manual:
PS Audio Powerplant 3 Regenerator Audio Mains Cable.png


You buy an AC regenerator and it still is sensitive to what the power cord does *before* it? And significantly so? For nearly $2,500 they could not provide said improved power cord either?

Despite being rather thin, this is a hefty box clocking at nearly 40 pounds (18 Kg). Yet, max power output is only 300 watts. There is a very high price to be paid here for regeneration of high voltage AC.

PS Audio PowerPlant 3 Measurements
We start by measuring AC power as it comes out of my outlet, followed by what the PowerPlant 3 does to it:
AC Mains Input Dashboard.png

We see that in addition to the 60 Hz mains, we have a lot of harmonics that come for the ride. You can see that the tops of the AC waveform are ever so slightly deformed as well. Measurement is performed using a 100:1 attenuator so actual output is 122 volts with distortion+noise of 1.9%. Here is the output of the PowerPlant 3:

PS Audio Powerplant 3 Regenerator Audio Dashboard Measurement.png


We see a good bit of improvement in harmonic content of the AC waveform on top right. However, that is accompanied with higher noise level as we saw in PS Audio's PowerPlant 15. We can see that better if we zoom in the spectrum:

PS Audio Powerplant 3 Regenerator Audio FFT distortion and noise Measurement.png


This goes counter to company claim of noise elimination:
1670487375795.png


But distortion is definitely improved. But let's see whether that matters to our audio gear which rectifies and filters AC anyway before use. To test that, I measured the output of my 15 volt linear power supply which comes from the company GRAS:
PS Audio Powerplant 3 Regenerator Audio Dashboard Spectrum Linear Power Supply Measurement.png


There is essentially no difference between two sources of power. Reason is simple: the artifacts as you see them is created by the power supply, not from AC mains. So it doesn't matter how "dirty" the AC mains is.

What about output of our audio gear? I thought I use a low cost device that one would think needs more "help" from an AC regenerator. The volunteer was the Schiit Heretic headphone amplifier/preamplifier. Here is its dashboard when powered by Raw AC:
Schiit Heretic Preamplifier Audio Dashboard Measurement.png


Despite being fed "dirty" mains, its produces spectacularly low noise and distortion that is 5 dB better than our best case threshold of hearing. There is some power supply noise but they are incredibly low level of -140 dB (25 dB lower than threshold of hearing). Now let's power it through PS Audio PowerPlant 3:

Schiit Heretic Preamplifier Audio PS audio powerplant 3 Dashboard Measurement.png


What happened here? We took a hit in noise floor causing SINAD to drop by 2 dB. Who says we can't measure the impact of these products? We certainly can. In this case, I suspect a ground loop was created causing the increased 60 Hz mains spike. But I can't explain why the 180 Hz third harmonic has also gotten worse. Either way, we have gone backward.

PS Audio Stellar PowerPlant 3 Listening Tests
I created a chain from my RME ADI-2 Pro interface, driving Topping A90 headphone amplifier which in turn powered my Don Clark Expanse headphone. I then played some of my reference audio clips. The sound was wonderful in its detail, and dynamics with inaudible noise floor. I then switched to powering the A90 with PowerPlant 3. It took 3 to 4 seconds for the A90 to play again which is not ideal in AB tests. I thought I heard some difference but when I switched back to raw AC, I "heard" similar difference. I am confident in instant AB switching it would sound identical.

Conclusions
As with tests of other PS Audio PowerPlants (of which, I own one myself but never use), objective tests do not show any improvement in performance of audio products. Yes, the distortion is reduced but noise is increased contrary to company claims. Because first thing our audio gear does is convert AC to DC, those components are filtered anyway. Certainly you can't get a high performance audio device that is so poor as to allow input AC noise to get through it. That would be the definition of non-fidelity!

Sighted, non-blind, slow switching listening tests are bound to produce impression of audio changing but as I experienced, this is due to any change, not because the PowerPlant. Human hearing is bi-directional and dynamic so can't be relied upon outside of controlled testing.

Let's note that the company doesn't show performance of any audio device being improved with this unit. Nor any controlled listening tests. Just a bunch of marketing claims that sound plausible but as you see form the measurements, don't amount to any improved fidelity. If anything, things have been made worse in some regards due to the architecture of the newer generation PS Audio PowerPlants which are not true AC regenerators (they mix AC mains with compensation signal). As I have shown in previous reviews, my lab grade regenerator performs a lot better.

In my opinion, it is a waste of technical talent to be building such products. I see no reason to recommend PS Audio Stellar PowerPlant 3.

Edit: Video review also posted:

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As always, questions, comments, recommendations, etc. are welcome.

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Sokel

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What those MultiWave and ClearWave suppose to do?
 

solderdude

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Multiwave = flattened top sinewave (so distorted) so that reservoir caps in power amps that are significantly loaded get a bit more 'time' to replenish the voltage while limiting peak currents. As the PP limits power output by design it may help with some power amps when regenerated power is needed and poweramps are connected.

Not interesting for low power devices... in fact the powerplant is not really interesting unless one has wildly varying mains voltages that regularly dip too low for the very few not so well designed devices that rely on proper mains voltages.

Cleanwave is utter nonsensical as the magnetic field in the transformer is changing continuous so there is nothing to 'de-gauss'. A typical McClown-thought feature.
 
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martijn86

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Who says we can't measure the impact of these products? We certainly can.
The results are in aaaaand it's:
fraud

Is there an efficiency loss with these kinds of devices?
 

solderdude

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s there an efficiency loss with these kinds of devices?

Of course there is a penalty...
It draws about 18W in idle and adds some percentage (+ about up to 25W extra heat losses in the correction amplifier depending on the load)
At 300W drawn on the output it draws 345W from mains (85% efficiency at 300W)
Of course when used to power a DAC or something similar that draws something like 10W or so, you draw about 20W extra so 30W instead of 10W in which case the efficiency is rather poor due to the drawn idle power ;)
 
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JSmith

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In my opinion, it is a waste of technical talent to be building such products.
Agree completely, however I would add also a waste of finite resources too. Thanks for the thorough test, which makes it clear there is nothing "stellar" about this device at all.

1670492714802.png


1670493086715.png



JSmith
 

DSJR

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I know of one enthusiast site here in the UK, where the owner invests in all these add-ons as a matter of course. A few years back he had added a zobel network to each of the speaker terminals (speaker end - as if the one on his amp output wasn't enough), fancy pucks and weights and another maker of mains regeneration (I think this one had a display showing the distorted incoming from what I remember). I'm not criticising, but there are a good few people out there who seem to need these 'crutches' to achieve what they feel is a 'better' sound from their speakers. I did once ask him if he'd consider taking all these add-ons and fancy cables out and listening and 're-aligning' to his system 'in the raw' to try to get a feeling for the sound as supplied, but I don't think he ever did this.
 

AlexScan

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For me it's interesting to mesure a :

Furman AC-210 A E Power Conditioner​

A professional product that has been proven for a long time and which is recognized as significantly improving the sound.

Not an "Audio(idiot)phile High End" product like this PS Audio Powerplant...
 
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