Silver Circle Audio pure power one 5.0
A great unit gets upgraded!
Review By Rick Jensen
here to e-mail reviewer.
am increasingly convinced that noise, artificial noise of all sorts, is
among the principal elements that prevent the reproduced sound experience
in the home from sounding like something live. It's almost too easy,
albeit probably true, merely to invoke the maxim that nothing can and will
sound like live music in a real space. I guess I agree with that; there is
nothing that seems to indicate that it is not so.
Within that familiar statement are a host
of factors that are potentially responsible --the size of a real concert
space, the period and propagation of sound waves as well as the physical
nature of their sources, the lack of mistakes by performers and coughs
from the audience. We can all come up with our lists.
But the spurious sounds, however subtle,
that make their way into the reproduction of a recording, seem to me to be
of a different nature. They impose themselves on the musical performance
in a ‘global' way – i. e. across the spectrum of the music that we
hear. Depending on the source, they may be inherently or largely amusical
– hums, white noise, intermittent distortions, shadows or reflections of
other signals in the chain, and more. There may be noises and distractions
in the concert hall. One hears horns, police sirens, traffic, ventilation
systems, and the rustling of papers. These things may also be "amusical".
But an important difference is that they are transitory, and do not
normally become part of the musical performance; they don't accompany you
throughout the evening. I believe what I am indicating is that that is a
big advantage in favor of the concert hall.
All of which brings me (again) to the
subject of this review update – the
pure power one 5.0 power conditioner. Or as I am fond of telling any
non-audiophile who sees it, a really big, heavy, expensive power strip. If
you are reading this, of course, you know it is much more.
I will recap only briefly the conditions prior
to my review of the original version. I had had some serious noise
problems in my system (really, in my house) several years ago. It became
enough of a problem that I first ceased to use my system for a few months
while I was unable to fix it. I had a separate and dedicated line to the
stereo room from our electrical panel installed, along with high-grade
receptacles for the room. Yes, we could have tried to have the line go
back to the utility line in the street, but that would have required
permits from the town fathers, which are not easily forthcoming.
I did try a number of other filters and
conditioners from some well-respected manufacturers, but couldn't fix the
problem completely. Then I heard (really, I saw) the
pure power one 5.0 (PP1 from here on in) at a show in 2007 where I met
Dave Stanard, the head of
.The system in which it was playing sounded sensational. I inquired about
the PP1, and thought it might have something to do with the fine sound.
Dave sent me a unit for review, and my noise problems were solved. I
won't repeat here all the details about the design of the unit, about the
goals, or about the construction. You can refer to my
original review of the Silver Circle Audio pure power one 5.0.To
be brief, the PP1 is pretty massive for anything that is not an amplifier.
It looks about the size of a large amplifier and weighs 110 lbs.It is not
easy to carry around the house, but presumably that would not be your goal
in owning one.And, as I mentioned earlier, it comes with the high-end
Vesuvius power cord made by
(of which there is a new model – see below), which is beautifully built
and happily, somewhat more flexible than tempered steel.
So, why the update? What has changed? Just two
things – the filter and the cord.However, the major change involves the
filter. As I listened to the new unit with an updated version of the
original power cord, but not with the optional Vesuvius dcβ, my
comments will need to be taken in that light. Accord
to Dave Stanard, the original filter was a hand made version of a very
common circuit used to filter out common mode and differential mode noise.
After living a long time with his original creation and extended
listening, Stanard figured they could do better and began experimenting
with various filters. As noted in my original review,
products are not the reflection of a specific design methodology, other
than trial and error through both measurement and lots of listening.
Based on the recommendations of various
engineers and audio designers,
arrived at using a filter that is a combination of resistive and
capacitive elements. They are not ready to publish the schematic, but the
new filter far outperformed the old with respect to the job it had to do.
, the huge isolation transformer removes about 99.99% of the common mode
noise found in the line. The filter removes the rest of the common noise
as well as the differential mode noise, and the new filter just did a
noticeably better job.
With regard to the new Vesuvius power cord,
as I did not audition it, I will just repeat what
describes. They found that when DC is present on an AC line in excess of 1
volt, it makes a torroidal hum. They designed a Vesuvius power cord (the
Vesuvius dcβ - $950 separately) that removes the DC with an inline
diode/capacitor circuit. Stanard notes on his website "what is even more
interesting is that in listening tests, we found that the inclusion of
this circuit actually increased dynamic "slam" and detail in the music. I
believe it's a result of the theory of unintended consequences, or the
travels of the Three Princes of Serendip. This is not what we were looking
for, but we'll take it. Reducing DC and increasing dynamics."
So, how did it sound, or not sound, as the
case may be? I would probably not be writing this if it were not worth the
First, the whole system is quieter than
ever, which, after all, has to be the main objective. I have to get right
up next to the speakers to hear any kind of noise, and that with the
volume turned up a level that most would consider quite loud. That aside,
there is just an overall sense of quiet. With digital sources it's
actually a little eerie. I realize now that I have always known when the
system is on (of course, the glow from the tubes gives it away) by ear –
so when the music starts it's a surprise but not a shock. With the new
PP1, it comes out of nowhere and gives me a start most of the time.
fact, with the Empire Brass Quintet's first cut ("Hopper Dance") on the McLaren
Test Tracks CD (available used from Amazon), I jumped every time. This
test CD has some very well-recorded tracks and some of them, like this
percussive piece, are very enjoyable as well – not always the case on
demo discs. What also struck me here is that the brass had the attack that
one would look for but not the aggressive leading edge, that kind of
bleat, that one often hears with recorded music. There was a certain
softness to the horn tones that reminded me of live music, where brass
sections can be exciting without frying your eardrums. The drums – the
other stars of this cut, are deep and round with great depth and
definition. And the dynamics are all one could wish for; I have played
this recording for friends, all of whom have wanted to get their own copy
As a contrasting piece on the same disc,
there is a Sara K recording of "Brick House". While it isn't my favorite
music, it is well-recorded with good ambience. Her voice is intimate and a
little smoky and lacks no detail. The string bass at the beginning, like
the earlier cut, has great detail even while being soft, like a real (not
"Home" from New York Reunion by the
McCoy Tyner Quartet [Chesky SACD 206] is one of my favorite cuts, and one
I listen to with every piece of equipment for a sense of continuity and comparison. Until
hearing this via the new PP1, I had not noticed the extent to which the
Ron Carter – Tyner interplay is what drives this song. It's a great
melody, but I got the impression that if the song is "about" something, it
may well be changes in rhythm (come up with whatever metaphor you want to
fit the title as well). My listening notes said "no haze at all" – maybe
that allowed me to hear through it better.
The same sense of naturalness pervaded the
Mozart Clarinet Concerto from Antony Michaelson / Michaelangelo Chamber
Orchestra [MFSACD017].This is a very well recorded and nicely played SACD.
The spaces both linear (between the notes) and spatial (soundstage) gave
the feel of live music – it was just stress-free. Given that my
listening room is a small one, there is always a danger that the smaller
space will render certain instruments or certain passages too aggressive
compared to live.
In that context, "stress-free" is a good thing. As above, I believe that
the delicacy, richness and natural dynamics that I kept noticing were a
result of the absence of non-musical signals.
Conclusion / Reflection
Having had the good fortune to hear a lot of
very fine audio equipment over the years, I have had many occasions where
I have been surprised by something good that I had never heard before. Most
of us have had these "aha" moments. In the earlier review, I noted that
only the Grand Prix Audio Monaco equipment stand shocked me anywhere near
as did the PP1.One other component that dropped my jaw in the same fashion
was my original Linn turntable, almost thirty years ago. I was given one
of those demonstrations where the arm, cartridge and cabling were all
identical, but the turntable was different (in this case, it was the old
CJ Walker). The Linn trounced the
, and I had no idea why or how. One reacts in much the same way to the PP1
.A line conditioner? An equipment stand? They don't even make music.
While my experience may not parallel that
of others, I might hazard a guess at why these three stand out. All three
are more or less passive components. They are not passing the signal. All
they really have to do is to get out of the way and/or to help other
components to get out of the way. By being silent, whether via attenuation
of vibration (GP Audio and Linn) or cleaning up the power line (
), they strip away the haze and the garbage that can affect every part of
the music, every bit of the reproduced recording. Perhaps it is not such a
surprise that the improvements in the listening experience from components
such as these can be dramatic, because their impact is potentially so broad. I
don't know for sure; as I said, this is a guess.
Regardless of why the PP1 manages to make
everything else sound so good, what remains is that it does. There are
likely other power conditioners out there that do a similarly great job. I
have not had the chance to hear them all, and certainly not under
‘controlled' conditions. But the PP1 merits the serious consideration of
anyone who has an investment in a music system – hardware and software
– and anyone who is invested in music. It
remains a great and essential component and while the price remains
at $5000, existing owners can have their units upgraded by Silver Circle
by paying the shipping costs to and from the factory.
Type: Power filtration and distribution unit
5.0 kVa Proprietary 75 pound isolation transformer
Massive black anodized aluminum chassis
Furutech Gold-Plated IEC inlet
10 AWG silver-plated copper power path wiring
Proprietary hand-built EMI/RF filter
Custom hand-built "soft-start" circuit with 30-amp rated relay
50-amp rated terminal block
Standard with Vesuvius Power Cord
5.0 - 4 Furutech Gold 20-amp receptacles.
All contacts treated Caig DeoxIT Gold
Extensive internal vibration dampening
Dimensions: 19 x 8.5 x14 (WxHxD in inches)
Weight: 110 lbs.
Silver Circle Audio
3507 Shadow Bluff Court
Houston, TX 77082
Voice: (281) 870-8272