Power Conditioning / Surge Protection

Appreciate all the EE arguments.Reminds me of college boring lectures.

Keep it simple...where are you going to plug these things into? Certainly not a power strip.  I have a Furman 15 and it does the job. It protects the equipment and has tons of outlets and even recommends certain components go into certain outlet banks.

If a power cord becomes loose or disconnects, it will shut down that component, it will protect against spikes in the power supplied by utilities. Not sure about direct lightning strikes, but the more likely event of a power outage, it will protect as it will shut off the power to the components more smoothly than if there were no conditioner. I think the system sounded a little better when I started using it, but I wouldn't make that the basis of a decision.

You can get a good deal on a used one, so you won't be talking about a whole lot of investment.

Call me skeptical about the environmental protections products as described.  I read the marketing blurb and the patents for the so called "waveform" correction.  Their marketing blurb w.r.t. other surge protectors requiring a good ground to work and theirs does not is just that, marketing. There is no basis for their claim especially. Their waveform correction technology does nothing to protect surges from line or neutral to ground which are important.  Their technology, distilled, is a capacitor across the AC line. They put a inductor in front of the capacitor (and the MOV and gas discharge tube according to the patent), claiming the inductor smooths the clamping. It may do that. It will definitely decrease the effectiveness of the clamping.

Just on the dedicated audio line.

You're welcome tvad. It made a nice difference in my system.

I think it makes most sense to provide surge protection, waveform correction and power conditioning to everything in your home by having an electrician install an Environmental Potentials EP-2050 in your main circuit box. If you have a dedicated circuit to your audio system, add their EP-2750 ground filter in series with that circuit's safety ground.

We had the EP-2050 in our home in Costa Rica where the AC was terrible; power interruptions all the time. Also heavy lightning during the rainy season. Our neighbors had appliances blowing up all the time. We never had an issue over a five year period.

After reading this paragraph from the Stereophile review of the Richard Gray Power Stations, it's not hard to see why you never see them advertised in the magazine.

Audio Line Source lobbied hard for a review. Here it is....

The Richard Gray's Power Company 400S manifested the same voice or coloration no matter how I used it. It sounded like your windshield looks after a big rig blows by in a rainstorm: The first swash of the blades cleans things up, but the view remains rather obscured. Unfortunately, sweep after sweep, the view remained the same, as through the window of an old, abused New York taxi. Another analogy: Drop your forearm into a sandbox and sweep it broadly across the surface. That's what the 400S sounded like.

The irony of a company whose very reason for being is the pursuit of pure power using a crappy stock power cord in its products is rich.

    I run the RGPC 600 into a Hubbell outlet . Since I run low power tubes my amp is through it too . I then run Morrow level 4 power cords from the conditioner to the units . I’ve had numerous power outages without any damage . However living in central California, I don’t need protection from lightning strikes . All my connections have been cleaned and conditioned with Deoxit . After some time I changed the stock power cord on the Gray to a Shunyata Venom 20 amp rated . I immediately noticed an improvement in my system. If I ran a big SS amp(s) I’d forgo protection and go straight into the outlet , YMMV . 

Almost forgot 2 Paradigm Sub 2's...

What I use is a Sub Box wired with some old stove wire That's as big around as your little finger around 2 gauge. 20 amp breakers @ sub box to feed Duplexes via 10 gauge solid Copper That feeds a Furman IT Reference 20i. I can tell it works great as no more dimming of lights. 8805 Marantz AV-XPR-2--XPR-5 and 4 Emotiva 100's series 2 also a Phase Linear 500 for zone 2. Sounds fantastic and most responses are WOW so I Would say this works well but that's just me --50 year Fanatic since the Sixties..

This is always a dangerous topic on an audiophile forum😄  Recently, I have noticed a trend in both of the rags I read for Reviewer's reference sytems to include the AQ Niagara 5000.  Maybe it is advertising dollars or a better loaner program, but there it is along side all of the other best products.  I recently added one to my new system (Moon Evolution Series stack, mono blocks, 802's and a stereo pair of REL 812's) and there was an immediate, obvious, improvement.  I was surprised that the subs were the first thing I noticed.  More speed, power at the same volume.  I also noticed improvements with the transients and openness of the system.  With all the new power cables (Mostly mid-level AQ stuff) and the $5000.00 unit  it was about $7000.00 invested in power conditioning...a little less than one Moon component😄  Was it worth it?  Well, marginal gains are expensive in this sport, but it easily added as much improvement as one of the Moon pieces!  IMHO

jafant

The two units I have don’t show a name or model number. The RGPC logo is different from that on current models. The folks at RGPC told me it was an early version of the 400. They’ve made some changes since then but I’m told they don’t really wear out. It seems to sound fine in my system

puppyt

I have owned a RGPC Pro 400 since 2004. Never an issue.
Which products do you own?

Happy Listening!

Lots of interesting commentary here. Much appreciated. I actually called RGPC and spoke to Alex.  He couldn’t have been more helpful. Using serial numbers he was able to determine that I have one of the original predecessors to RGPC 400 Pro. He sent me a ton of information on how they work (as both a power conditioner of sorts and a surge protector) and the best way to use them. (Recall in my original post that I bought them years (20 or so) ago after being upsold by a now out of business stereo store.) I never really understood how they worked and what they were really for other than surge protection. Now I know a lot more. For now I am running my digital equipment (CD player, server, streamer) through one RGPC and running my turntable, phono preamp and integrated amp through another. Both are plugged into a dedicated circuit. I also have a whole home surge protector so I feel pretty good about my gear being protected. 
With all that said, I have also preordered the Niagara 1200. When that comes in, I will use it for my source equipment and amplification and use the Richard Gray’s for my subs which are currently plugged into non-dedicated wall outlets. The sub cord cords aren’t long  enough to reach the Richard Gray’s now but that won’t be a problem when I get the Niagara and can dedicated a Richard Gray to each sub. Very excited to see how this all turns out.

For what it’s worth, I use an RGPC to distribute power to all of my source components including my new LG OLED. The RG plus a Shunyata cable made my old Sony 2K pop with great blacks, etc. Unfortunately, almost unbelievably, this new LG comes with a hard wired ac cable. I’m sure it appreciates the RG to plug into. My power units all plug straight into a dedicated line, but I’d sure like to try a Niagara on them some time.

@audio2design, 
Though I am not conversant with electrical design, I can see you are.
Trying to get through to some members is like 'preaching to the choir'.
Bob

Yeah, I still believe his is marketing wording talking here. 

Given how an inductor works, putting it in parallel with the line is counterproductive.   The word "Parallel" here means connected from Line to Neutral or from input to output with the grid wire shunting it.   Either way, it is counterproductive - in the first case, inductors don't work that way, in the second case, it is effectively out of the circuit path.   

They could, and probably do, use a common mode inductor, which would explain using the word balanced, but the two inductors are still in series with the load, not in parallel with it and definitely not in parallel with the grid line.  The RFI capacitors, MOV's, resistors, GDT's, voltage clamping diodes, will all be across the line. that is, connected from line to neutral.

Reviewers often quote manufacturer's literature in their discussion, so the fact that reviewers state the same thing doesn't mean they verified the claim using standard engineering electrical terminology. 

spatialking285 posts11-07-2020 6:07pm"....The "inductor in parallel with the line" term must mean in series with the line, since it is counter productive to put it in across the line, and in parallel means the line is shorting it out.  If they mean something else, then it is not in parallel with the line."

The SoundStageNetwork and Stereophile reviewers (see links above) both state that the inductor is wired in PARALLEL with the AC line. An interesting departure from more modern designs in which series-mode surge suppressors use an inductor wired in series with one leg of the AC line. 

Charging pulse starts at the bottom of the ripple and ends at the peak of the waveform. When ripple is larger this time gets longer. When you comprehend this we can go forward

.
It is impossible for you to discuss this as you don't understand what is happening. It is unfortunately obvious to me you have never had something like this on the bench, never had something like this in a simulator. You are just trying to run it through your head and are doing it wrong. You repeatedly assume the charging current is the same in all circumstances. If the circuit changes, i.e. you add resistance or inductance to the charging circuit, then everything changes. The waveform of the charging current changes, the total conduction angle changes, etc.

Amount of ripple depends on capacitance and load current and does not depend how capacitor is charged since ripple is an effect of voltage drop during capacitor discharge cycle hence has nothing to do with capacitor charging.

You are painfully showing here that you have no idea what is actually happening in the circuit. Sorry can't call it any way but that. Unless you learn this is not the case, you are unable and uneducated enough to discuss this. That is simple reality.  It is not my job to teach you about the basic concept of choke regulation in a power supply, but it is your job to learn it if you want to call other people "low in knowledge" and not have egg on your face.

Amount of this voltage drop (amplitude of ripple) defines width of charging pulse, since capacitor is charged only from the bottom point to next peak. This bottom point was defined by discharge cycle thus charging has nothing to do with it. 

Again, you are showing that you simply don't understand what is happening in enough detail to form any coherent view on what is happening. Amount of voltage drop does not define the width of the charging pulse. The amount of time the input voltage (rectified) is above the output voltage (rectified) defines the time of the charging pulse, literally by definition and by any coherent view of how the circuit operates. We have already determined that the average rectified rail voltage will be lower. Guess what, that means that the amount of time the rectified input waveform will be higher that the output increases.

PFC does not work by by extending conduction angle but rather eliminating (shifting) phase between voltage and current to present resistive load to mains. 

I said the LC circuit in the Furman works by extending conduction angle, I did not say that was what PFC in general was. I can't post pictures here, but perhaps this will help you understand it a bit better as this is exactly what an inductor will do in a linear power supply.  The C in the Furman as pointed out earlier, when combined with most audio amplifiers, will be near useless in impacting PF or THD for that matter.

https://www.allaboutcircuits.com/technical-articles/power-factor-thd-why-linear-power-supplies-fail-...
The fact this article shows the inductor in the output circuit is meaningless. It would work exactly the same in the input circuit, obviously with the inductor value adjusted based on the transformer turns ratio.  The L in the Furman absolutely increases power factor in a linear amplifier. It absolutely is power factor correction for a linear amplifier, however, its effectiveness will be highly dependent on amplifier capacitor bank size and odds are it will rarely result in a high power factor.


Based on what you have written here, by understanding of electronics and especially power supplies and power electronics is obviously way more extensive and accurate compared to yours.


Here, maybe you can increase your knowledge so we can have a proper discussion:

https://sound-au.com/lamps/pfc-passive.html#acc

Oh, and P.S., even if your capacitor bank is larger once you hit a practical size, the peak current and the charging waveform starts to look the same.   I will let you figure out why, but this may give you some hints, see section 5.3.

https://sound-au.com/power-supplies.htm

Charging pulse starts at the bottom of the ripple and ends at the peak of the waveform.  When ripple is larger this time gets longer.  When you comprehend this we can go forward.

Amount of ripple depends on capacitance and load current and does not depend how capacitor is charged since ripple is an effect of voltage drop during capacitor discharge cycle hence has nothing to do with capacitor charging.  The way capacitor is charged will affect voltage on capacitor but ripple will be always the same percentage of this voltage.  When you comprehend this we can go forward.

The ESR of the film capacitor is almost meaningless as it does not charge the capacitors of the amplifier.

ESR is very important since any ESR in the charging circuit will limit maksimum voltage on capacitor.  When you comprehend this we can go forward.

Of course it will get longer. How do you think an LC based PFC works? It works by essentially extending the conduction angle .... i.e. the time the capacitor is being charged.

No it won't.  Voltage droop on capacitor after peak is related only to capacitance and load current.  Amount of this voltage drop (amplitude of ripple) defines width of charging pulse, since capacitor is charged only from the bottom point to next peak.  This bottom point was defined by discharge cycle thus charging has nothing to do with it.  PFC does not work by by extending conduction angle but rather eliminating (shifting) phase between voltage and current to present resistive load to mains.  Averaging (filtering) current pulses coming from PS to draw current from mains during whole cycle is exactly what Furman does.  They call it (improperly) Power Factor correction but it does not change any conduction angle.  It only averages current pulses over whole period.  When you comprehend this we can go forward.

Your understanding of electronics is poor, IMHO and I find you keep arguing just for the sake of it.  Sorry, for the "when you comprehend..."  but that's the unpleasant language you use and another reason I don't want to continue discussing this and perhaps anything else in the future. 

Bigger ripple means longer charging time - ALWAYS!, but you disagree with this.

No it does not and until you understand this you will never be able to move forward. It only means more ripple IF the charge current is the same, and the charge current will be much different with added resistance.

Ripple is a function of capacitance and load current.

No, it is a function of capacitance, load current, and the way the capacitor is supplied with power.

Yes, additional impedance will make charging pulses smaller, because they depend on source voltage divided by impedance in the charging circuit - but charging time will not get longer!

Of course it will get longer. How do you think an LC based PFC works? It works by essentially extending the conduction angle .... i.e. the time the capacitor is being charged.

Yes, Furman’s output capacitor appears to be connected in parallel to electrolytic caps, but is not. It is on the the other side of the rectifier on the AC side. Voltage on this capacitor follows AC voltage cycle but any loss of charge caused by PS charging pulse is replenished from energy stored in the inductor thru the whole cycle. In addition this (huge!) capacitor has very low ESR

Again totally wrong interpretation of what happens. The diode starts conducting when the AC capacitor that is not at all huge in terms of capacitance compared to the amplifier even adjusted for voltage (it will be a film capacitor versus electrolytics in the amp ....way less storage per volume). And no, the capacitor is not "replenished" the whole cycle. Some of it is being discharged, some it is not. It’s voltage follows the AC line with a lag angle determined by its capacitance and the inductors inductance. Once the diodes start conducting, then the lag angle is a factor of the inductor, the AC capacitor and the dominance DC capacitors due to their much higher reflected capacitance. When the diodes are conducting, the "PFC" capacitor is essentially in parallel with the capacitors on the amp (with the exception of the diode drop). The ESR of the film capacitor is almost meaningless as it does not charge the capacitors of the amplifier.


We are not "arguing". No offence, you appear to have some technical acumen, but you view of how this all works is quite wrong.

I'm just tired of arguing, especially most of people don't follow the subject.  I also don't understand some of your statements.  Capacitor is charged only from the bottom of the ripple to next peak.  Bigger ripple means longer charging time - ALWAYS!, but you disagree with this.

Ripple is a function of capacitance and load current.  At constant load current when capacitors get larger (big capacitance) voltage ripple gets smaller hence current charges will be narrower (and usually of higher amplitude because of lower ESR).  Yes, additional impedance will make charging pulses smaller, because they depend on source voltage divided by impedance in the charging circuit - but charging time will not get longer!  It will be charged exactly the same amount of time - from the bottom of the ripple to next peak. Additional impedance in the charging circuit will only result in the voltage drop and the lower voltage on capacitors. It does not affect charging time within each cycle.

Yes, Furman's output capacitor appears to be connected in parallel to electrolytic caps, but is not.  It is on the the other side of the rectifier on the AC side.  Voltage on this capacitor follows AC voltage cycle but any loss of charge caused by PS charging pulse is replenished from energy stored in the inductor thru the whole cycle.  In addition this (huge!) capacitor has very low ESR.  That way during narrow charging pulses current comes from this capacitor and not from the inductor.  Removing this capacitor would have huge effect on the amp.  Just connect big inductor in series with mains and you will see results.  There are power supplies that charge/discharge capacitors during whole cycle because they have big choke in series but then capacitors' voltage is an average and not the peak of the waveform.

Perhaps we're hijacking this thread?

It is not a matter of disagreeing of agreeing. This is objective engineering, not subjective listening.  Everything in what I wrote is easily verified through simulations or building and testing.  I will absolutely agree that added resistance whether real resistance or AC impedance will limit /reduce the maximum rail voltage and hence the peak volume, but I cannot agree as it simply is not true, that the effect and operation is as you described and to the to the level you described as that is simply not the case, no more than the real world performance of the Furman will be as they describe. I am not making that statement because "I believe" it to be true, I am making that statement as I know it to be true both from a fundamental engineering standpoint, and a practical, having done it, implemented it, tested it. measured it standpoint.


There may be something perceived as lack of dynamics with some filters and some amplifiers, but any real world loss of peak power using real music is going to be fairly small, and unless you are driving into clipping, loss of dynamics should not be an issue with any competently design amplifier. Instead of just taking the easy answer, which means the problem is never solved, it is better to find out what is really behind the perceived difference.

We agree to disagree.

I only stated that when charge time gets higher - ripple is higher (capacitor is charged from the bottom of the ripple to the next peak)

Which is wrong. The next peak (voltage) will get smaller, and the total ripple will be lower. The high frequency ripple (which most impacts THD) in most amplifiers and can induct IMD will get much lower. Don’t believe me then feel free to build an amp and test it and/or simulate one.

I only argue that at the moment when net capacitor current is zero (peak of the wave) voltage on capacitor depends on source voltage and source impedance. That’s the peak supply voltage for the output stage. How much it will drop depends on total source impedance including house wiring, power cord, fuse, transformer windings resistance and added impedance of the filter in conditioner.

Here you are totally ignoring the load the is not synchronous to the source. You can’t do that. That is where the error in your logic is. This only applies, to some degree, at much less than 2x line voltage. Dynamics we tend to associate with mid-bass.

If this filter is poor then voltage drop, especially on inductive reactance, can be high. Even if we assume only 10% it will result in 20% loss of max power - equivalent to about 6% of drop in perceived loudness.

You are treating the "inductor" as a resistor effectively, and the load as a constant current load, both in the DC domain with this argument. Again, that is incorrect logic. Even with 0 resistance, any frequency beyond 2x line frequency in the load (and effectively less depending on timing) mostly eliminates any benefit of charging in the short term.

Large linear supplies have a lot of filter capacitance reducing voltage ripple to very small resulting in even narrower and higher charging current pulses and much higher voltage drops on conditioner’s filter impedance.

And again, if you add resistance or inductance, the size of those charging currents gets less, meaning the high frequency harmonics in them gets less (less noise / THD and potentially less IMD), and the length of time of charging gets longer.

I use Furman Elite 20PFi. They call it "Power Factor Correction", but in reality it is huge inductor in series with large capacitor (in parallel to load) that stores energy delivering up to 55A current for spikes (it presents resistive load to mains).

Let’s look at your Furman. Do you really think it delivers 55A peak currents from that capacitor in your system with a linear supply? It does not, not practically at least. The only time it can supply anything into a linear supply is when the voltage on that capacitor is above the transformer reflected voltage on your linear power supply capacitors. The problem is the voltage on the cap in the Furman and the reflected voltage of the capacitors in the linear supply in the amplifier will be exactly the same as it progresses through the charge (AC) cycle. Effectively, the capacitor in the Furman ends up in parallel to the capacitors in the linear supply (reflected through the transformer) once the diodes start conducting and it does not end up transferring any power at the start of the charge cycle, and only a small amount at the end of the charge cycle when the AC voltage decays. It is likely a film capacitor and hence able to store much less energy than the caps in the amplifier power supply. The only time it will supply a large peak current (very short duration and not much energy), is if the amplifier has a large load right after peak of the AC cycle.


For an LC PFC to be effective as PFC, it must be exactly tuned to the load including the reactive components in the load (i.e. capacitors). Odds are your Furman is rarely presenting something that looks like a resistor to the mains. The inductor does improve power factor and reduce THD on the AC lines, but effectively the capacitor is doing very little to help that due to the nature of the load.


I will guarantee you that under peak loading, due to the inductor in the Furman, the rail voltage on your supply is slightly dropping, and that is a good thing, means the ripple/noise is being kept under control. I would expect taking out the AC capacitor in the Furman would have almost 0 impact on the DC rail voltage in the amplifier under loading but I would not suggest it. What it will be good at is suppressing high frequency noise coming in from the AC line.

I chose the following option: power amplifiers - Isotek Super Titan, then added SR PowerCell Two. (An early choice was - Isotek Titan.)
Sources-PS Audio P10 - > SR PowerCell SX (primarily-PS Audio).
PS. Regenerators always killed my power amplifiers (Classe).
I've heard a lot of good things about Niagara from audiophiles, but I haven't tested it in my system.
I strongly recommend testing High Fidelity Cables MC and Bybee iQSE. I didn't return it.

Audio2design  I did not say that ripple current gets higher.  You argued that voltage on capacitor doesn't drop because charge time is higher.  I only stated that when charge time gets higher - ripple is higher (capacitor is charged from the bottom of the ripple to the next peak)

I only argue that at the moment when net capacitor current is zero (peak of the wave) voltage on capacitor depends on source voltage and source impedance.  That's the peak supply voltage for the output stage.  How much it will drop depends on total source impedance including house wiring, power cord, fuse, transformer windings resistance and added impedance of the filter in conditioner.   If this filter is poor then voltage drop, especially on inductive reactance, can be high.  Even if we assume only 10% it will result in 20% loss of max power - equivalent to about 6% of drop in perceived loudness.  I agree that in this case when amp is within 80% it should not be audible, but people claim it is.  Perhaps voltage drops even more.  Large linear supplies have a lot of filter capacitance reducing voltage ripple to very small resulting in even narrower and higher charging current pulses and much higher voltage drops on conditioner's filter impedance.  Many people report big loss of dynamics with some conditioners.

https://www.changlightspeed.com

Best solution I have found for surge protection, and conditioning (power line noise reduction).

Better than AC regenerators or conditioners with coils.

No residual artifacts at all.

Power factor Correction included.    I use the CLS 709 $1300.

You are saying the voltage ripple gets larger. Prove it. That is a common misconception that is actually not true. The worst case voltage ripple will not get worse with added resistance.

Yes the voltage (average) on the capacitor may be lower. I never discounted that. A lower voltage (which wouldn't be any different from a lower mains voltage) will limit peak output power, but we are talking fractions of a db where clipping will kick in.

Do the actual work. Consider the transfer function. Consider the transfer function in the frequency domain. Voltage ripple will not increase with added input resistance.

Unless the amp is voltage clipping you have not made a good argument for true loss of dynamics though the loss would not be much different than line voltage variation. That resistance limits the peak current but extends the charge time so I your 10A example the peak may drop to say 5A but charge time increases and the voltage drop becomes small overall.

This argument is nonsense.  Charge time increases because voltage ripple gets higher, but capacitor get charged to the lower voltage because of the voltage drop on additional impedance in series.  At the peak of the wave max voltage on capacitor is equal to source voltage (peak secondary voltage after rectifier) minus load current multiplied by the source impedance.  Adding any impedance in series lowers voltage on capacitor at the same output load.

Puppyt, get a Shunyata unit for your low level stuff and have your electrician install a whole house surge protector. Keep a spare handy as they are sacrificial like a fuse. It is best to keep amps away from the other equipment (preferably behind the speakers) and plug them into their own outlets. I do not use anything on them other than shielded power cables that I make myself. 

I have had excellent results with Shunyata Triton/Typhon. I was fortunate to get them for $4500 with 4 Shunyata power chords.
Their retail price when up to $18k! The change was stunning. The change in noise floor is so dramatic that the entire presentation radically changed. But Shunyata makes more affordable units.
A major part of their company makes units for medical and science.
Electron microscopes, etc. They hold many, many patents.

The AC line only supplies voltage for a small part of the waveform every 1/100 or 1/120th of a second. If you are current starving the AC input the you are clipping. The relatively small loss of voltage on the secondary of the power supply due to some level of inductance on the AC would be fractions of a dB in top end.

Far more likely is inadequate components in the AC filter likely selected for continuous current rating but not the peak currents resulting in saturation of the inductor and increasing the THD not decreasing it like it should.

A universal statement about loss of dynamics without a critical look at the real mechanisms results in universal and likely often wrong statements applied to all equipment performing the same function.

audio2design101 posts11-08-2020 11:30am"Garth Powell writes some words but offers no proof or even solid technical discussion. This is word smithing for consumer marketing. The higher current the peaks the larger the instantaneous voltage change which is much harder to filter out for subsequent electronics. That so called compression only happens if you are driving the amp into clipping. If you are not driving into clipping no solid technical explanation has been presented for loss of dynamics. More likely seems a decrease in the THD unless clipping."

The current "compression" that Garth Powell refers to is what I would call current "starving" which can occur in power amps at levels lower than clipping due to transient voltage drops associated with high source impedance. The effect on sound has been experienced by many audiophiles, which is why many plug their power amp (or integrated amp) DIRECTLY into the wall outlet.  

Garth Powell writes some words but offers no proof or even solid technical discussion. This is word smithing for consumer marketing. The higher current the peaks the larger the instantaneous voltage change which is much harder to filter out for subsequent electronics. That so called compression only happens if you are driving the amp into clipping.  If you are not driving into clipping no solid technical explanation has been presented for loss of dynamics. More likely seems a decrease in the THD unless clipping.

Furman Elite 15PF i 

+1   mike_in_nc .... my friend bought Power Plant P600 Power Regenerator and  was very disappointed how it affects the SQ of his system. First I thought maybe it warming up issue or he just too used to previous setup, but when I visited him after couple of weeks and tried different setups it’s was obvious for me too that this power unit has negative effect.  

@audio2design - Garth Powell (Audioquest) talks about current compression in power amps and its effect on sound in his "Power Demystified" article (link above), an excerpt of which is presented below....

There is an additional problem: In order to cover enough range, a passive filter will require some inductance (the “L” in LCR), which will raise the AC impedance somewhat and create a phase lag for power current transients. This is of no consequence to video, computer, or source audio components, as they utilize low-amperage constantcurrent circuits. However, this can severely current compress a power amplifier as its power supply draws down to supply an audio transient, while the power amplifier itself requires a large influx of current to its power supply to maintain low-distortion operation. To get around this issue, many passive AC power filter/conditioners will isolate the circuits that utilize any series inductance for source components only. The circuit without series inductance is set aside for the “High Current” power amplifier outlets. If a power amplifier experiences current compression, the sound that results from an audio system can be described as thin, anemic, muddy, and slow, while the soundstage tends to collapse or pull with frequency during dense or modulated passages.

I am talking about noise and distortion because that is what we hear. The lower the resistance the bigger those spikes are, the bigger the harmonics of the AC and the bigger potential for THD due to AC harmonics.

We don’t hear power loss.

Those spikes are also only at 100/120 Hz so no "benefit" to frequencies above that.

Unless the amp is voltage clipping you have not made a good argument for true loss of dynamics though the loss would not be much different than line voltage variation. That resistance limits the peak current but extends the charge time so I your 10A example the peak may drop to say 5A but charge time increases and the voltage drop becomes small overall.

For those with a technical "thirst", the following are a worthwhile read....

https://www.audioquest.com/resource/1138/Power-Demystified-whitepaper-8-23-18.pdf

https://shunyata.com/technology-guide/

Regardless of what you do have a whole house surge protector installed! Please. There are so many reasons to do so, too many to re-list here.
I use an Audioquest Niagara and can’t hear any difference verses when the Amp is plugged into the wall.
As for the wall; do you have beefed up hospital grade plugs or better? I can’t recommend that enough. Seriously.

Wow, very much appreciate all of the comments even those I don’t understand! I was reading about the AudioQuest Niagara 1200. Anyone have experience with this device?

Why do you keep talking about noise and voltage spikes?
The problem is in narrow current spikes (pulses) charging capacitors that increase power losses on any impedance in series.

During orchestra forte voltage on power supply caps drops.  It is because of capacitor ESR, but also because of voltage drops on on transformer windings (copper losses) and any other impedance in series including power cord, house wiring, conditioner coil etc.  Simply, power supply is not load regulated (voltage vary with load).  Some unregulated supplies are better than the others often because they have oversized transformers.    Increasing capacitance should also help, but creates another problem - lower voltage ripple that results in much narrower and much higher charging current pulses, that will create even more power losses (including core losses for hysteresis and eddy currents because of high frequency content).

So you think large spikes every 120th or 100th of second causing large voltage spikes with high harmonic content is going to create less noise and distortion than a slowly changing voltage at the same frequency? What is the music peak is at 180 Hz or above?

ZeroSurge for protection fitted with an upscale power cord and outlet. Feeding a PS Audio Power Plant through an upscale power cord.

Jeeeez    I tried Richard Gray and they were awful in my system. 

Capacitors charge in narrow current spikes, but they cannot charge to the same full voltage when there is voltage drop on impedance in series.

Perhaps spikes would be 1/12 less since we drop 10V of 120V.   It doesn't change anything.

I did not say more noise.  I believe that amplifier with less regulation will be less linear with changing power supply voltage.  Less linear = more distortions (like loss of dynamics).