Studies On Residential Power Line Noise - Part 5: PS Audio Power Port Premier

[DarqueKnight]

Introduction

I can understand the skepticism surrounding power infrastructure tweaks (power cords, audiophile outlets, power conditioners, etc.). I still struggle with forking over the cash for these types of tweaks even though I clearly hear the improvements they bring. Even more than that, I have been able to measure the performance of power infrastructure gear and gain some quantitative insight into the improvements I hear. Even though I have a fairly good theoretical grasp of what's going on, part of my mind intuitively wants to use the AC receptacles that came with my house and the power cords that came with my audio equipment and the dirty, filthy, yet very expensive, power that I get from the utility company. It can mess with your head a little bit when you try to grasp the concept that changing something in the wall...something far outside the direct signal path...would have even a subtle effect on sound quality. Furthermore, it just seems so unfair to cough up thousands of dollars for a nice audio system and then find out that you also need to cough up yet more $$$ to keep the utility company's power line gremlins at bay so that you can hear all (or as practically and financially close to all) of the resolution, detail, sound staging, imaging, and bass slam that you paid for. I'm not complaining. I knew going into this hobby that the audio rose garden doesn't come cheap.

My interest in a higher quality AC receptacle was piqued after the good results I achieved with the original Power Port (hereafter P2). A number of former P2 users have reported good results with the Oyaide R1 ($130, $145 cryoed). Like many P2 users, I was glad that PS Audio had finally provided a higher performance alternative. I did have some concern about the gold plating used on the copper base metal of the P3. Evidently, PS Audio had some concerns also. This quote is from the original Power Port overview page on the PS Audio website:

"We first considered simply gold plating the contacts of the brass, but quickly rejected that notion when several facts became apparent: gold is soft and will be quickly scraped off of the high spots of the contact area unless a gold plated male plug is inserted, and unless the surface is highly polished beforehand the problem of low surface contact area will not be addressed."

I noted that the Power Port Premier uses extensive gold plating. I assumed that PSA realized gold wasn't so bad after all, since Oyaide and Furutech seem to be using it on their higher end AC receptacles to good advantage. Live and learn. Hence, this question to PS Audio concerning the Power Port Premier's gold plating:

"I have some concern about the durability of the gold plating on the internal blade connectors. Considering the tight grip of the Power Ports on cable blades and the softness of gold, what is the maximum number of insertions/removals before the gold plating begins to deteriorate?"

Their answer:

"I have no idea, but you are right to be concerned about this, of course, as with any quality connection it is important to be sure that things are clean and free of grit to avoid undue scratching and wear, and to try and do the least amount of plugging in and unplugging. If you are planning to use a given outlet for components that will get plugged in and un-plugged many times, the standard Power Port with nickel plating will be a better choice."

Some companies would have asked me to send my power cables to them to have the connectors gold plated, for a modest fee, of course.:) I do not do a lot of plugging/unplugging at my audio and video equipment receptacles. Plus, I am sure the smooth, highly polished nickel contacts of my Premier SC power cables will go easy on the gold plated beryllium contacts of my P3 receptacles. I also dug out my 20+ year old Yamaha C-85 preamp which has gold plated RCA jacks. They are still smooth and bright and shiny, despite my not always using cables with gold plated RCA plugs.


Figure 1. Mmmmmmm...gold...even on the carton. This is no mere box. The P3 is
packaged in an elegant white carton with gold embossing. Nice packaging is an
important part of the audiophile experience.;)


Figure 2. The P3 features a semi-crystalline polymer body and lots of bright shiny
gold plating over smooth creamy rich sounding copper. The "poor cousin" P2 is just nickel plated brass in an ordinary plastic body, but it sounds worlds better than a regular residential grade outlet.


Figure 3. The two-tone effect makes it easy to identify which
outlets are capable of providing Such Good Sound.

I was impressed by the tight grip of the P2. The P3 takes things up a notch to where it takes some effort to insert and remove power cable connectors. What I do is grip the connector housing with four fingers and use the thumb of that hand to push the cable out of the receptacle. If this one-hand method is not efficient for you, I would recommend bracing the wall plate with one hand and slowly removing the cable with the other. Over time, I expect that simply grabbing the cable connector and yanking it out of the receptacle, without bracing, will weaken the retaining screw threads to the point where they will fail.

Economic Incentives

Even in the best of times, luxury items like $99 AC receptacles can be a tough sell. When times are hard, some $ incentive usually proves beneficial to manufacturer and customer. The price of the Power Port Premier is $99 for one or you can buy a 5-Pack for $399, which drops the price per receptacle from $99 to $79.80 (20% off). I just happened to need five P3's: three for the two channel system and two for the home theater.

In order to keep current P2 owners from migrating over to the likes of Oyaide and Furutech, from now until the end of December 2008, PS Audio is offering a trade in promotion allowance of $25 for a P2 that is traded in for a P3. This dropped the effective price to $54.80, which I could comfortably afford.:) It also saved me the trouble of having to sell my old P2's. Twenty five bucks is about what they sell for on the used market (new MSRP $50, average street price $35).

I was planning to order a pair of Oyaide R1's for evaluation but Paul McGowan took a cue from Marlon Brando and made an offer I couldn't refuse. Let's see...$54.80 for the P3 copper/gold/beryllium/PBT receptacle or $145 for the R1 copper/gold/beryllium/PBT receptacle?


Figure 4. The home theater system received its fair share of P3's.

The Sound: First Day Impressions

Some P2 users complained of initial harsh, bright, brittle sound. Some users said the harshness diminished over time but never went away, even after the recommended 300 hour break in. I never experienced such unpleasant sound with the P2. Sometimes, for a variety of reasons, a particular accessory just doesn't play well with what you have. It is not necessarily a bad reflection on either the accessory or the system it was used in. The results from these kinds of tweaks are highly system dependent.

My Parasound Halo JC 1 monoblock amplifiers are each fed by a dedicated 20 amp circuit. The source components are on another dedicated 20 amp circuit and are fed regenerated AC from a PS Audio Power Plant Premier. Prior to this evaluation, the amplifier AC circuits and the third dedicated circuit for the source components were terminated by P2 receptacles.

The right channel P2 was replaced with a P3 and monophonic program material was compared between the left and right channels. The right side was apparently a little louder, indicating a lower noise floor, and the bass was more tactile and defined. Bass instruments had a heavier and more articulate "growl" component. The midrange and treble was also a little clearer.

The P2's of the two other AC circuits were replaced and evaluation was done in stereo mode. In addition to the improvements noted above, now the midrange and treble was noticeably heavier and there was an enhanced sense of depth between images in the sound stage. The sound stage width and height did not change, but images at the far sides of the stage were apparently louder.

PS Audio recommends a break in period of 300 hours. I'll follow up after that milestone has been passed. This was an auspicious beginning, therefore I expect more good sound after break in.

[DarqueKnight]

Noise Analysis

I took noise spectrum measurements of the right amplifier's AC circuit terminated with a regular contractor grade receptacle, a Power Port receptacle, and a Power Port Premier receptacle. The Fast Fourier Transform plots showing the power spectrum in each case are given in figures 5-7. If you save figures 5-7 and then click through them in succession, you will see that the fundamental and harmonic structure of the power basically remains the same, but the "dirt" down around the noise floor gets lower in magnitude and density.


Figure 5. Good: Dedicated audio circuit with regular household AC
receptacle.


Figure 6. Better: Dedicated audio circuit with P2 AC receptacle.


Figure 7. More better: Dedicated audio circuit with P3 AC receptacle.

Figures 8 and 9 show the result of a 61 Hz test signal measured at the SDA inputs of the left and right speakers. The amplitude and density of the noise on the right side, with AC power fed through a P3 receptacle, is significantly lower than that of the left with the P2 receptacle.


Figure 8. Dedicated audio circuit with P2 AC receptacle. FFT of 61
Hz test tone taken at left speaker SDA input.


Figure 9. Dedicated audio circuit with P3 AC receptacle. FFT of 61
Hz test tone taken at right speaker SDA input.

Of course, simple noise spectrum measurements cannot completely quantify the sonic improvements brought by the P3. Since the power signal is interacting with the P3 at the molecular and atomic level, we would need to take measurements at that level to fully understand what is going on.

Conclusion

PS Audio brought the first audio grade AC receptacle to market in 2002. The original Power Port was manufactured for PS Audio by Hubbell and was a customized version of a Hubbell hospital grade receptacle. Prior to that, audiophiles were replacing standard residential receptacles with hospital grade outlets. Once it became evident that there was $$$$ to be made in this accessory niche, Oyaide, Furutech and others joined the party. The highly regarded Oyaide R1, which was introduced in 2007, has come to be regarded by some as the finest AC receptacle available. It costs $130 for the regular version and $145 for the cryogenically treated version. An aftermarket cryogenically treated version of the Power Port Premier is available from Cryo Parts (www.cryo-parts.com) for $110. Cryo Parts also offers a cryoed version of the original Power Port at no extra cost over the $50 retail price. A PS Audio representative said that they have not had a chance to listen to any of the cryo treated Power Port Premiers, but that they do trust Cryo Parts expertise.

The Power Port Premier bears some similarities to the Oyaide R1. Both use PBT (Polybutylene Terephthalate) for the body material, although PS Audio uses a proprietary PBT composition. Both use beryllium copper contacts and extensive gold plated copper parts. One wonders why PS Audio was so late coming to market with an improved AC receptacle, even though the faithful were clamoring for one for years. Perhaps they didn't think sufficient market demand was there. Perhaps they were busy with other things. Their engineering staff has been coming out with a lot of nice new stuff since 2002.

I'm sure the similarities between the Power Port Premier and the Oyaide R1 are too enticing for the professional audio reviewers to ignore for long. A shootout is likely forthcoming...if it hasn't already been done and is simply awaiting publication. Since PS Audio's marketing literature for the P3 says that "The Power Port Premier is the ultimate AC receptacle on the market today", I'm sure they have compared the P3 to the top contenders out there and have the performance fire to go with the marketing smoke.;) The P3's physical and sonic superiority over the P2 was immediately obvious to me. There weren't any diminishing returns either. The P3 costs twice as much as the P2, but it is easily 2X (or more) better when all the improvements in detail, articulation, clarity, imaging, sound staging, noise reduction, and gripping power are considered.

If the P3's perform the same or better than the R1's, cost 1/3 less, and come in much more distinguished looking packaging, then PS Audio has an excellent chance of climbing back to the top of the audiophile AC receptacle market.

Addendum

I was pleasantly surprised to see that my power quality had significantly improved, although it is still not back to pre-hurricane Gustav quality. A month ago, and as little as two weeks ago, my AC power had much higher levels of 5th and 7th harmonic distortion and other noise. This contributed to noticeably flattened power waveform peaks. The 5th harmonic was, and still is, higher in amplitude than the 3rd harmonic. After Gustav, the 7th harmonic was close in amplitude to the 3rd and 5th, but lower than either of them. Ideal is for the odd order harmonics to diminish in amplitude as as you go up in frequency. Even order harmonics are usually not a concern in North American public utility systems. Voltage levels have stabilized to pre-Gustav variances. After Gustav, the voltage level would also vary -1/+4 within a single hour rather than the pre-Gustav variation of -1/+4 within a 24 hour period.


Figure 10. AC power waveform with ordinary residential grade outlet
measured on 10-28-08.


Figure 11. AC power waveform with ordinary residential grade outlet
measured on 11-14-08.


Figure 12. AC power waveform with ordinary residential grade outlet
measured on 11-28-08.


Associated Equipment

Pass Laboratories X0.2 Preamplifier
Pass Laboratories Xono Phono Preamplifier
Parasound Halo JC 1 Monoblock Amplifiers
Teres Audio Model 255 Turntable
Ortofon MC Windfeld Cartridge
Graham Phantom B-44 Tonearm
Cary Audio CD 306 SACD Player
Polk Audio SDA SRS 1.2TL Speakers
Audioquest LeoPard Tonearm Cable
Audioquest Sky XLR Interconnects
Audioquest Everest Speaker Cables
PS Audio Power Plant Premier Power Regenerator For Source Components

References

PS Audio Power Port Review

Studies On Residential Power Line Noise - Part 1

Studies On Residential Power Line Noise - Part 2

Studies On Residential Power Line Noise - Part 3 - PS Audio Power Plant Premier

Studies On Residential Power Line Noise - Part 4- PS Audio Premier SC Power Cord

[DarqueKnight]

The Power Port Premier sounded good immediately after installation and gradually improved up to the 150 hour mark. After that, I did not hear any changes. The manufacturer recommended break in time is 300 hours.

The most noticeable changes were in continual small improvements in bass detail and impact.

The P3's had current running through them continually since I leave my power amps on 24/7 and they draw 2 amps of idle current.

[mmadden28]

Goes without saying, but Nice write-up yet again. Thanks for the info and research.

[DarqueKnight]

Lee Weiland of Cryo Parts contacted me after reading my initial post and asked if I would like to evaluate a Cryoed P3 against the regular P3. Up to this point, my only experience with cryogenically treated items were the cryogenically treated wind instruments that some of my musician friends prefer. I have never had any interest in cryo treating my saxophones because the differences I heard in cryoed musical instruments could be achieved by tuning, different mouth pieces, etc.

The proponents of cryogenically treated wind instruments say it was money well spent. It is not expensive unless it is done to an instrument, like a saxophone, that has to be totally disassembled. Cryo destroys neck corks and tone hole pads. All metal instruments like trumpets are the best candidates for low cost cryo treatment.

Cryogenic treatment is more than just "freezing". The interested reader can find much excellent reference material on the procedure.


Figure 1. A Power Port Premier fresh from the freezer.

Some Measurements

The cryoed P3 (hereafter C-P3) consistently measured a little better than the stock P3 with lower noise density and noise amplitude.


Figure 2. FFT of power from stock P3.


Figure 3. FFT of power from cryoed P3.

Figures 2 and 3 show the FFT of the power from the stock and cryoed P3's. The trash around the noise floor was lower in amplitude and density with the C-P3, but DC component and the 3rd, 5th, and 7th harmonics were consistently 1 dB higher than with the P3.

Figures 4-7 show the differences in the FFT's of 1 kHz and 61 Hz test signals taken at the left and right speaker's SDA inputs. It is easier to see the differences if you save the pictures and flip back and forth.


Figure 4. FFT of 61 Hz test signal taken at left speaker's SDA inputs.
Left side power amp is fed through stock P3.


Figure 5. FFT of 61 Hz test signal taken at right speaker's SDA inputs.
Right side power amp is fed through cryoed P3.


Figure 6. FFT of 1 kHz test signal taken at left speaker's SDA inputs.
Left side power amp is fed through stock P3.


Figure 7. FFT of 1 kHz test signal taken at right speaker's SDA inputs.
Right side power amp is fed through cryo'd P3.

The Sound

I usually listen first and measure second. The noise measurements came as quite a surprise because the sound of the C-P3 was unbearable. Cryo Parts specifies a break in time of 400 to 450 hours for the C-P3 compared to PS Audio's recommended break in time of 300 hours for the stock P3. My stock P3's had 264 hours of continuously running current through them at the time of these measurements. The JC 1's pull 2 amps of current continuously.

When playing monophonic material, the sound on the right was veiled, apparently lower in volume and the bass was broken. Bass detail and articulation was thrown out of the window. The bass coming from the right speaker sounded like it was produced from one of those loudness contour circuits on a cheap preamp...boomy.

I was going to let the C-P3 stay in my system as it broke in so that I could hear the changes...but it was too rough sounding. It needed to go to charm school before being reinserted into my two channel system.

Charm School Is In Session


Figure 8. A growing trend in audiophilia is to let your refrigerator
help with break in duty.

I replaced my refrigerator receptacle with the C-P3. I'll let it "soak" there for 450 hours and then re-evaluate it in my two channel system. Of course, the refrigerator motor does not run continuously, but it sucks a hefty amount of current from the wall when it does.

More later.


The monoliths are getting increasingly annoyed
by their owner's incessant fiendish experiments.

Really? Oh, I forgot to tell you guys...I'm getting a new
oscilloscope this month with more whiz bang meter pontiff
fetish features.~DK

[rlmacklin]

Now if only PS Audio would make a version of Power Port Premier that will fit as a replacement for the specific Power Ports on the Power Plant Premier...

[DarqueKnight]

PPP owners have been screaming for such an upgrade. PSA is not agreeable because:

1. It would require a significant redesign of the PPP with a commensurate significant increase in price.

2. They are not so sure the sonic benefits of adding P3 outlets to the PPP would be worth the costs of research, retooling, and increased cost to the customer.

3. Their (small) engineering department is overloaded with other more pressing tasks and they just can't have a look at it any time soon.

[Face]

3. Their (small) engineering department is overloaded with other more pressing tasks and they just can't have a look at it any time soon.

Ask them to outsource it to you. :D

[RandyWilliamson]

Awesome write up!! would you say the noise is audible like as a form of hiss when no signal is applied sometimes? I mean it is low at even medium volumes but when high you can definitely hear noise clearly.

[DarqueKnight]

Awesome write up!! would you say the noise is audible like as a form of hiss when no signal is applied sometimes? I mean it is low at even medium volumes but when high you can definitely hear noise clearly.

No, it is not that type of noise. It is more like salt dissolved in water. You can't see the salt, but you can taste its effects.

[DarqueKnight]

Ask them to outsource it to you. :D

You know I hate doing mod work. I wish I could outsource my projects.;)

[DarqueKnight]

The caption for Figure 7 in post # 5 should read:

"FFT of 1 kHz test signal taken at right speaker's SDA inputs. Right side power amp is fed through cryo'd P3."

I have asked a mod to make the correction.

[RandyWilliamson]

[QOUTE]
The monoliths are getting increasingly annoyed
by their owner's incessant fiendish experiments.

Really? Oh, I forgot to tell you guys...I'm getting a new
oscilloscope this month with more whiz bang meter pontiff
fetish features.~DK[/QUOTE]

Hilarious.

[DarqueKnight]

The cryogenically treated Power Port Premier (C-P3) did not favorably impress when it was first installed on December 9th. The vendor specifies a 450 hour break in. The C-P3 was installed in place of my refrigerator receptacle and left for 21 days (504 hours). Prior to any critical listening, the vendor further specified another 50-100 hours after re-installation to allow the C-P3 to "stabilize". I let the C-P3 soak in my two channel system for 50 hours while the JC 1 pulled two amps through it continuously while idling and even more amps while playing music.

Immediately after re-installation in the right side of my two channel system, I noticed that the C-P3 sounded world's better. The only difference between it and the stock P3 on the left was in the bass region. Listening to tracks from "Saxophone Colossus" (a monophonic recording) and going from side to side with the balance control, the bass was less defined and was apparently louder on the right. Bass notes that were clearly articulated on the left were mumbled and slightly slurred together on the right.

After 50 more hours, the bass anomalies were still there to the same extent. The C-P3 still measured better than the stock P3 and measurements were similar to those previously shown. By this time, the stock P3 had 840 hours of running continuous current through it. I can't say for sure how many hours of continuous current was run through the C-P3 because my refrigerator does not continuously draw heavy current. The C-P3 did have 576 hours of installed time.

I did not want to go through another "soak" cycle, which probably would have removed the last vestiges of bass abnormalities and, I assume, surpassed the stock P3's performance. After all, the C-P3 was coarse and unlistenable prior to the first soak cycle and improved dramatically afterward. The C-P3 was returned to the vendor. From my readings, I surmise that this and other cryogenically treated receptacles require long break in times, but that the long wait is worth it. Anyone wishing to audition this or any other cryogenically treated receptacle will have to be very patient or employ some type of "cooking" device to break it in. I tend to gravitate toward gear with relatively short break in times or that sounds good right out of the box and then gets better with age.

[mmadden28]

One (I) would think that for a customer to get true satisfaction from a product and to avoid any negative reviews from those that would judge the product without any excessively long break-in, that companies with products like this would break/burn the product in for the customer before it's shipped. I'm not talking about recieve the order than start the burn-in, I'm talking about having pre burned stock on hand. Well my opinion anyway.

[DarqueKnight]

That is what I would prefer. Particularly if the manufacturer or vendor knows that the sound is much less than optimal until broken in.

Sometimes a manufacturer or vendor does not have the time and other resources required to do a pre-break in.

[comfortablycurt]

That's a great write up DarqueKnight...it answered a lot of questions that I'd actually been pondering lately. I've been wondering if it really was worth it to go with a dedicated audiophile outlet...you've just convinced me.

Lemme tack another thing onto the old wishlist now... this list is getting pretty big...:D

[SEH]

One (I) would think that for a customer to get true satisfaction from a product and to avoid any negative reviews from those that would judge the product without any excessively long break-in, that companies with products like this would break/burn the product in for the customer before it's shipped. I'm not talking about recieve the order than start the burn-in, I'm talking about having pre burned stock on hand.

It's possible that this isn't practical because components revert to their pre-break-in parameters after a rest period, as during shipping or while sitting around in stock before sale. It's also possible that a very significant change during break-in is actually the adaptation of the listener to the component. Even with loudspeakers which can change their parameters in measurable ways when first exercised, after a day or so it could be the ears that are really breaking in. If any of that is the case (and I suspect at least some of it is, or "Our stuff is broken in when you buy it" would be employed by the marketing departments), then a pre-broken-in part would still need break-in by the owner when put into service.

[DarqueKnight]

It occurred to me that some might think that since the upper and lower outlets of a receptacle are ganged together, there would be no need to break in both outlets. That is wrong. Both outlets must be broken in. The upper outlets of the stock and cryoed receptacles did not have current running through them during break in. There were audible and measurable differences between the upper and lower outlets of each receptacle.

Figures 1 and 2 show the Fast Fourier Transform plots of the signal and noise spectrums for the upper and lower outlets of the cryoed Power Port Premier receptacle.


Figure 1. FFT plot of non-broken in top outlet of cryoed P3.


Figure 2. FFT plot of partially broken in bottom outlet of cryoed P3.

The cryoed receptacle's bottom outlet, which had current running through it for several weeks, displays lower noise amplitude and density.

Figures 3 and 4 show the Fast Fourier Transform plots of the signal and noise spectrums for the upper and lower outlets of the stock Power Port Premier receptacle.


Figure 3. FFT plot of non-broken in top outlet of stock P3.


Figure 4. FFT plot of broken in bottom outlet of stock P3.

The stock receptacle's bottom outlet, which had current running through it for over a month, displays lower noise amplitude and density than the upper outlet.

Although the cryoed receptacle's outlets displayed lower noise amplitude and density than the corresponding stock receptacle's outlets, the sound of the stock receptacle's outlets was better.

I used track 5 ("Blue 7") of Sonny Rollins "Saxophone Colossus" SACD to evaluate the upper and lower outlets of each receptacle. The first minute of this track consists of just a bass line and the drummer playing the cymbals of the drum kit. There is also audible tape hiss, which is typical of recordings from the 1950's.

Comparing the left side stock receptacle broken in lower outlet to the right side cryoed receptacle non-broken in upper outlet, the right side displayed the following sonic attributes:

1. The sound was veiled overall, but still much better than when new.
2. Bass was muddy.
3. The tape hiss was inaudible.
4. The drum kit cymbals lost much of their metallic shimmer and airiness.
5. The overall apparent sound level was lower.

Comparing the left side stock receptacle broken in lower outlet to the right side cryoed receptacle partially broken in lower outlet, the right side displayed the following sonic attributes:

1. The veiling was restricted to the bass region.
2. Bass was not muddy, but was less defined than the left side.
3. The tape hiss was still audible but slightly muted.
4. The overall apparent sound level of the bass was louder.

Comparing the left side stock receptacle broken in lower outlet to the right side stock receptacle non-broken in upper outlet, the right side displayed the following sonic attributes:

1. Tape hiss was slightly muted.
2. Overall less definition and clarity, particularly in the bass.
3. Overall sound level was a little lower.

Comparing the left side stock receptacle broken in lower outlet to the right side stock receptacle broken in lower outlet:


No audible differences.

[Lasareath]

Thanks again DarqueKnight for another wonderful review. I will be buying a 5-Pack of the Power Port Premier outlets when I wire up my new Audio Room.

I just have a couple questions:

Metal outlet boxes or Plastic?

BX or Romex?

Since I will be adding a sub-panel for my new audio room and all new circuits I want to do it correctly. Does PS Audio have recommendations on what type of Panels, Wire & outlet boxes to use?

Thanks,

Lasareath

[analog97]

One question here about electrical phase. The 2 hot legs of a standard electric panel are each 120 Volts, but they are out of phase by 180 degrees. That is why (as I understand it) you can get 240 Volts between them. So, if I or anyone else wants to run 2, 20 amp circuits for his system and you put both circuit breakers on the same side of the electric panel, I think the result is that each will be out of phase by 180 degrees. I really don't know what difference this would make, but my question is whether it is better to run each circuit from the SAME panel hot leg, rather than one from each side? Any electricians or EE's out there? Maybe I missed something?

I think if you put in a "twin" breaker in the panel, each hot leg comes off different sides and the result is each circuit is 180 out of phase. That is why it seems to me it would be preferable to use two single breakers, one on each side of the panel. Maybe I missed something in DarqueKnight's posts about this.

[inspiredsports]

This is a great article as I am at that point in my tweaking where I have just added a separate circuit for audio to my 300A main breaker box. It's also nice that it's very short run as the main happens to be in my "man cave" in our finished basement.

A couple of these tricked out reseptacles would be nice and are relatively affordable, but that brings up even more questions. Are there special breakers that would improve the signal right at the main bus? Are there better grades of romex that could be used in the run from the main to the dedicated reseptacles?

Side Note: My FM receiver uses a series of 5 diodes to indicate signal strength with 3 to 4 normally displaying for the stations I listen to. Simply plugging the system into the dedicated reseptacle pushed 9 out of 10 of them to 5 LED's!

[analog97]

I think if you put in a "twin" breaker in the panel, each hot leg comes off different sides and the result is each circuit is 180 out of phase. That is why it seems to me it would be preferable to use two single breakers, one on each side of the panel. Maybe I missed something in DarqueKnight's posts about this.

I meant to say it would be preferable to use two single breakers, BOTH on the same side of the panel.

[DarqueKnight]

Metal outlet boxes or Plastic?

BX or Romex?

I used plastic boxes and Romex, but I wonder whether metal outlet boxes and the metal shielding of BX cable would provide better shielding against noise. It is something worth investigating.

Since I will be adding a sub-panel for my new audio room and all new circuits I want to do it correctly. Does PS Audio have recommendations on what type of Panels, Wire & outlet boxes to use?

No, but if you want to go upscale, the nice people at Cardas have some $11.50/foot UL rated 10AWG x 3 in-wall for you.:) Also, Isoclean makes a $5,000 100A audiophile grade breaker panel for your listening pleasure.

It would be wonderful if the makers of such products would provide some quantitative performance analysis comparing them to the regular residential grade stuff, but that is probably too much to hope for. Stepping out on faith to try a $100 outlet is no big deal because it requires minimal installation effort and can be easily removed and returned. If the expensive in-wall wire and electrical panel does not work out...there's going to be some drama...emotionally and economically.

Take lots of pics of your construction project.

[DarqueKnight]

One question here about electrical phase. The 2 hot legs of a standard electric panel are each 120 Volts, but they are out of phase by 180 degrees. That is why (as I understand it) you can get 240 Volts between them. So, if I or anyone else wants to run 2, 20 amp circuits for his system and you put both circuit breakers on the same side of the electric panel, I think the result is that each will be out of phase by 180 degrees. I really don't know what difference this would make, but my question is whether it is better to run each circuit from the SAME panel hot leg, rather than one from each side? Any electricians or EE's out there? Maybe I missed something?

I think if you put in a "twin" breaker in the panel, each hot leg comes off different sides and the result is each circuit is 180 out of phase. That is why it seems to me it would be preferable to use two single breakers, one on each side of the panel. Maybe I missed something in DarqueKnight's posts about this.

I meant to say it would be preferable to use two single breakers, BOTH on the same side of the panel.

My secondary distribution panel is arranged in two vertical columns of breakers, with odd numbered breakers on the left and even numbered breakers on the right. In each column, the successive breakers alternate legs. The first two positions, 1 and 3, on the left column have a dual breaker (30A, 240V) for my clothes dryer circuit. When I added two additional AC circuits for my monoblock amps, I put each circuit on a different leg.

I would also recommend putting the analog and digital circuits on different legs, unless you are using some type of power conditioning equipment for your source components that does the isolation.

[analog97]

When I added two additional AC circuits for my monoblock amps, I put each circuit on a different leg.

This means that each monoblock sees an AC phase 180 degrees apart. This was at the heart of my question. I am uncertain if this is good. I was thinking it would be preferable for each monoblock to see the exact same AC phase. The way to do this is not to use different legs in the panel, but the same leg for both circuits.

[DarqueKnight]

This means that each monoblock sees an AC phase 180 degrees apart.

It would be bad if the audio signal for each channel was 180 degrees out of phase.

[analog97]

DK, it does appear that this is the case. It's an easy fix to move the breaker to the other side of the panel. Let us know if you detect any difference. Also, I now wonder whether any measurements taken in this post could have been affected. It seems the only fair way to detect differences in powercords or whatever would be to make sure that each "sees" the same hot 120V AC leg. Each leg is out of phase 180 degrees and travels over separate power lines for miles. Seems to make sense each 120 V leg would display its own, unique noise. Hmmmmm.

[DarqueKnight]

It would be bad if the audio signal for each channel was 180 degrees out of phase.

DK, it does appear that this is the case. It's an easy fix to move the breaker to the other side of the panel. Let us know if you detect any difference.

Seems some clarification is in order. You seem to be confusing the phase relationship of the left and right audio signals with the phase relationship of the left and right power signals going to each amp. The AC power going to the individual amps can be 180 degrees out of phase without diminishing the quality of the audio signal because the AC is rectified to DC by the amp's power supply. Of course, DC has no frequency and therefore no phase. Thus, there is nothing to "fix".

For additional insight, consider the following:

A. I once ran my entire two channel system off one AC circuit. Putting both JC 1 amps on their own dedicated circuits, on different phases, resulted in much better sound. So much so that I installed two additional AC circuits, on different phases, for my home theater system. That experience alone, and in conjuction with the reports of others who have done the same thing, informs me that I did the right thing for my electrical environment.

B. I did not need to do any reconfiguration at the breaker to learn if having both monoblocks on different circuits, but the same phase, would be better. There are three dedicated AC circuits feeding my two channel system: the original circuit and two additional ones. The original circuit and the left side new circuit are on the same phase. The additional right side circuit is on the other phase.

Just for fun and edification, after the two new circuits were installed, I compared the following configurations:

1. Everything connected to the original circuit (standard configuration for a long, long, time).

2. Left power amp, preamps, and turntable connected to the new left side circuit and right power amp and sacd player connected to the new right side circuit (configuration used prior to installing an AC regenerator for the source components).

3. Source components connected to the original circuit and both power amps connected to the new circuit on the same phase as the original circuit.

4. Source components connected to the original circuit and both power amps connected to the new circuit on the opposite phase.

5. Source components connected to the original circuit and each power amp connected to one of the new circuits (current configuration).

All configurations sounded good, but there were some differences:

Configuration 5 sounded best.

Configuration 2 sounded next best.

Configurations 3, and 4 sounded the same, but better than configuration 1 and not as good as configuration 2.

Configuration 1 ranked last in sound quality.

Of course, a particular individual's results will vary depending on their particular equipment and electrical environment. Some people have experienced ground loops when they split their audio gear between phases. My result was better sound with a lower noise floor.

There has been some discussion on this topic on the Audiogon and Audio Asylum forums and those might be of interest to you. There are adherents to both methodologies.

C. Both legs originate from the same source and the common mode noise on both legs is the same. Since both legs are 180 degrees out of phase, putting each monoblock on a different leg cancels the common mode noise.

Also, I now wonder whether any measurements taken in this post could have been affected. It seems the only fair way to detect differences in powercords or whatever would be to make sure that each "sees" the same hot 120V AC leg. Each leg is out of phase 180 degrees and travels over separate power lines for miles. Seems to make sense each 120 V leg would display its own, unique noise. Hmmmmm.

You are confusing transmission lines from the generating plant with distribution lines to the home. High voltage power is carried from a power plant on three phase lines whose individual voltages are 120 degrees apart. The distribution lines to individual homes is typically single phase ("split phase") 240 V service that is split by a transformer into two 120 V lines 180 degrees out of phase.

[DarqueKnight]

Each leg is out of phase 180 degrees and travels over separate power lines for miles.

My neighborhood is served by underground power facilities. The 120V/240V transformer that feeds my home is enclosed in a little green box that sits on the ground and it is only 33 feet from my meter.