[Ferbose]

I have briefly written about this before, when I reviewed Furman Power Factor Pro, but I guess not many people saw it.
Since the experience is truly interesting, I want to share it with more people.

In my lab there is a scientific instrument amplfier, costing about $4000. It was state of the art about 4-5 years ago, and it is used to measure pA currents from single neurons.

Just how sensitive is this amplifier?

Suppose you have thinnest copper wire imaginable, made of a sigle file of copper atoms (such wire does not exist). Take 1 meter of this ultra-thin wire and attach it to a 1.5V battery, the current you get is about 1 pA.

Another way to think about it. When a 10 cm wire is attached to the amplifier, it can detect the electromagnetic field generated by a person walking by, even when the wire is placed inside a five-side shielded Faraday cage. The cage is sitting on an air-stabilized steel table, with four shielding meshes on three sides and the top. Only one side is left as an opening so the experimenter can perform the work. Despite all this shielding, it can still detect the EM wave generated by a moving person. This is different from your body's interference with the indoor TV antenna. At home, a person is simply blocking an outside broadcast. In the lab, there is no EM broadcast. Instead, a walking person becomes the EM wave broadcast station.

As you can imagine, such super-sensitive amplifiers must have a superb power supply. In fact, you can't build an amplifier much more sensitive than this. Still, the amplifier has some internal noise.

One day we were just wondering if we can lower the noise floor of the amplifier. Normally, the amp is plugged into a cheap power strip. This is when I took my $229 Furman Power Factor Pro to the lab and plugged it in. To our delight, the amp's self-noise decreased about 30%, as seen on the oscilloscope. Wow, we can SEE this thing really works!

As you can read in my review, everything I have plugged into Power Factor Pro sounds better, especially components with seemingly weak power supplies. Seeing that it can lower the noise of even one of the world's most sensitive instrument amplifiers, I am completely sold on this unit. It is no coincidence that Furman is a leader of power conditioning products for the pro audio market. Even their cheaper stuff REALLY works. It certainly brought some improvement to a hi-end, ultra-sensitive scientific amplifier. If your home audio components are not as precision-made as some of the world's most sensitive scientific amplifiers, I am pretty sure Power Factor Pro will also serve you well.

 

[gevorg]

Thanks for sharing your finding, very interesting.

Its no doubt that power conditioning makes a difference, the question is how audible it is, and if it is the best upgrade in a particular system.

 

[JahJahBinks]

very interesting finding, thanks.

 

[shplorgh]

Cool, good job!

But the "objectivists" will still find ways to blatantly ignore scientific proof.

 

[felixkrull6]

Ferbose,

First off, great review. I like the fact that you actually added some science to your review.

My only reservation is that I have to use an extension cord before I reach the point where I can use a power conditioner to plug in the rest of my gear. How do you think this will affect the conditioning? I don't think it will matter but I really don't know.

 

[clarke68]

Quote:

Originally Posted by hungrych But the "objectivists" will still find ways to blatantly ignore scientific proof.

I doubt these stick-in-the-mud "objectivists" would ignore scientific proof, but they may ask, "proof of what?"

Ferbose has demonstrated that the unit successfully reduces AC noise, which shows that Furman's engineers know what they're doing. However, marketing materials for the Power Factor Pro claim that the unit will "vastly improve your instrument amplifier's tone and clarity".

What will it do?

"Improve your amplifier's tone!"

How much?

"Vastly!"

These are subjective statements that can't be proven by an oscilloscope. Lots of things can be done to improve signal quality, but many of them don't affect any frequencies within the audio band.

I'm not saying the Furman unit is one of these, and I'm not saying it doesn't improve the sound of audio systems...how would I know? I've never even seen one, let alone heard one. Ferbose likes it and he's got ears. All I'm saying is be careful where you point that "scientific proof".

Ferbose: All that said, I really appreciate the efforts you put forth to test the unit...that kind of stuff makes Head-Fi a valuable asset to the audio enthusiast community. If I ever discover a need for power conditioning, I'll probably look no further than the Power Factor Pro.

 

[Solude]

I personally like power conditioners, see my sig... but not all conditioners are created equal and a lot of them fix things that aren't likely to be present in the first place

http://www.hometheaterhifi.com/volum...et-4-2002.html

This is a review of the PS Audio UO and to say it did nothing on the scope would be a large understatement. The PS fixes things that obviously weren't present at the reviewer's lab. So although the Furman worked great in that lab, that's not say it wouldn't be useless elsewhere.

Again, I have a beast of a power rig, the trifecta conditioning, regeneration and surge protection. But without the scope I might just have a really big surge protector

 

[edstrelow]

Quote:

Originally Posted by clarke68 I doubt these stick-in-the-mud "objectivists" would ignore scientific proof, but they may ask, "proof of what?" Ferbose has demonstrated that the unit successfully reduces AC noise, which shows that Furman's engineers know what they're doing. However, marketing materials for the Power Factor Pro claim that the unit will "vastly improve your instrument amplifier's tone and clarity". What will it do? "Improve your amplifier's tone!" How much? "Vastly!"

Showing a difference on an oscilloscope or by other measurement is at least a start to showing that a tweak is actually doing something.

Good psychphysical testing to assess how perceptible or meaningful such differences are is much more difficult than your average tweak sceptic realizes. For example it is easy to show no difference between two conditions if an experiment is badly set up, has poor equipment, subjects are not trained or whatever. In science, little stock is given to null results partly for these reasons.

I take the position that the human ear is incredibly sensitive and that a trained listener (including a golden ear) is likely to be able to detect, if only at a very low level of awareness, of many if not most things that can be measured in sound signals.

 

[JahJahBinks]

also how much coffee he had in the morning, too many variables to consider.

 

[terrymx]

Quote:

Originally Posted by felixkrull6 Ferbose, First off, great review. I like the fact that you actually added some science to your review. My only reservation is that I have to use an extension cord before I reach the point where I can use a power conditioner to plug in the rest of my gear. How do you think this will affect the conditioning? I don't think it will matter but I really don't know.

seconded. say you use the power conditioner to your amps, but you use a regular cord for the power conditioner to the wall or regular cord from your p.c. to your amp. do you loose that special shielding and stuff.

 

[slwiser]

How would the Tipplight Omni1000LCD UPS for $99 at Costco compare with these units?

 

[NotJeffBuckley]

Quote:

Originally Posted by edstrelow I take the position that the human ear is incredibly sensitive and that a trained listener (including a golden ear) is likely to be able to detect, if only at a very low level of awareness, of many if not most things that can be measured in sound signals.

I agree that the human ear/human brain system is capable of detecting subtleties, and that if something is significantly measurably different about the signal it's probable that the change is perceptible. My previous crusade against subjectvism on this board was aimed at the need to spend megabucks to get certain changes, not at tweaks in general. Objectivists aren't as one-dimensional as that guy seems to think

 

[bigshot]

I scanned through this thread and I didn't see any mention of the signal to noise rating on the amp with and without the conditioner. What is it? The noise decreased 30% of what?

It's good that it does something, but without knowing how much it does... what can you say?

See ya
Steve

 

[stryker]

Anyone have any experience with this "power conditioner"? Yes, it's a cable, but it's really a power conditioner within a cable.

http://www.sacdmods.com/SAPC-1.htm

 

[Ferbose]

Quote:

Originally Posted by bigshot I scanned through this thread and I didn't see any mention of the signal to noise rating on the amp with and without the conditioner. What is it? The noise decreased 30% of what? It's good that it does something, but without knowing how much it does... what can you say? See ya Steve

All amplifiers have internal noise floor. You see the noise trace on the oscilloscope, and the up and downs got smaller after using the conditioner. If the internal noise is between -10 to 10 microvolts (arbitrary unit), now it looks like -7 to 7 microvolts.
Regardless of S/N ratio, if you lower noise floor by 30%, you increase S/N by 3 dB.
I actually went into the datasheet of the instrument amplifier and calculated its S/N to be 107 dB. Of course, this amplifier has a very special purpose (voltage clamping), which is very different from audio amplifiers, so directly comparing S/N numbers is not meaningful.
The point is, this is a state-of-the-art scientific equipment in its class a few years ago for extremely sensitive measurements. We can trust that it has an excellent power supply. The fact that it still benefits from a power conditioner is pretty remarkable, and convinces me that power conditioning benefits I heard are not just imaginations.