Seems to me the DeZorel is suceptible to inductive effects and each component must be plugged separately, or if need be, by means of a wired in parallel power strip. I have not read anything about this anywhere, but it is my suspicion. Perhaps Dejan or Miki can answer the question for us...
My own findings (and you'll have to ask Miki for his/theirs) are quite to the contrary, that it is very insensitive to inductive loading. This is based on about 3 months of intensively researching it a year and a half ago, when I was preparing that piece for TNT.
But I did find something else - with some power supplies, not even that filter helps much. What I mean is this - if a power supply is well made, using quality components and in proper size to its purpose, the filter will help anything from good to outstanding. Conversly, if the power supply has a poor quality power transformer, and/or filter caps not up to the job (which, bear in mind, may also mean that they are overdue for a change because they have dried up over a certain point), the filter will not make much of a difference in overall definition and clarity, just in noise and absolute power delivery.
I saw this happen with gear ranging from very cheap to darn expensive. New Technics and Sony models profited much, but older units (older being 5+ years of age) much less. The same was true for my own Yamaha AX 592, which was heading for a cap change anyway. Immediately after changing the caps by installing identical model new ones, the difference turned drastic on me, for the better. I repeated this experience on my older Harman/Kardon 6550, also slated for cap change after 8 years of faithful service; again, immediately after the cap change, the difference was obvious and not at all small.
The third sample was a friend's Denon integrated amp, as I was asked to change the caps for him. I took the opportunity to check out this effect with that too, and sure enough, it was there.
Moving on to somewhat higher priced gear, a Krell integrated showed improvements, but not much so - quite the opposite with a power amp of theirs, costing like 3 times that integrated. Comparing their power supplies showed meagre dimensioning for the integrated (hey, a 400 VA transformer for 2x150W? Gimme a break!), but very substantial for the power amp.
The last straw was a Cyrus integrated as is, where improvements were there but hardly stunning, and that same amp with their add-on power supply, where the differences were almost stunning - literally.
It all brings me back to what I keep saying - no line filter can improve your audio, all it can do is free it to perform as best as it can, but ultimately, your audio will determine what you hear.
Why did Jerry hear a substantial difference? No brainer, Audio Research has outstanding quality and size of power supplies, always did, one of their hallmarks. Why do I hear it so clearly? Because my Harman/Kardon 680 has a very good, true dual mono power supply, and my Karan Acoustics KA-i180 also has a well designed power supply.
Anyone following the thread on amplifiers will see my very numerous references to power supplies - they can kill a model dead straight out if not done properly, and just dumping a lot of fancy capacitors inside does not make those supplies well made - just expensive.
I am sorry Dan Banquer is not in on this, because his amps use fully regulated power supplies - now there, I would expect the results to be outstanding, Dan does not skimp on the juice (fact is, he's almost as mad about them as I am, and I admit to being a freak).
I would also add one last comment - I wondered for a while why does that filter make such obvious differences with tube audio and much more unpredictable differences with solid state, until I realized a simple fact. Tube audio usually has better power supplies than solid state; note the word "usually". I checked this by using the filter on solid state products known to have very good power supplies (e.g. Naim, Mark Levinson, etc) and sure enough, I got marked differences, not at all hard to hear.
Just my thoughts.
Cheers,
DVV
