I am an avid reader of Audiogon and the Audio Asylum, but rarely contribute due to my status as a distributor; however, I believe that I can offer some considered thoughts to this thread and add a fresh perspective without (appearing to be) flogging any of the products I represent.
I think it is important to state that I was at one time firmly in 'the best power conditioner is no power conditioner' camp.
I am also of the philosophy that if a system or component is not musically satisfying, then it has failed in its ultimate goal: communication of the music. I also use this as my primary criteria in evaluation of any component, cable and accessory changes in my system. If the new element in my system does not allow me to better connect with the music, it doesn't matter what other sonic attributes it has*.
Also let me disclose up front that I am the principle for a company called Music First Distribution. We are the US Distributor for Foundation Research Audio Electronics, the line currently offers a line level preamp, a phono stage and a series of components designated as the 'Noise Reduction System'.
It would be easy for one to conclude that I am now a 'believer' because I sell noise reduction components, but actually, I sell these components because they are what finally convinced me that effective noise reduction is an absolute requirement.
In my experience, systems assembled around effective noise reduction are often able to transcend both the medium and the equipment. When properly assembled and voiced, these systems allow the listener to get closer to the music by conveying the ultimate in musically significant resolution and low level detail, without the accompanying amusical artifacts due to external noise.
In my opinion and again based on my experience, a well designed and EFFECTIVE noise reduction component must:
1) First and above all, do no harm:
The noise reduction component must add no sonic signature or coloration of its own. For A/C line conditioners, a critical aspect of this requirement, and the downfall of the majority of in-line conditioner designs is the requirement that the conditioner MUST NOT be the current limiting element in the specific application or circuit. I strongly believe that current limiting is one of the largest flaws in A/C line conditioner design. Underpowered A/C regenerating devices, power bars and other distributed conditioning solutions are anathema to the above dictum, and those of us** who have spent the time and money to dedicate high current power delivery to individual components naturally (and correctly) shy away from these designs.
2) Offer effective noise reduction:
In my experience, bi-directional noise reduction is the most effective noise reduction method, i.e. not only isolating the component from the power grid, but also, and often more importantly, isolating the component from the rest of the system. Bi-directional filtration is especially important on digital components and class D amplifier designs, which can inject high frequency noise back into the rest of the system. It therefore follows from dictum 2) that, A/C line conditioners must also:
3) Be dedicated to individual components:
In my opinion, this is the only way that true isolation between components can be achieved.
It is my experience that when well designed noise reduction components meeting the above three criteria are installed on the vast majority of systems, the improvements are not only dramatic and without drawbacks, but also revolutionary. In the past, I was always one who viewed the words 'neutral' 'detailed' and 'revealing' as negative attributes that were contrary to the objective of musicality. I now believe that this view was mainly due to the fact that truly neutral components do nothing to mask the noise present in the system. Quite often, components and systems that are branded 'hi-fi' or 'audiophile' in the perjurative sense, are transformed with the application of effective noise reduction so the first thing that impresses the listener is the musical "rightness" of the system.
Well designed noise reduction components (lets call them WDNRCs) do two things in the above type of application:
a) First, WDNRCs dramatically lower the noise floor revealing tremendous amounts of true, subtle, low level musical detail. This detail that was previously masked has a tremendous impact on the ability of the listener to connect with the music.
b) Secondly, WDNRCs remove the A/C RFI and EMI noise that is ubiquitous in every system to various degrees. These noise artifacts have the effect of artificially highlighting frequencies where the noise manifests itself. Also, the noise artifacts are amusical and instead of these frequencies adding to the musical experience, they cause listening fatigue and unnatural listener tension that ultimately reduces and more often eliminates the ability of the listener to connect with the music. Classic manifestations of this type of noise are unnatural vocal sibilance not present in the original recording and distortions on crash cymbals and high hats in drum kits (for me high hats are the most difficult test to pass). The presence of external A/C RFI and EMI noise causes these sibilances and cymbals to separate from the musical tapestry and they appear to separate from the soundstage. They are so easy to pick out once the phenomena is pointed out that even casual listeners can pick them out with ease. Because these distortions are errors of commission, where the noise floor effect discussed in a) above is an error of omission, they are, for me, the greatest reason that a system fails to communicate the musical message***.
So why is there a large faction of audiophiles and music lovers who swear at noise reduction products instead of swearing by them?
I) The main reason is that there are very, very few products that meet the above three criteria. Most power conditioners fail because they do not pass dictum 1, sometimes by choice but more often due to poor design.
II) Also, there are rare occasions where even effective noise reduction does not appear to be beneficial, and here's why.
There are those audiophiles/music lovers who have voiced their system so as to reduce the artifacts of A/C (and RFI and EMI) noise**** and have done so in the absence of WDNRCs. These systems are usually developed over long periods of time by audiophiles/music lovers with educated ears and with the necessary time and resources. It is important to realize, however, that the only way to reduce the artifacts of noise described in b) above by methods other than the utilization of WDNRCs is by tailoring the frequency response of the system to reduce or 'omit' the noise at the offending frequencies. Unfortunately this method always comes at the expense of masking true musical information in the frequencies where the offending noise resides. The installation of even the best power conditioners in these systems almost always results in a perceived loss of life and detail. More often than not the noise reduction component is removed as the offending element when other system components are ultimately responsible.
Systems such as these are the result of errors of omission. The irony is that systems developed in this way are always more satisfying musically than those that are ruthlessly revealing, but they are no more correct, and while they are not offensive they ultimately do a disservice to the musical message by masking musically significant (essential) detail.
So what does one do? First don't give up on noise reduction! Search out noise reduction products that meet the above criteria. Read David Magnan's treatise on tweaks at http://www.magnan.com/column.shtml. Have fun, keep an open mind and re-explore noise reduction products. Dont be afraid of re-evaluating your system components if you find yourself in the pleasantly musical camp and noise reduction appears to rob your system. It may be a case of taking one step back to take 10 steps forward. I know it was for me.
Lastly, don't take my word for anything! Challenge my perspective by experimentation and post your findings. I gave up taking strangers' (goners', reviewers', manufacturers', distributors', dealers', audio gurus' etc.) opinions at face value about 10 years ago. My system has thanked me for it ever since.
And always remember the best thing one can spend on one's system is time.
Kerry Legeard B. A. Sc. P. Eng
Music First Distribution
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*There are pitfalls to using this methodology as I describe in item II) towards the end of of my post.
**My personal dedicated listening room, and one of our three beta test sites is equipped with a top of the line General Electric industrial 225 amp panel box with a super duty silver plated copper bus and bolt on low noise silver contact breakers. This panel box delivers power to 10 dedicated 20 amp circuits isolated on the quietest leg of the utility power transformer via solid core 10 gauge OFC wiring.+ WDNRCs sized appropriately for the components not only work well in this type of setup, they are indispensable and have no downside!
+(I also have the ability to switch each line between 120 and 240 volts if the component can be configured to accept 240 volts. The impact of 240 versus 120 volt A/C configuration is substantial and requires another, much longer discussion.)
***Not coincidentally, many of the areas discussed here are where digital has, and continues (albeit to a lesser degree) to fail. It is my opininon that many (but not all) of the problems thought to be inherent to the technology are due to RF noise generated by poorly isolated digital circuitry which not only contaminates the analog sections of the DAC but also the A/C to the rest of the system.
****Some individual components and even entire lines of components are 'voiced' so as to reduce offending external noise elements.
