2. misc-audio
  3. 145462-1445

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
erik_squires
5,268 posts
 
This is pretty awesome. Too expensive for me to play with, but I have wanted something short of an AC noise analyzer that was easy to use for a long time.

I have used oscilloscopes to examine problems from wall warts, and digital power supplies before, and I know from experience the Furman unit I have really makes my stereo sound better.

One really interesting thing from this article is the quality of noise coming out of the Hypex units. I totally believe it. When I build I add ferrite cores to the AC lines, but I have no idea if they really help.

Would be really interesting if the problems with Class D amps was not the amp, but the noise they inject.

Then the problem is not about what gear they match, but how good the power supplies in the other gear is.
erik_squires
5,268 posts
 
But system on. Second measurement twenty minutes later was "003" (I am thunderstruck.) Music was playing.        


I am sorry, but what does this mean?  What changed?

theo's avatar
theo
2,331 posts
 
Interesting indeed. I have been looking at different AC conditioners and power distribution strips, e.g. Shunyata, synergistic Research, Cardas, etc. My thought is to replace my 2) Running Springs units to save space. I have looked for a Noise Sniffer as Elizabeth has been fortunate enough to obtain. 
Obviously too expensive to own for a one time purchase. It would be nice if Audio stores or manufacturers would offer rental on such devices to help sell their products.
That aside, I have a question for Elizabeth, not knowing how long you have possession of this device, but if you could let us know how the readings vary at different times of the day. And when you get a low reading on one component do you plan to test one of the higher reading components as close to the same time? It could reveal just how much the electricity coming into the house fluctuates thru the day.





elizabeth OP
6,726 posts
 
Use of the device while place is closed. Late Saturday until early Tuesday only.     
I am not going to bother test all day.. It IS Sunday. Only possible change might be on Monday.. But not much here. I might if I fel like it. But no way comprehensive checking.           
As for 'making the sound bad with PS Audio Noise Sniffers'. Yes, the can, location IS important. And the usual problem of lean sound due to too much filtering is well known to me. Any of the various filtering devices, overdone, can damage the sound. Mainly by making it thinner, tighter, leaner bass,.. You name it.      
The question: "What does it mean" Philosophical?? I guess what it means is the noise was lower at taht outlet at that time, curiously while music was being played.when music was being played. Period.If you cannot live without knowing why, you are SOL here.      
This Morning I an unplugging everything to get a baseline of the actual wall I take the AC from, and each stage asI plug stuff back in. Also searching for the 'worst offenders' injecting garbage back in. (Like the Laptop charger, known bad. And where the AM music is being injected on the separate Adcom power conditioner used for the cable and WiFi etc. Adcom may be moved off stereo AC? if it is not stopping this stuff.
kodak805
44 posts
 
For a less expensive alternative you might try this Power line Meter direct from AlphaLab:

https://www.alphalabinc.com/product/plm/

I sold my expensive Akiko Corelli Passive Conditioner when I found it actually increased lpower line noise.

I hope this helps!


More to discover