Dedicated vs. 'regular' AC power.. and cords

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Carlman

Dedicated vs. 'regular' AC power.. and cords
« on: 16 Apr 2005, 03:32 pm »
Ok, so.... I've always been a big believer in a dedicated outlet for your main system.  It makes things easier all the way around and generally improves sonics to varying degrees.

I had an electrician perform the work, mainly because it was $250 or so and one spot required special tools.  He installed a new 'Square D' breaker, at the top of the box.... however, the top is farthest from where the main power comes in.... so, I may change that.  He used 12ga Romex (it had a yellow jacket) and it runs straight from the breaker to the sound room outlet. (no cuts/boxes)

So, with a 12 gauge dedicated outlet, I was expecting a little improvement but not a revelation... my system already sounds pretty good.  However, for the price of a good PC, I figured this would be money better spent.

However, in this application I noticed a degradation in some areas... specifically, a lack of nuance or 'finesse' with the dedicated outlet.  It seems like the highs or upper midrange now has a little harshness where it didn't before.

What's cool is that the old outlet is still available to A/B these things.  They both use the same Cooper 5252 outlets... However, I may have treated the older one with some CAIG contact cleaner... I may try that too...  But, when I went back to the older outlet, that finesse was back.. and little details seemed more evenly presented.  With the newer dedicated outlet, there was maybe a little more bass definition and maybe better palpability in vocals.. but I don't know... it was a weird difference I can't put my finger on... (yet)

In any case, even without little tweaks and moving around the breaker, I would've thought there would have at least been a slight improvement... and not a small step backward.  Either the better power is revealing other issues in my chain or I need a better power cord... or whatever...

So, Why not experiment with power cords?  I have 2 DIY cords, a Volex, and a Kimber.  The first I tried was the Volex on the DK integrated and the Kimber on the source (an Audio computer).  This produced the most glare in the upper midrange.  Next I tried the DIY Belden 19xxx? (not sure) recipe that's been cryo'd... I have 2 of these.  This made the background a little quieter and improved realism a little.  Then I tried my Belden 83802 cord which sounded different but not better or worse... just different... maybe a little more forward in the midrange?

I have always had a hard time hearing differences in power cords... However, with the dedicated outlet I went from hearing no difference to hearing some difference... still very slight... but it's there.

So, now I'm not sure what to do... spent $1500 on a BPT.. ugh, I don't have that.. or go DIY and make a transformer and do balanced output...  get some better power cords... no $ for that...

Or just go back to the non-dedicated outlet.  :lol:

Either way I go, I've realized plyaing with power sucks.  I have no idea what I'm doing or why these changes exist.  So, be careful what you wish for... and pay for... ;)

PhilNYC

Dedicated vs. 'regular' AC power.. and cords
« Reply #1 on: 16 Apr 2005, 03:55 pm »
Carl,

How did you handle the outlet grounding?  Is it an isolated ground back to the circuit breaker?

FWIW - My experience with my recently installed dedicated outlet has been very satisfying.  Not only does my audio system sound better (to my ears), but my AV system in my other room is sounding better now on its shared circuit (now that I've taken the audio system off that circuit)...

Carlman

Dedicated vs. 'regular' AC power.. and cords
« Reply #2 on: 16 Apr 2005, 03:57 pm »
Quote from: PhilNYC
Carl,

How did you handle the outlet grounding?  Is it an isolated ground back to the circuit breaker?

FWIW - My experience with my recently installed dedicated outlet has been very satisfying.  Not only does my audio system sound better (to my ears), but my AV system in my other room is sounding better now on its shared circuit (now that I've taken the audio system off that circuit)...


It's wired like any other circuit in the house... there's 3 wires from the outlet to the box and all are connected like all the others... the bare copper ground goes to the spot with the rest...  so, I don't think it's 'isolated'... How would I isolate it?  I have no other ground that's not common.

-C

PhilNYC

Dedicated vs. 'regular' AC power.. and cords
« Reply #3 on: 16 Apr 2005, 04:06 pm »
Quote from: Carlman
It's wired like any other circuit in the house... there's 3 wires from the outlet to the box and all are connected like all the others... the bare copper ground goes to the spot with the rest...  so, I don't think it's 'isolated'... How would I isolate it?  I have no other ground that's not common.

-C


An isolated ground doesn't mean a separate ground...but basically it takes the ground from the outlet all the way back to the panel by itself (not grounded to the outlet box).  To do it, you need an "isolated ground" outlet, like a Pass&Seymour 6200/6300.  You should also make sure that the circuit breaker that is used in your breaker box is "higher" than your big circuits (eg. washing machine, fridge, etc)...

Here's more info:

http://www.liebert.com/support/whitepapers/documents/sl_24275.asp

Steve

Time
« Reply #4 on: 16 Apr 2005, 04:59 pm »
Dear Carl,

     I was wondering how long the dedicated line has been breaking in, been installed?

audioengr

Dedicated vs. 'regular' AC power.. and cords
« Reply #5 on: 16 Apr 2005, 05:58 pm »
Steve's probably nailed it.  All of the wire and the outlet needs to break-in.  Make sure that the wire is screwed to the outlet screws and that the copper is clean before attaching - use steel wool.

BTW - if you are putting in a new circuit, you should really put in plastic conduit and then twist separate solid THHN wires.  Much lower inductance than ROMEX.

bubba966

Dedicated vs. 'regular' AC power.. and cords
« Reply #6 on: 16 Apr 2005, 06:42 pm »
Carl,

When I instaled a dedicated outlet (10/2 Romex & Eagle/Cooper IG8300 outlet) I experienced the same sound you did. After a couple of weeks of break in, it smoothed out and sounded much better.

I seem to recall reading in another thread that you were having this line installed yesterday. If so, give it a couple of weeks to a month of use then try your A/B test with the old outlet again.

ctviggen

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Dedicated vs. 'regular' AC power.. and cords
« Reply #7 on: 16 Apr 2005, 07:09 pm »
Concerning that Liebert article, I think that would provide less noise (EMI/RFI/whatever) getting into the line, so that would be good.  However, it wouldn't do anything regarding noise already on the line.  It's going to be something that depends on where you are.  If you're in a highly populated area where a lot of EMI/RFI can be coupled to the AC, then I think it's a valid way to do things.  It's also something to consider should you buy a house or build a dedicated room.  I'd like to try this out, but until I decide to tear up drywall, I can't do it (I installed a dedicated outlet myself, but I ran the wire about 5 feet from the outlet into the breaker box; the wire literally runs into the front of the breaker box, and will remain that way until I decide to remove and reinstall drywall).

Carlman

Dedicated vs. 'regular' AC power.. and cords
« Reply #8 on: 16 Apr 2005, 09:23 pm »
Thanks for the thoughts and tips.

My comments were based on the outlet being installed for approximately 15-30 minutes before listening... I didn't think an outlet and Romex really needed burn-in... I'll report back in a couple of weeks of constant playing with a second A/B comparison.

I didn't want to do the THHN wire because I didn't want the added expense of time and such... and how would get all that conduit home?... just too much work and money to justify in a house where I don't know how long I'm going to live and in a sound room that's not really optimal.

When I build my next house it will have a dedicated sound room that utilizes a much more 'Full-Ass' (to quote NathanM) implementation.

Thanks,
Carl

cryoparts

Dedicated Circuit
« Reply #9 on: 16 Apr 2005, 09:34 pm »
Carl,

Plug a fan into that new dedicated line and let it run 24 hours a day for a few days.  After about 150 hours, things will smooth out nicely.  Give the new circuit 250 hours or so for full "break in".

I think the Cooper 5252 has nickel plated brass contacts, you might want to look into an unplated receptacle as well as it will sound smoother.

Regards!

Carlman

Dedicated vs. 'regular' AC power.. and cords
« Reply #10 on: 16 Apr 2005, 09:47 pm »
Sometime next week I'll be getting a PS Audio powerport (from Bruno) to replace the Cooper.  Bruno's currently using it so, I know it's 'burned in'.  The Cooper is one I had lying around... and I didn't want to pay the electrician more $ for an identical outlet.  I bought it thinking it sort of looked like a P&S 5262 but I've since learned it's not the same.  

I'll see if I can find a fan.

Thanks again,
Carl

TheChairGuy

Dedicated vs. 'regular' AC power.. and cords
« Reply #11 on: 17 Apr 2005, 01:44 am »
Carl - fyi - the PS Audio Power Port is also nickel plated.  As everything imparts some signature to the sound, just be aware of this.

I changed the $9.80 Lowe's Hospital Grade (orange color) Eagle outlets out with the Power Port and didn't hear a whit of difference; but that's me.  The real difference was changing out he $.50 one with the Lowe's unit...a very worthy $9.80 and 30 minutes wiring it was.

I don't have a dedicated line in this house...but I'd figure nickel vs. copper. vs. gold plated vs. silver plated and/or cryo'ed  might make more of a difference with your set-up now.

Adz523

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Dedicated vs. 'regular' AC power.. and cords
« Reply #12 on: 17 Apr 2005, 02:46 am »
Quote from: TheChairGuy
I changed the $9.80 Lowe's Hospital Grade (orange color) Eagle outlets out with the Power Port and didn't hear a whit of difference; but that's me.  The real difference was changing out he $.50 one with the Lowe's unit...a very worthy $9.80 and 30 minutes wiring it was.
Quote


I suspect the true difference between the $9.80 Lowes and the $49.95 Power Port is not sonic (at least not discernable to the human ear) but really build quality and longevity at the end of the day.

PhilNYC

Dedicated vs. 'regular' AC power.. and cords
« Reply #13 on: 17 Apr 2005, 02:58 am »
Quote from: ctviggen
Concerning that Liebert article, I think that would provide less noise (EMI/RFI/whatever) getting into the line, so that would be good.  However, it wouldn't do anything regarding noise already on the line.  It's going to be something that depends on where you are.  If you're in a highly populated area where a lot of EMI/RFI can be coupled to the AC, then I think it's a valid way to do things.  It's also something to consider should you buy a house or build a dedicated room.  I'd like to try this out, but u ...


This is true.  I have an Audioprism Noise Sniffer (a device that you plug into an outlet, and it has a speaker that will "audiblize" the noise on the line).  Plugging it into my dedicated line, there is just as much noise as on my non-dedicated line (although at a slightly different pitch).  So there must be a lot of noise getting into the AC line from outside the house.  So I still use a power conditioner on the dedicated line.

However, I do notice that my voltage is higher and more stable than on my non-dedicated line.  On the non-dedicated line, my voltage varies from 120v-124v over the course of a day.  On the dedicated line, it is a very stable 124-125v.  And the sonic difference is far greater than what I get when just using a power conditioner on the non-dedicated line.

Kevin P

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Dedicated vs. 'regular' AC power.. and cords
« Reply #14 on: 17 Apr 2005, 03:04 am »
I'd vote for staying reasonable.

Dedicated line:  Yes

Seperate Ground:  Yes (if it is allowed by code).

Good quality outlets:  Yes   P&S 5262-AW

Balanced Power & RFI filters where needed:  Yes... don't spend much more than $1200


Spend the rest of your budget on the room.

PhilNYC

Dedicated vs. 'regular' AC power.. and cords
« Reply #15 on: 17 Apr 2005, 03:13 am »
Quote from: TheChairGuy

I changed the $9.80 Lowe's Hospital Grade (orange color) Eagle outlets out with the Power Port and didn't hear a whit of difference; but that's me.  The real difference was changing out he $.50 one with the Lowe's unit...a very worthy $9.80 and 30 minutes wiring it was. .


A little off-topic...but I did a little research, and found out that "Hospital Grade" primarily refers to two things; that the outlet is tamper-proof, and that it is fire-proof.  Nothing about being Hospital Grade has anything to do with contact strength, purity of materials, etc.

The P&S 6300 that I have is "Specification Grade".  This also apparently also doesn't mean a whole lot (there is no industry standard definition of "Specification Grade"), but outlet manufacturers use the term to designate some higher level of performance from their general outlets.

FWIW - the P&S 6300 has the strongest grip I've ever seen...

Kevin P

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« Reply #16 on: 17 Apr 2005, 03:40 am »
Yes... hospital grade is simply one of those meaningless specifications.   Sort of like mil spec ratings.   I think the main reason that there was a hospital grade was due to the danger of sparks caused by plugs pulled from live applicances.   Hospitals have lots of pure oxygen on hand and sparks + pure oxygen is a dangerous mixture.   Looking at hospital grade outlets I'm not sure how their construction helps in this regard.

lupodwdm

Dedicated vs. 'regular' AC power.. and cords
« Reply #17 on: 23 Apr 2005, 06:18 am »
Quote from: Kevin P
 I think the main reason that there was a hospital grade was due to the danger of sparks caused by plugs pulled from live appliances.   Hospitals have lots of pure oxygen on hand and sparks + pure oxygen is a dangerous mixture.   Looking at hospital grade outlets I'm not sure how their construction helps in this regard.


Your %100 correct.   This is the only real reason.  Sparks + O2 = Bad Day. :cry:

I was the other person who posted a thread the other day about a dedicated run from my breaker.

My electrician friend ran yellow romex to a 20 AMP breaker and installed a hospital outlet next to my system.  In my experience, the effect was HUGE and immediate.  A few days later I had one of my listening buddies over and asked him to switch the plugs on me to and from the new dedicated/ old shared outlets when I was out of the room.  The way my system is set up you can't see which one the power conditioner is plugged into unless you look behind everything.

My point is that I was right in identifying 7 out of 8 times using the same DVD-A disks.

Granted, the old shared wiring was installed in 1976 when the house was build and shares it's run with 6 other crappy outlets in the living room with various lamps and junk plugged into them.  Also, my sub was on this same circuit.

Now the sub is plugged into a new higher-grade outlet but still on the shared circuit, while all of the components and amp are going through my power conditioner into the dedicated run.

The way I could tell the difference was during the very dynamic passages.  When everything was on the same circuit the sub and the 7-channel amp were fighting for current.  Now, the impact of the sound is incredible.  No more sounding compressed and a little bright when it got loud.

Trust me, being involved in physics for a living I am VERY skeptical about a lot of the "break In" and "dedicated" things out there, but I know my ears VERY well and I can tell the difference.

I think the reason you may not be hearing such a drastic change in sound is due to you having a pretty good run to start with.

ctviggen

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Dedicated vs. 'regular' AC power.. and cords
« Reply #18 on: 23 Apr 2005, 11:41 am »
This definitely depends on a number of factors.  For me, I went from a non-dedicated outlet to a dedicated 2-outlet box with cheap outlets, then switched the outlets to cryogenically treated, silver coated $50/each outlets.  I can't honestly say I heard a difference.  However, the original circuit runs about 6 feet to the breaker box; the new circuit runs basically the same length.  So, either way, I'm getting power that's about as close to the breaker box as you can get. Also, this house was built in 1986, so the wiring is (basically) up to today's code.

Carlman

Dedicated vs. 'regular' AC power.. and cords
« Reply #19 on: 23 Apr 2005, 02:40 pm »
My house was built in '99 and the electrician did a pretty good job and used a nice breaker panel.  The circuit I was using had about 10 other shared outlets (all less than 49 cents) but they had nothing plugged into them.

My goals were to reduce/elminate RFI by not having lots of connections in the loop.  So, the cable only has bare metal at the 2 ends vs. lots of places.  Anyway, that's my thinking.... could be flawed but I don't claim to be an electrical engineer.

The surprising thing is that the tube amp I'm auditioning got loads better with the dedicated outlet.  I was shocked. har har.  Seriously, the slam and dynamics improved.... as did the imaging... and then all of that improved again when I replaced a pair of sub-standard tubes in the amp.  Wow.  

Now that the outlet has been 'burning in' for a week on the tube amp and some other stuff, it's smoothed out a bit.  I plan on doing and A/B comparison later today.

-C