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AC mains noise Borrowed noise sniffer and tested my AC lines...

I borrowed this AC line noise sniffing device (Blue Horizon Mains Noise Analyser) today. (Do not ask from where, I do not feel at ease saying.)
This device sniffs out noise and has a range of "000" to "999" and over that it just is "MAX".
So first test was kitchen light with wall plug. "784"
Kitchen outlet tied to refrigerator (frig ON) "MAX"
Bedroom wall nothing around in use "220" wow good number.

Furutech Duplex at amplifier "013*" WHAT!!!! yes "013". That is on a direct 44 ft extension cord from 20 amp wall outlet (also Furutech) * with the C7 to the noise sniffer one way, it is 13, other way it is 20. ALL the measurements change with reversing the noise sniffer AC plug, about the same amount each time)
That extension does have an additional Furutech duplex on the cord, six feet back of amp Furutech plugs end, and that duplex has two PS Audio Noise Harvesters. The wiring is a quad twist. and each side or pair is connected to one out side. so each Noise Harvester is on one half of the quad.
So I can say the PS Audio Noise Harvesters really DO a fantastic job!!!

The other similar line (from he same 20 amp outlet) does not have any Noise Harvesters on it. And with the stereo running, it has "297" noise level. However IF I do stick one PS Audio Noise harvester in an out 3 feet back ot the one the sniffer is in. The noise drops to "143". (I cannot leave the Noise Harvester or a pair in there due to it being in use, normally, plus adding them in where the noise sniffer is, seems to make the sound go too thin.)

Another major discovery is just HOW NOISY Digital equipment really is!!! I have my two CD changers plugged into a separate power conditioner. A PS Audio P-600.
Testing the PS Audio P-600 I own (tested at 60Hz) With nothing turned on plugged into the P-600 the baseline noise is "040" With one five disc CD changer turned on the noise level jumps up to "740" With the other one only on the nose is also "740" with both on the noise jumps over "MAX" This is with a PS Audio Noise Harvester plugged into the same duplex (on the back of the P-600) as the CD changer!
On the other hand.. The Marantz SA-10 is pugged into the Furman (also with a PS Audio Noise Harvester in same duplex and that area is "032". So SOME equipment is not spewing, and some is.

This is all I have learned in a half hour of fooling around.
elizabeth
theo's avatar
theo
2,331 posts
 

Elizabeth, That is pretty extensive testing! I really appreciate your sharing the findings of your experiment. As mentioned I am looking at changing the direction in my own system on this matter. One thing that you mentioned is the common ground in circuits. That really re-enforces my thoughts on adding a dedicated ground stake for my 2 20 amp circuits so they won't share the same ground as the balance of the house.

I do think that Power Conditioning is something I want to continue in my system, but wonder if we over think it. Sometimes I get focused on one area of the system and obsess myself into spending money where it really isn't need. Maybe all I need is an afternoon of relaxation and vinyl...

erik_squires
5,268 posts
 
What’s different I think is the Alpha labs is specifically about EMI. It is limited to 10kHz to 10 MHz. This is also the range at which most cheap noise suppressors work. Kind of useless for audio gear IMHO. So, I am not at all surprised it has little bearing on sound quality.

We need to see everything between 60Hz to 20kHz. That is very little overlap with the Alpha Labs product. Sad because it’s much cheaper!

This is why the Furman gear is something I really like. Their noise suppression’s -6 dB point is at 3 kHz. A much more useful starting point.
ozzy's avatar
ozzy
3,650 posts
 
You can also try.
https://www.stetzerelectric.com/store/microsurge-meter/

They also sell the filters to reduce EMI

ozzy
elizabeth OP
6,726 posts
 
When I swapped the OEM Furman duplex to the Furutech duplex, I realized I need to keep the OEM noise suppressors added on the back of each OEM duplex. Glad I did swap them over.   
I am happy I was able to do the readings. No problem to report them So it they help anyone decide what direction to go in... great. 
The one thing I had not realized is how some audio equipment removes grunge from the line. And others. particularly the CD changers just SPEW tons of junk. I should measure the DVD players... ?? maybe.. And the plasma, just to know, while I have the tester in hand.                         
One device I decided not to buy because the reviews said the wall wart spewed tons of garbage in the line. Since it was a reclocker to 'fix' problems.. LOL why add another problem when you fix one!All in all I an happy about my power stuff.
erik_squires
5,268 posts
 
The one thing I had not realized is how some audio equipment removes grunge from the line. And others. particularly the CD changers just SPEW tons of junk. I should measure the DVD players... ?? maybe.. And the plasma, just to know, while I have the tester in hand.

Yep!!

This is why multiple filter banks (some Furman units have them) or keeping your digital (especially network) stuff outside your analog power conditioners can help lots.

I like to think of it as a kind of demilitarized zone (DMZ).

The inexpensive Furman with LiFT and SMP like this one:

https://amzn.to/2Gpffj3


for my wall warty stuff, and then something else for preamp and amps, like this:

https://amzn.to/2TqBJU9

This keeps my wall warts 2 entire filter sections away from my audio reproduction.


Unless you use an active device like a PS Audio regenerator, this type of isolation seems mandatory to me.

If you can't afford 2 units, at least keep your wall warts outside your conditioners.
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