Powerplant peak current and noise filtering Capability

@Paul or @rower30 or any one from psaudio or any community member who can chime in

i have a few questions on the capability of the psaudio power plants

  1. The powerplant say p12 or p15 or p20, does it have the capability to provide more peak current compared to a wall outlet?
  • asking about this because since the regen involves AC-DC-AC , does the power plant have more storage capacitors to augment for peak and transient current requirements say for a power amp needs?
  1. does powerplant have any noise filtering capability (common mode, differential noise, removing dc noise from AC)? if so what stage these filtering are applied?

  2. is there a possibility of any kind of noise to be able to get thru to the final AC output?
    theoretically AC to DC to AC should completely eliminate and isolate and should be the best strategy for this but i want to know if this is true practically as well

  3. if i have an amp say which does 450w rms in 4 ohms, can this amp be plugged to p20 high current , where p20 is connected to a 15 amp circuit? in this scenario would there be any loss of dynamics or any problem is keeping with the peak and transient current demands. for example p20 spec says it can provide 70 amps peak .would this spec be for a 20a circuit.if so how much would be the peak current if it is connected to a 15A circuit? and also for how much time in milliseconds can this peak be supplied by the powerplant?

  4. considering the power regen and power cleanup capabilities that powerplant provides , does that mean that it eliminates the need for very high quality & high priced power cables, meaning these cables will have less impact,since powerplant will do a lot of heavy lifting already?

The P20 needs a 20A outlet to reach FULL VA power. Into a 15A outlet it is really a P15 VA, and the manual explains that. The switchable IEC plug alloes you to safely use it on either a 15A or 20A circuit. SLIDE the cover to allow the proper IEC input to the P20 from the wall outlet.

Yes, the P20 exceeds the wall outlet’s PEAK power as it DOES use a bank of capacitors. This isn’t a forever, but a PEAK, the manual also explains all this. The wall is (20A X 120 V)*.85 = about 2000VA continuous. The P20 can hit 3600VA peak.

As the P20 REGENERATES AC, the AC RF coming in is also rectified out at the AC to rectified DC stage. It ALL goes to DC. PS Audio can elaborate more on that.

The harmonic distortion in the P20 runs very low at 0.5% and is displayed with the on-board oscilloscope and the input to output THD is real time monitored.

The P20 also has an excellent surge current protection built in to keep your stuff safe.

A good power cord can REDUCE the GROUND differential to the P20, and NOISE is the voltage drop across the cord times and noise in the cords GROUND.

A lower DCR is always better in a cord that has a good deal of current going through it. Any time we put a cable between the all outlet and our stuff, we can create a ground loop based on the resistance of that wire. Technically all our grounds should be ZERO difference to the wall from all our stuff. It isn’t. The higher the current draw a device has, the larger AWG cord you need.

I have not experienced a “sound” using the P20 with a 10 AWG BAV power cord verses a 1K reference 10 AWG power cord, and that’s good! The P20 should sound like “nothing” but your equipment, and that’s what I hear.

I have pretty good power as is at 0.3% THD and 120V incoming, but lightening is an issue so the P20 is worth the price for the PROTECTION and the higher PEAK power, both.

Get a quality 10 AWG cord and you should be set. Try a few and see on the “sound”, some say it varies. I can’t comment as my set-up doesn’t so much.

I use my P20 with ONE 20A outlet,but have two T+A M40 monoblocks (550/1100/1800 into 8/4 and 2 ohms). No way I can reach that with ONE P20, I’d need another one and another separate 20A outlet. But, I’m not a head banger and the amps sound great at far lower power levels…maybe 100 watts peak. The P20 is a monster when needed but efficient at idle, too, 35 watts or so if I remember correctly (nothing plugged in and “on”).

Galen Gareis


@rower30 thank you so much for answering.very well articulated indeed.

  • will wait for someone from psaudio to answer on noise and filtering
  • would be interested to know for how many mS the peak can be sustained by the power plant
  • also if we look at the manual ,the peak rating is same for p12,p15 and p20 which is all 3600VA
  • would have expected a higher peak rating for a higher end model.hope at least the peak sustenance in ms may vary if the higher end unit has more power supply capacitance

Dear Goodsource,

I have two P20s, each used to separately power my L and R stereo monoblock amps, plus other peripheral devices. Check out my profile for a photo of my listening room layout, if you’re curious.

I was intrigued by the potential for balanced isolation transformers (“BITs”) to complement my P20s, so I did a bit of research on the subject. Now, I’m a happy owner of several PLiXiR Elite BACs.

This thread may be helpful for answering some of your questions related to the P20’s noise isolation /transmission:


thank you for the pointer. this helps a lot. now its clear to me

You’re welcome! :slight_smile:

Yes, Power Plants have far more peak current ability than the wall does and yes, it is because of the onboard power storage.

Power Plants eliminate noise up to about 1kHz but let pass anything over that frequency, and area where the power supplies in the units they feed are most comfortable with removing. This is one of the reasons Power Plants sound so open and powerful, relative to a power filter that strips life off the music.

Your 450 watt amp would do great into a P20 even with the 15 amp circuit.


Hey Paul, I thought that solid state amplifiers, by design and necessity operate in the audio frequencies using transistors with bandwidth up to around 100kHz, and that AC line noise below that frequency is “filtered” out in the process of AC to DC rectification and reactance in the downstream audio circuitry.

Are you sure that the PowerPlant is only good for filtering AC line noise up to 1kHz?

It’s only 100% up to about 1kHz and from there it certainly cleans but not 100%, and really, you don’t want that kind of cleaning because it’ll rob the music of life. Certainly transistors (and tubes) go very high in frequency but their power supplies do an effective job of eliminating any effects of the small amounts of RF and noises present on the line. The problem with power conditioners is their cure is worse than the problems they try to eliminate.



I agree. The manufacturer SHOULD have control over how the power supply manages AC applied and filters RF. This lets the true “sound” of the device to be more consistent to what the designer wants it to be.

Certainly the regenerators do have some RF supression but not as the predominant process as most RF is well in control when DC is regenerated to AC.

Mess with RF filtering upfront of a device, with the P20, and we have two cooks in the kitchen kind of thing.

Galen Gareis

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Paul, thank you so much for clarifying this point, as the magnitude of RF attenuation on the AC line for the P20 had been a mystery until now.

How about for DC leaks and RF on the Ground plug? Parasitic ground plug noise pollution on the Ground line is a big problem in audio; two components sharing the same duplex (and thus the same Ground) will no doubt pollute each other perfectly as they become physically coupled, but what about on different banks on the P20?

There are two duplexes in each of Zones A, B, and C - are the two duplexes inside these individual Zones separately wired to the copper bus bar, such that there is isolation between them (even they share the same on/off relay)?

And what about the single duplexes in each of “high current” Zones D and E - to what degree are they separately wired physically, and hence isolated from each other?

Might there be a measurement which can quantify the amount of DC and RF which may find its way upstream and across the different ground plugs in the rows of duplexes, even across the thick copper bus bars? Is physical separation (plugging in components’ AC power cords as far as possible from each other in different Zones) the best mitigant?

How permeable is noise across the eight duplexes in the P20, and what is the recommended sequence of plug-in, for maximum inter-component isolation?


The Powerplant is SUPPOSED to homogenize the incoming AC so that the outputted AC is consistent, predictable, and repeatable. Filtering the imperfect AC line input, rectifying it to DC and reconstructing it back to AC, outputting a boring but “perfect” sine wave devoid of any distortion from DC to 1MHz - abundant in quantity through a vast reservoir, and powerful in current exceeding the straight-up AC delivered from the wall, IS the goal, right?

Noise which rides on both the AC line and Ground line may indeed be the spice which embellishes the taste of the dish, but I thought that the ideal was NOT to have these variables, or at least to have as little of it as possible. Far from having two cooks in the kitchen, filtering the raw polluted water until it was crystalline and pure, devoid of anything but H2O is really not a bad thing, I think.

Anyway, I applaud the transparency (no pun intended) by Paul to state what the Powerplant can or cannot do. Much appreciated - two thumbs up!

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I hear the logic but…read Paul’s comment. The CHANGE in the units sound can be influenced by too much RF pre-processing such that the last drop is best managed by the equipment maker.

Until I see substantial RF to be demonstrated moving through the regenerators, I’m good with that, keep it sounding good and retain decent dynamics. We tend to create demons that don’t exist sometimes. Let’s find one for sure that effects Vcc voltages and see what happens when we mitigate it.


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Galen, good points!

Paul, let’s see empirical data on how much ideosyncratic (but potentially delicious) AC line RF noise is passed straight through the P20 to exit unscathed through both the AC duplexes and the Ground connectors :wink:

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You’ll enjoy reading this White Paper from Audioquest’s Garth Powell.

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If you test for RF supression, it will have to be a dB RATIO type value as the incoming RF will be variable to the environment.

Like a SHIELD on a cable. It can be say an 80dB shielding dB factor. And, it’s effectiveness swept across a frequency range. Easy to say harder to do to a repeatable agreed upon method.

Galen Gareis

Don’t forget, the POWER SUPPLY (this includes the power filters and regenerators) is the DC supplied to the AC circuit. It controls the GAIN and the signal linearity of the AC “music” circuit. But, the DC circuit is separate from the AC circuit. They are two separate circuit paths.

The CHANGE in the Vcc collector voltage and such MODULATES the AC gain, and this is how we get non linear amplification…we don’t hear the RF or any non DC “noise” as noise but non linear music amplification.

So what? Well, what we need to measure in my thinking is the DC non-linearity at the Vcc and DC circuit BIAS stage over time for DC fluctuations. Those will alter the circuit gain same as moving a pot up or down. Can we detect that DC abberation that alters the AC gain?

Of course, this is the idea behind clean power. The DC stage is dead nuts on voltage target, and can’t sag under load.

We can measure noise all we want, but the rubber hits the road at the DC bias stage that controls how the transistors amplify a signal. No problems there? Problem probably solved.

Galen Gareis

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Well stated!

Good points. And unlikely anyone has done/will do public measurements/reviews on given you’ve got to separate the power supply from the device and test it separately (imagine taking apart a BHK300 just to test its power supply) – so we depend on audiophile equipment manufacturers and their reputations to have put in the investment/effort to ensure their power supplies and related downstream circuitry are as noiseless and stable as possible under operating conditions.

Is the essential question here theoretical or do folks have issues with audible noise?