How do I know if my current AC is good or bad?

DaveC

Industry Expert
Nov 16, 2014
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If you really want to know hire someone to do some tests. Issues with noise on AC aren't necessarily audible as far as pops, clicks, etc. but do reduce resolution and add a "haze".

If you want to try out one of my SurgeX conditioners I do demo them, you just pay shipping. They are used in Carnegie Hall, Yankee Stadium, used by NASA, Lockheed, etc, etc... unlike many conditioners/regenerators you can use them with large amplifiers and they also provide transparent surge protection that doesn't dump excess surge energy to ground.

I'd also suggest a Furutech GTX NCF receptacle to feed your choice of power distribution. I use the NCF receptacles and 20A IEC inlet in my SurgeX and it makes a big difference, so big it's usually shocking. Sorry... ;)
 

microstrip

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May 30, 2010
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I think you are right. One way to know for sure would be to have my AC analyzed with the proper equipment by someone who knows how to properly interpret the readings. My cheapest option at this point may in fact be for me to audition a few of the power cleansing devices in my system from a dealer who allows for this or has a good return option. I am currently intrigued by the PS Audio P20 Direct Stream Regenerator. I see where they have a good trial/return policy.

The question is that there are many problems and many approaches to mains correction. A little knowledge about the problems can reduce the number of devices we should try and help choosing the proper one. No device is perfect - IMHO all of them have compromises. Depending on equipment, reaction of our systems to mains problems can be very different.

The PS Audio P20 seems a very good unit - I know about two local P10 users that changed to the P20 as soon as they compared them in their systems.
 

3rdRock

Well-Known Member
Sep 11, 2018
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The PS Audio P20 seems a very good unit - I know about two local P10 users that changed to the P20 as soon as they compared them in their systems.

I'm curious... do they use the P20 with their amps or only on their front end stuff?
 

Rozza

New Member
Nov 26, 2018
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Have a look on YouTube for videos by Garth Powell of Audioquest, you may not agree with his analysis but after a long time with Furman and Audioquest as their mains products chief designer, he gives an interesting insight as to why mains products work or they don’t. As I say, you might not agree with him but his talks are interesting.

What I have found personally is that no one can advise you. Every condition is unique and the only way you will find out I’d a certain solution works or not is to try out. I started down one route that gave ok results, tried another which was a backward step and then finally came up with my current solution which have a gobsmacking improved. My solution may not be appropriate for you

But to return to your OP, I had voltage swings of about 5%, THD of about 4% and a supplier-earth greater than 1 ohm (now fixed). Some say these aren’t bad figures to start with, but see the Garth Powell videos and you can see that such measurements tell you nothing about your mains in reality

Hope this helps
 

DonH50

Member Sponsor & WBF Technical Expert
Jun 22, 2010
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Note most components have power supplies that isolate the audio from the power line quite effectively. Unless the wall power is really bad chances are you would not notice any additional power filtering in a blind test. (Let the exceptions begin.)

I have UPS units because we have power outages not infrequently (though has been better recently) and I want to be able to ride out a short glitch until either our backup generator cuts in or I can turn the system off cleanly. We also have whole-house lightning and surge suppression units installed in the incoming electrical service plus another set on the incoming cable and phone lines. Trying what I can to keep a close lightning strike from entering the house... One in our backyard a few years ago did not do any damage to our stuff but took out the neighbor's TV and a few other things - his house is maybe 50 yards away and the strike was to a tree maybe 30' from our back deck.
 
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MtnHam

Industry Expert
Jan 12, 2014
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If you have a local Shunyata dealer, ask if you can demo in your system a Typhon QR. It is totally a passive device that removes all kinds of noise from the incoming power without any negative effects. I predict you will be shocked by the improvement in Sound Quality. Adding a Shunyata Triton v3 (distribution) will improve things even further.
 
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Folsom

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Note most components have power supplies that isolate the audio from the power line quite effectively. Unless the wall power is really bad chances are you would not notice any additional power filtering in a blind test. (Let the exceptions begin.)

Only in your dream world. There’s more to it.
 

twitch

Well-Known Member
Jun 17, 2010
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So how do I know if my system would benefit from
having any AC power correction (conditioner, isolation transformer, regenerator, etc.)

lick your finger and insert in receptacle ......... sorry I couldn't resist.

On a serious note I suspect you've gotten more than enough constructive responses so sit back and enjoy your music !
 

Chuck Lee

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Feb 5, 2015
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You never know what you have until it's gone...or so the saying goes.
In my experience everything sounds great, your ears tell you so.
Nothing sounds bad.
Only when you start to make changes will you know for sure if your power is as good as you think it is.
We can get used to the way our system sounds and just as some folks say our ears can trick us into believing we hear differences in power cords or fuses our ears can also trick us into thinking we have clean undistorted power and that everything is as good as it gets.
I've started at the panel and worked my way to my gear and each time I've made a change it's been audible.
Dedicated 20 amp lines, upgraded power receptacles and power cords and fuses have made some positive improvements in my system.
So have the different power conditioners that I've used and at the moment going to a balanced power conditioner and running it balanced at the panel( 110/110) has given me the best sound so far.
We spend lots of money on swapping gear in and out, like speakers and amps and sometimes we think we can cut corners and go cheap on things that some folks say shouldn't make any difference.
That's a mistake.
You will only get part of the performance your system is capable of if you choke it off with a cheap power cord as an example.
When you hear what a good power cord can do you'll know that you are on the right path.
But if you haven't done anything from the panel to your gear, you may never know that a power cord can make a difference.
I really believe that " I can't tell the difference" is because the system has been robbed of it's resolving powers because somewhere along the way, something was deemed unimportant in the overall big picture .
 

Chuck Lee

Well-Known Member
Feb 5, 2015
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Back in the old days power from the wall was pretty good.
Then I moved into a new just built modern home in an older subdivision.
I had Quads and Meitner mono amps about 1987.
One summer night the amps shut down so I shipped them off to Ed.
They came back and worked but a short time later they stopped again.
Ed said there must be something wrong at my end because the amps were going into protection mode.He said to have my power checked.
The hydro utility came down and were skeptical of my claims of 90 volts and less at the wall plug,maybe because I was using a Radio Shack device.
So they set up their device and came back after the weekend.
Their readings were the same as mine!
So what they did was replace an aging transformer up the street and all was well.
That transformer was in place way back before people had home A/C and pools and was under sized for modern times.
Everyone on that street benefitted from the upgrade not just me.
So wall pluggin became good enough and got the job done.
But my point is the power from the wall with the old transformer wasn't optimal yet no one had made any complaints about low power until I did- chalk one up for the audiophile.
How many other folks are in the same boat and don't know if their power is up to snuff?
The experience that got me into power conditioning was a few years later and I was using a Sunfire sub.
You know the one that used to dance across the floor.
Well there was something it did to my sound that I didn't like either.
The added bass was great for such a small unit, but the added noise not so much.
My electrician friend brought over a fluke and measured with the Sunfire in the system and when it was out of the system.
The graphs clearly showed that the Sunfire was adding all kinds of spikes and hash to the line, and my gear was sucking it up right out of the wall.
So I sold the sub and from what I learned about how all things on the line add noise I went over to the dark side and got into power conditioners.
Now 20 years later and things are even worse .
More stuff than ever to pollute our power from the wall.
To the folks who feel that wall pluggin is great then by all means have at it.
There was a time you could also take a drink right out of the river but I wouldn't try that today.
 

Gene 15352

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Feb 18, 2013
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I am currently experiencing a lot of noise on my ac line. Checked it with an Audio Prism Noise Sniffer. The sniffer doesn't display a read-out but you can definitely hear it through the machine. As a result, I'll be purchasing a line conditioner from either Audience, Shunyata, AQ Niagara or Torus as well as having an electrician check my grounding on the panel box. Here's my dilemma. I already have NCF a/c receptacles installed at the wall with NCF back plate, separate in-wall 10 awg Nomex wire cryogenically treated and JPS in-wall to the panel box for my amps, all on the same phase. My distribution box for my sources and pre-amp is of high quality with good copper wiring, NCF receptacles, star wiring etc. Was there even any advantage of going to all this trouble of separate dedicated ac lines, NCF receptacles if I'm still hearing noise? Very frustrating! The only positive thing I can think of is the 10 awg wire is good for lowering the resistance from my amps back to the panel. Should audiophiles subscribe to the blanket statement of "test the noise on your line and purchase a line conditioner if there' noise?" Thanks.
 

Folsom

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You have less noise than you would with shared lines. You could use some of my Lillies to lessen the effects of the noise that comes from other stuff in the house.
 

DonH50

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Jun 22, 2010
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Is the AC line noise actually coming out the speakers? Are you sure it is not some other noise source like motors or dimmers in the house coupling elsewhere into the system? I am a skeptic so no point in going further here...

It would be worth it to have the electrician check all the connections, however. I have many times found the screws in the service and on the outlets needed to be snugged down better some time after the initial installation. Things shift and move around a bit over time, wires can shift due to their own torsion (wrap) as well as from house shifts and such, and of course temperature changes can loosen things, so maybe all that's needed is to tighten things down again.

Assuming the power line noise is really making it to the speakers...

FWIWFM - Don
 

Folsom

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Your stereo is probably broken if you get anoise. Enoise modulates the signal, it isn’t perceivable as an artifact almost ever.
 

Gene 15352

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Feb 18, 2013
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Thank you for all your responses. No ground loop hum, very faint hiss through the speakers when volume is turned up. The utility room with electrical panel is only 10 feet away from the ac outlets. The noise is coming from both ac outlets being used in the system.
 

RogerD

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Thank you for all your responses. No ground loop hum, very faint hiss through the speakers when volume is turned up. The utility room with electrical panel is only 10 feet away from the ac outlets. The noise is coming from both ac outlets being used in the system.

So the noise is coming from the prism sniffer speaker, but you have a short dedicated run using 10AWG wire and your sockets are audiophile grade and installed by a electrician. No hum or hiss.....my conclusion....Throw the sniffer in the closet and forget about it....enjoy your music.
 
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Folsom

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Some amps have hiss no matter what. They're just slightly noisy in that way. BUT this does not mean they are bad amps or anything is wrong. Some of the most beloved amplifiers ever have had this, and people just never noticed because they couldn't care less. These amps would do it even battery powered, it's irrespective of AC quality on most amps.

Again, I highly suggest using some of my Lillies to help.
 

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