September 21, 2009

Absolute Power Corrupts! Audio Prism Noise Sniffer.

Audio Prism Noise Sniffer sniffs out all the EMI/RFI noise riding along the power lines to your hifi system.

To some I seemed to be obsessed with power! Power supply for our precious hifi system, that is. Well, let's just say that it all started with a quest for lower noise floor for my audio system, and somehow, for every question I managed to find an answer to, more new questions sprouts in to my curious mind.

Along the way, came the Audio Prism Noise Sniffer, courtesy of Kenny of Hi-Way Laser, which retails at RM$895.00 each. As it's name indicates, the device sniffs out the dreadful EMI/RFI noise from your power points, which supplies the all important A/C juice to your hifi system. Now you can't fight an enemy that you can't see or hear. The simple looking Audio Prism Noise Sniffer, once plugged in to the power point, allows you to hear how dirty, nasty EMI/RFI sounds, via a little speaker and a volume(more of a sensitivity) knob. The manual advises to turn the volume(sensitivity) knob to 12'o clock to check for noise once plugged in to a power point. If you can't hear anything, then try to further turn up volume knob and see if you hear any further disturbing noise. Real easy!

I was curious how loud the EMI/RFI noise on the power would be, so I borrowed an SPL meter froma friend to make things just a little more informative.

When I first plugged in to the power point used to power my whole hifi system, turned the volume knob to 12'o clock as per suggested by the manual, I heard a very rude loud noise via the built in speaker of the Noise Sniffer device. I was shocked! But I was also curious, how loud is the noise? I asked around some sifus, and came to this conclusion.

That's how the noise is measured, just to give you an idea.

I first need to know my room ambient noise floor as a base line reference. Then I need to know how loud the EMI/RFI noise is from the power outlet. I borrowed an analog SPL meter from a friend and bingo! I can now measure everything in db scale. I merely placed the SPL meter pick up mic at the middle of the built in speaker of the Noise Sniffer each time I want to measure something. Oh, just one more thing, I made sure every equipment in the hifi chain is switched "on" to simulate the real world use of an hifi system.

Audio Prism Quiet Line MKIII Parallel A/C Line Filter plug.

I first measure my room's noise floor, which shows 52db. I proceeded to measure again the power point used to power ny hifi system. No wonder I had a very rude shock, the decibel meter swung wildly pointing to 112dbs! I then proceed to check how effective my Torus Power RM8A PLC is, by plugging the Noise Sniffer in to one of the spare outlets. This time, I was in for another pleasant suprise! The decibel meter only indicated 54db of a very soft "be....ep, be......ep" sound. WOW! The Torus Power really works! It has managed to bring EMI/RFI noise levels down by a whooping 58dbs, just 2dbs above room's ambient! Highly impressive indeed, however when Odiosleuth threw me one of his spare Audio Prism Quiet Line MKIII parallel A/C line filter (BS std)plug, just nice for plugging in to one of the Torus Power RM8A's spare outlets, I proceeded to measure the noise again, but only this time, the last 2dbs of "be...ep, b....eep" transformer residue noise also turned silent! This is truly brilliant stuff.

The Audio Prism Quiet Line MK parallel A/C line filter plug, installed at the end of the spare outlets on the back of the Torus Power RM8A. Silenced the 2db transformer residue noise.

I then wondered what will happen if I plugged the Noise Sniffer in to my Wireworld Electrifier distributor powered by a 10ft long JPS Inwall power cable. With all my hifi equipment switched on as before, I proceeded with the same test, and again, I am surprised by my findings, the EMI/RFI readings this time shows 71dbs on the Wireworld distributor! That means the 10ft long JPS Inwall was acting like an EMI/RFI antenna, picking up 17dbs of noise along the way!

I know, I know, some of you readers have previously pointed this issue out to me, and are now thinking smugly "I told you so!". I can now confirm that you guys were correct to raise concern of the issue. Please give your self a big pat on the back! Lesson learnt for me.

Isotek Isoplug though the circuit design is very slightly diferent from the Audio Prism product above, but just as effective in soaking up EMI/RFI noise from the power lines.

Now that I know my problems I set out to fix it. I went to the friendly Center Circle Audio guys to borrow an Isotek Isoplug, and an Isotek Multiway distributor. I plug the Isoplug in to one of the spare outlets on the Wireworld Electrifier, and this time, I can confirmed my suspicions. The speaker of the Noise Sniffer was silent, I turn the volume further up till full, it remained dead silent! The Isoplug was absolutely effective, that it brought down all the 19dbs of noise picked up by the long power cable including the remaining 2dbs of transformer residue noise from the Torus Power PLC.

The Isotek Multiway only has minimal noise filtering capabilities, but does provide surge protection for hifi equipment plugged in to it.

The Isotek Multiway was less effective as it was only a very mild filter plus surge protection model. I swap the entire Wireworld Electrifier over to the Isotek Multiway, sans the Isoplug and the measured noise levels went back up to 69dbs! only 2dbs better than the Wireworld Electrifier. I plugged in the Isoplug back in to the Isotek Multiway, and all those RFI/EMI noise went away again, just eerily quiet like as earlier experienced.

Of the two possible solutions, the Wireworld Electrifier and Isoplug combo proved superior in total EMI/RFI noise elimination.

I reverted to the Wireworld Electrifier and Isoplug combo, which I found so effective, and started listening to some music. It's good to know that sometimes, technical results does co-relate to what one hears in music reproduction.

My final choice, the Isoplug does run hot to touch, as it converts noise to heat.

I heard more silent, jet black back ground noise, if any at all, with volume at pre amp adjusted to my usual listening levels. When the music played, the first thing that struck me was how much more relieved all the vocal and instrument images are from the black back ground of the sound stage. I heard better low level resolution, inner micro details within the music mix. I also heard sharper transient response, and some improvements in musical dynamics. All in small quantities, you might say, but it all certainly adds up to better musical enjoyment and fatigue free listening. I could feel much more "connected" to the musical playback easily compared to before.

The most effective and useful hifi tool I've come across so far, price at RM$895.00 each, every high end aspiring audiophile, and those serious about noise floor reduction/elimination, should have one!

I've never come across a more useful audio tool before the Audio Prism Noise Sniffer! I am considering very hard on purchasing the review sample. However, I bought Odiosleuth's spare Audio Prism Quiet Line MKIII and the Isotek Isoplug to fix my noise issue.

Stick around, as I use the Noise Sniffer to check out the most effective PLCs, power cords, Klang Valley power supply noise and confirm or perhaps,reject a few power related speculations and myths too!


Audio Prism power products sold by Hi-Way Laser, contact Kenny Sin, tel:019-2813399

Isotek Power System products sold by Center Circle Audio, contact Sky, tel:03-77282686

1 comment:

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