Dedicated power circuits

I desigbed and build that all in one AudioUltra panel.  I have modified it since inception.  It can't be beat when installed  in the right application.  That application is on a wall between monoblock amps and subs.  I don't use a power cord.  Its bolted directly to a feeder wire and capable of passing 225 amps. 

An all in one Torus distribution is great, but not so great.  Its a better suited product in recording studios where many have been installed.  There are much better ways to integrate a Torus in a residence. 

I had to have the second phase run at Fremers because I could not get a letter from SqD  saying a Square D subpanrl rated 120/240 was suitable for 120 only.  In response to this, I manufacture a 225A all copper panel with a UL label rated for 120 volt only.   Yes you only use one phase. 

I went back to Fremers and changed out that panel in the image above. .  I now rework those SqD QO MLO 125 to 200A subpanels with damping compounds and install all copper neutrals and grounds.  Its a shockingly good panel for the money when rebuilt.  Stock they are little better than a couple others.  There is crap ou there like Homeline and Eaton/Siemens/CH BR style.  Waste of money.  And they limit performance.  

The primary feed from the utility to the receptacle in the wall can be very sensitive to how the wiring is installed.  The best electrician out there is going to do it wrong  because he does not have experience powering something as sensitive as an electron microscope.  Thats your stereo.  He will do what all electricians do, meet code minimum.  Anything more in their mind is a waste of money.  They don't get it.  That twisted wire at Fremers.  I grain orient it.  Tell an electrician that and their eyes glaze over.  Tell that to a cable manufacturer and they will acknowledge you know one of their secrets.   When wire is drawn through dies to size it, it gets a grain.  I have heard it called a Chevron.  Its audible and measurable.  I am the only person in the US I know of who is talking UL THHN/THWN solid 10 awg and determining its grain, then orienting all 3 hot, neutral and ground before installation.  Others have stuck wires in a drill and twisted them.  My tools are more clean and precise.  I built a custom bobbin and twist the wire 1 turn every 2 inch.    I am soon going to Cryogenic immersion bath this wire. 

I don't like MC cable or wire in a steel pipe.  I use it when I have to such as in NYNY.  Otherwise its a can of worms.  It creates ground loop issues.  It really blocks no RF.  Its there to stop fires as an arch in the conductors rarely propagate ouside the metal case.  Steel will block a small amount of emf from one branch circuit to another.  But the steel case is interacting with the electro magnetic field around the wire and compressing it. In my mind Its not ideal.   But I do need to test it more.

I do not like 8 awg and larger.  MSB may have written a paper saying you want to upsize to larger gauges for longer runs, but every wire is audible.  8 is analytical.   It grabs your attention and makes you aware of different parts and pieces in the music.  Its harder to relax and enjoy.  10 is plenty of current.  Romex is decent wire.  If your on a budget, use it.  Its a little hard and slightly analytical,  but not like 8.  Romex is great for subs.  8 can be too.  They speed up the bass.  Grain oriented twisted is more whole and complete in tone.  Its easier to digest the whole of the presentstion and relax while listening.  Its a little fuller, but looses no resolution. 

The all copper panels I mentioned are nice as you eliminate the galvanic reaction between the copper and aluminum.   Its audible.  Its heard as a sleigh  veil and haze.  A small amount of lost resolution and softening of the music.  If you have SET amps and horns, you might find it tames some of their potential "Hot" dynamics.  It could be consodered a tone control.  I prefer to rid noise and work on taming the speaker/room issues in the room.  Not in the electrical infrastructure.   

Rex

How many wires are in 10/2 and what are they.

Southwire Armorlite 125-ft 10/2 Solid Aluminum MC Cable

You sure you want to recommend this cable. Think of all the issue you are creating. I would never use it. Its what I removed from Fremers that was causing lots of issues.

And I'm pretty sure its not twisted anymore.  Most all that stuff is strait transmission line.  Its held together so the impedance/capacitance is stable.

If your really concerned about rejecting noise, put an isolation transformer in for amps.  Size it to feed the whole system.  Or use an Audio Quest type filter on the front end and amps to the wall.  Either of those solutions will get rid of a lot of noise.  MC does not get rid of any noise.  The aluminum may block a small amount of RF on the branch only.  Aluminum does not do much for EMF when cables are places side by side.

I personally say stick with Southwire NM cable or spend more and get grain oriented twisted. 

Remember the Dead Poets Society when Robin Williams told the kids to stand on their desks.  To see the world from a different perspective.  I don't even know if you all have put your boots on the ground.  Wiring an AV room is not the same as wiring a 2 channel audio room.  Proper grounding has little to do with the electrode in the earth.  You don't use metal encased wire with a hot, neutral and ground.    I don't care if its AC, MC or Steel/Aluminum pipe and wire.  If you wrap you wire in metal you have to be very careful in how you do it.  If you make a single mistake, you will have a very loud ground loop.

Many recording studio are wired with metal raceways.  And many of those studio have a large isolation transformer that feeds everything.  But the guy who designed the infrastructure is many times at the site during installation to oversee the project and make sure the electrician does it right.   An electrician is your worst enemy when it comes to powering your audio system.  They will ignore the spec and drawings, say they know best, then ask for a change order to remove and replace materials they installed incorrectly.  Your much safer using NM.

And, you have to make a shop where you can limit variables and listen to what you preach.  You have to go through 5 or 6 homes and step by step change out 1 variable at a time, then listen and learn.  Let it sit for a couple weeks and get the owner feedback.  Then go back and make 1 and only 1  change, then listen again and let it marinate.  I have been fooled myself.  I made a change to feeder ground and was all smitten with the resultant bass.  The owner told me 3 days later to rip it out.  It was all wrong.  He could only turn the stereo on for about 1/2 an hour, then he was completely unsettled and turned it off.  I changed it back and he said it was night and day better.  He was back to listening for hours on end.  I shared the experience with an industry professional and he explained why what we heard happened.  WIRES HAVE A SOUND.  Every one of them.  Maybe your a denier and think every power cord sound the same.  If that is the case, then why are you even arguing.  It doesn't matter.   If you do believe power cords have a voice, then why wouldn't 40 feet of wire in the wall also have a voice.  Technical jargon is just that.  Its indispensable to be educated, but you have to listen to what you do.  I am constantly learning.  I'm not perfect.  I have made mistakes and stumbled.  Like the ground above.  But hey, the internet if full of people saying oversize your grounds.  So I tried it.    But every time I do experiment I know more.  At times I go back to projects I did in the past and refine the installation to get a little more out of it.  Like I said earlier, the NEC is a minimum.  Just because it meets code, does not mean its anywhere near as good as it can be.

If you decide to put some holes in your walls and bring 5 or 6 different wires from your distribution panel out to your rack with the same termination on the end to listen, I would love to hear your impressions.  I like to do this with my amp and my DAC.  As well as phono preamp at times.  And don't forget to let it rest in your system for a couple weeks.  There is a big difference between back and forth listening and living with something for a while.  What might sound WOW to you at the moment might end up quite grating over time.  I find 24 hours or constant play with maybe 2 or 3 on off cycles is enough time to get a wire stabilized to hear what its doing. 

I found some MC in my shop.  Its 1 twist every 5.25 inch.  I twist 1 twist every 2 inch.

Well, I typed for 1/2 an hour then stepped away and it all disappeared. 

I disagree with most everything Minorl says. 

Keep it all on one leg. It matters. It not about the noise. If you have a good system, say AR Ref amps and an Esoteric CD player, you will hear it.  It will be more clean and clear.  If you have a Cary SLI80, you might not hear it.  But you will still notice a 10AWG dedicated circuit vs a 12 AWG feeding the rest of the living room.  

I also have not been able to validate putting lights or motors on the same leg as audio is detrimental. The noise is also on the neutral. You can’t hide from it.  I have tried this on many systems before I gave up on it because no one ever heard it.   Make sure to use a quality dimmer such as a Lutron Maestro. That will filter most of the noise.  I do put motors on a separate leg to reduce startup voltage sag on the audio phase.

I do like a good filter. But the only one I have found to work to my satisfaction is a large Torus transformer that has everything on it. Including your modem, router and switch if you stream. I don’t like most other filters. They either collapse the sound stage or create an artificial "Black".

If you don’t want to filter your audio, you segregate your power with subpanels and you filter the noise from your house. But what are you really doing. Not much unless your off grid "Island".  And if your off grid, I am still going to suggest you put a Torus onto the circuits feeding the audio to filter the inverters high frequency noise. As well as any RF that is attaching to the power wiring. If RF is attaching to the phono cartridge, tone arm wire or case of the phono stage itself, you cant do much other than get a good phono preamp that is good at rejecting the noise and not letting it modulate into the power supply.

If you happen to have a very large estate with pools and fountains, security systems, a server farm and a high end audio system, then segregating power and filtering the noise from getting back to the audio becomes something to consider.  You probably have a dedicated utility transformer so your filtered from the street noise.  You may want PFCC attached to a subpanel feeding the motor loads.  You may want a UPS attached to the server farm and security system.  You may want critical power with battery backup for light and refers in power outages.  Most people don't have this.  They share power with 5 neighbors on one transformer.  Your getting all the noise from their dirty devices.  So trying to segregate and filter your own dirty devices is a loosing battle.  Your best option is to filter the line to the audio equipment.

It’s not hard to make the comparison between 1 leg and 2 when you have gone through multiple systems and step by step made 1 change then listened.  It makes a difference.  And anyone that is caught up on just focusing on the phase line and voltage that is regulated by the equipment power supply is missing everything going on with the neutral and ground and how those 2 play into the system.

Again, you can not hide from power line noise by selecting a phase.  The noise is on the neutral.  Unless the noise is from a 240 volt motor, in which case, it’s on both phase, so again you can not hide from it.

Yes the power supply in the equipment regulates the incoming 120 volts to something else.  But most equipment also has some connection of the equipment power supply of the signal ground that is tied to the chassis ground.  So the signal is tied to the 120 volt power grid.  I have heard it.  Others have heard it.   Just do it.  In my opinion, there is no reason to not use 1 phase.  There is 0 evidence only 1 phase causes any issues.  So why fight it?  To make a point?   If that is the only reason you are arguing, your helping nothing. 

And, people here seem to think it’s great to put metal clad cable in and tie the ground to the shield of the cable which then allows the shield to become an antenna.  Or at a minimum you have introduced a ground loop because the impedance of the shield and the copper wire are different.  And before some "Engineer" gets on a rampage, let me say I have removed more than one annoyingly loud ground loop by eliminating 3 wire MC and replacing it with Romex. 

I don't have an engineering degree, so I don't talk as technically proficient as others.  What I have done is consult with many engineers, nuclear and NASA scientist. I have read a lot. I have taken specialized classes on grounding.   I have made alterations, observed the result, then sought out knowledge from these type people to understand why I heard what I heard.  I have also wired maybe 100 systems and have a large data base of evidence to back what works and what does not.   I will say again, putting MC into an electrical supply is a receipt for disaster unless you are very cautious.  IF you only ran 3 wire MC with a hot, neutral, ground and metal shield, you’re likely to have noise and/or ground issues.  If you ran 4 wire and don't use an isolated duplex on even 1 outlet, you may introduce ground and noise issues.  Even 4 wire MC is not a full proof way to eliminate noise.  The jacket is an antenna for RF.   It really does nothing for audio performance.   Commercial facilities use metal for fire protection.  Not because it has better performance characteristics.  Just like your house has AFCI on all the breakers.  They don't make your computer work faster or stereo sound better.  To that matter, I have sat and listened with others and you can hear an AFCI breaker as a small veil on the music.  They hinder audio playback.    But they extinguish arc fires before they propagate to the rest of the house and burn the building down.  They do a great job at that.  As do metal raceways. I have been in a room when the switch was thrown and a faulty piece of MC arched inside the cable jacket.  It was a very large boom and smoke smell.  It took a while to find the fault as the case was fully intact.  Just a small discoloration of the jacket under the flash.  No flame left the jacket where it could ignite combustible materials around it.  That is why you use metal jackets.  It’s fantastic fire protection.

The only shielding that blocks RF to any degree is a copper pipe.  No one runs wire in copper pipe.  Steel and aluminum don't really do anything towards blocking RF.  They do block EMF.  But cable management eliminates issues associated with EMF radiating from your power cable and contaminating other circuits in close proximity.  That's all metal is doing for you.  Maybe you want to run the rest of the house wiring that is in close proximity to your audio outlets in metal.  That is a good solution.

The only real block to RF is putting something such as a Torus Isolation transformer on your rack.  The best location for a isolation transformer is on the rack.  The second best is within 10 to 15 feet of the rack.  After 40 feet, you have potentially lost much of the RF noise mitigation as it has reentered the circuit again.  Metal won't keep it out.  You can coat a room with Faraday shield.  But it’s very hard to do correctly. I have heard of one audio room I want to visit and been in a commercial room that was RF treated.  The one I was in was a government building where they wanted to house sensitive equipment.  My phone still partly worked.  It was very intermittent and definitely impacted it.   But it was not 100%.  I would like to get in the audio room with my RF sniffer and see what is still there.  RF is an interesting phenomena.  In my room, my meter reads about 1700 near my rack.  Even with the equipment turned off.  It’s not my audio equipment.  Walk 24 feet out of the room and into my hallway and it reads about 70.  It’s a massive drop in only a few feet.  Directly above my audio room in a bed room the RF is around 1700.  Something about that side of the house.

I just came back from a work trip where a client was crying about a radio station bleeding through his speakers.  I was confident it was not my power supply, but I had to go check.  In the end through various processes of elimination an use of filtration, I was able to validate his system preamp was a mess of noise and his phono preamp was not filtering out the RF from the cartridge, tone arm, phono pre enclosure.  It is my experience through many people asking for my assistance to eliminate some sort of noise, I find the issue is the audio equipment itself that is the culprit.  I have seen it with 3 year old 40K monoblocks to brand new $20K phono stages.  I have never seen a clients noise issues emanate from a well designed electrical infrastructure using NM cable.    Having said that, I have dropped  Torus Isolation transformers on peoples racks and 2/3rds of people end up buying it.  I sold 2 out of 3 on this last trip.  There is a ton of noise on the power line. But it’s not noise you notice as a hum or radio.   It’s a hazy veil most people don't notice.  They just keep buying new gear trying to get better performance.  Once you eliminate the power line noise, the music becomes more clean and quiet.  Not black.  The room feels more calm.  Details are more present in the recordings and the bass becomes tighter and more integrated with the whole.  The music is more natural.  There is noise on your power line.  Lots of it.   But you’re doing nothing to get rid of it by wrapping a few feet of your infrastructure in steel or aluminum.  Those that say shielded wire does not matter because there are hundreds of miles of wire that are exposed to noise injection have a very valid point.

FWIW, that radio station bleeding out my clients speakers.  You won’t fix that with an isolation transformer.  You won’t fix it with any power line filter.  You might fix it with about $25K in Faraday shielding around the room.  That includes over windows, in doors, under the floor.  Everywhere.  You have to encapsulate the entire room.  Or the entire rack.  It’s possible a system set in a closed cabinet that is completely shielded will work.    And then it’s a maybe.  Better to get audio equipment that has a power supply designed to reject RF and not modulate it into the power supply of the audio equipment. 

Here is a good read.  More important, go to the References and read all of those.  I have read a lot of the materials noted in the references.

https://cdn.cableorganizer.com/old-images/midatlantic/PowerSolutions-middle-atlantic.pdf

In summation, if you want the best power for your audio

Ground Correctly

Use all copper panels and wiring.  This means the neutral and ground too.

Segregate power

Use an isolation transformer

Use NM #10.  Better to use twisted wire.  Better to use grain oriented twisted wire.

If your dead set on using metal encased wire, use an isolated ground system

This is a very high level list.  It lack all detail on how to set the infrastructure up properly.  It’s basically a one line.

Jai, I replace MC because of ground issues.  I experience it in the field.  I really could care less about EMF issues.  You can deal with that in the field.  More EMF issues arise behind your rack than in the wall.  If you know how to run wire.   EMF is teally one of your lesser issues.  

AQ, Shunyata, Isoteck, Torus are all filters with their own technology.  And Voice.  I was pretty pissed when TAS did an article on power conditioners and failed to mention an isolation transformer.  Isolation transformers are in most every recordijg studio around the world for 2 reasons.  One they work.  2, Art kelm who specifies that work finds they work best and uses them.  I like them as I have never heard one do negative things.  Only positive.  And I can feed any amp.  I always am aware what any of the other filters are doing. 

If you hear noise out a speaker, that is ground or equipment issues.  Its not dirty power.  You deal with the issues in different ways.  

If you read Arts site, you will see he calls out metal wire and isolated grounds in his cable runs and associated panels.   There are reasons to like metal.  IMO, its not about geometry or performance.  There are other reasons to like it.   But the positives of metal can easily be overcome in NM when installed correctly with the rught materials.  .  And you don't end up with ground issues.  NM reliably works.   Filters are doing a job that addresses noise on the power line proper wiring or metal encased wire do nothing to address.

Interesting question. A little while back I had a project where I had to run 55 feet, 2 circuits in one pipe on the outside of a house. I spun the hot and neutral only on the 2 circuits and pulled the grounds loose in the pipe. I measured 0 mv between any of the neutral to grounds. I was quite surprised at this as I usually see maybe 5mv to 20mv. It has made me want to set up a test in my own system and measure whether it is best to leave the ground loose or twisted. I have also been told by a cable manufacturer to try and twist the ground backwards over the twisted hot and neutral. These are all things to consider.

Another project really surprised me when the Oyaide of about 20 foot runs was giving 72 plus mV between the ground and neutral.

As of this time, I have not had anyone tell me they are experiencing hum issues from induced mV onto the ground. That is not where I end up tracing the issue out. I have had severe hum issues when someone uses MC and goes into one box, then leaves with MC to a second box and lands a second duplex. I have seen this issue twice. I have not seen a hum issue when this is done with NM wire. But I would never advise anyone do as such. There are times when people have budgets and want to shave costs. Even 10 AWG NM is expensive. Every run is about $350 to install if the walls are open. It adds up.

I had another project very similar about 4 months ago.  2 full circuits on the outside of the house in 1 PVC pipe.  About 50 foot run.  My grain oriented twisted wire.  The customer says the system is dead quiet.

I feel there are many types of people out there.  Some are very fixed on the numbers.  They need to see measurements and they base their decisions on them.  I started as an installer.  I worked in the field and followed the plans.  Later I became an owner and designed the plans, as well as installed them.  My foundation is based more on what I find works, than what the numbers say.  That does not mean I ignore or am ignorant to the numbers.   I am aware of them, but I follow more closely what provides results in the field. 

Take for example the above readings with Oyaide.  Not the best.  But that installation was fantastic sounding.  I don't know why the numbers were so high.  But it radically changed the owners perception of how the infrastructure is installed and what/how to use the materials.  It allowed such a better sensed of understanding of his equipment he removed some filtering products from his system.  He later found other he preferred.

I don't find the measurable performance characteristics of a wire as important as what is the wire.  There are other facets of electrical infrastructure that are more impactful than what is the measured mV between the neutral and ground at the duplex.  At least as far as a home audio system is concerned.  If I were wiring a recording studio, I would probably have to re-evaluate my objectives.  With a home audio system, I want the presentation quiet, fee of grain/veil and I want it to sound as natural and close to unamplified instruments as possible.  That's my goal.  

Having said that, I do need to revisit metal encased wire.  Either MC or in a steel pipe.  I also need to revisit how I am twisting the wire.  Do either of these result in  any shift in tonality or noise I can hear.  I have even thought about full immersion cryogenic treatment.  Although a recent conversation with an audiophile I chat with frequently made me question what happens when that wire leaves the bath, then gets thrown around on a floor at a job site, manhandled and pulled into a pipe, then manipulated  in the panel and box.  Have I just cracked free and rearranged all the molecules that were altered in the freezing.   And what about over time.  There are some people saying the magic of cryo treatment goes away over time.  That is why I prefer to find the orientation of the grain from the factory and work with that.

If people want to use metal, go right ahead.  It will probably work out just fine.  Just for goodness sake, don't go from box to box with it.

Per post 1596

Ccomment 1.  Yes, this is where I find metal encased inwall wire to be a benefit. It is very good at rejecting EMI from surrounding wiring.  I know that is not the intent of your comment.  But its the point that EMI radiation is a real issue.  Mostly with EMI getting into signal or speaker cables.  But I am cautious of it with branch circuit to branch circuit as well.

I also find any isolation  transformer has to be located strategically to not interfere with the equipment it is powering.  That is why I prefer a wallmount in the adjacent room.

Per comment 2.  I do not find the sine wave distortion from audio equipment PS to be problematic if you run dedicated line.  That is partly why I strongly recommend multiple circuits.  I do not like a single branch with the assumption it is ridding ground loops.  PS to PS noise can become an issue on a single branch carrying all the equipment.

My comment about the issues being in the equipment itself is exactly that.  For Example, a 4 year old set of $60K monoblocks with buzz at the tweeter.  Owner gets the amps updated and all the buzz is gone.  A brand new $22K phono stage with radio coming out the speakers.  I insert 2 other phono stages and the radio is gone. I did a lot of other test to validate the issue was the phono stage.  $15K SET tube amps with bench tested measured voltage bleeding from the PS to ground creating ground issues.  I see gear itself with issues.  Not the power feeding it.  People don't want to believe their expensive purchases have defects.  But that is many times where "Issue" are traced too.

Updating your power is not about solving issues.  Its all about extracting the maximum performance from what you have.  If you have hum and buzz, its most likely the equipment, not the electrical supply.  If you have a hazy veil, soft uncontrolled bass, fatiguing sibilance, it very well may be the electrical infrastructure.