This is what is in PS Audio's latest newsletter regarding PC's:
Why amp manufacturers say "don't"!
I've been asked to writer a little piece explaining why some amplifier
manufacturers still insist on putting warnings in their owner's manuals
about connecting their equipment to a power conditioner. New owners are
warned to plug directly into the wall because these designers "built
their equipment to sound best when powered without any interference from
an inline power conditioner". Or so the line goes.
Over the last 30 something years of designing amplifiers myself, I too
have been guilty of writing the same thing for PS Audio amplifiers. So
I can relate to their thinking processes and understand why they would
warn folks.
First, let's get something clear: no amp manufacturer or designer wants
anything more than to make sure you are happy with your amp purchase.
Let's face it; it's in their best interest for you to love their
product. So, to many designers it's just a safe bet to have as few variables
as possible and so it's a bit of CYA. Better safe than having to answer
a bunch of questions when things don't go right.
But why did I write those warning words before PS Audio invented the
world's first power regenerator? Simple: up to that point most power
conditioners made things worse. Unfortunately, not a lot has changed in the
meantime so today's amp manufacturers figure it's a safe bet to tell
their customers "just plug directly into the wall".
I remember, in fact, the very first power conditioners I listened to
(way back when) and my reaction was always the same: yuck. Bleached,
restricted sound. Gimme the wall socket back and quick!
But progress was at hand: to my delight, Bruce Brisson's MIT company
came out with the first power conditioner box that worked. It was called
the Z Stabilizer and it was a parallel device (nothing in series) that
didn't do a whole lot, but what it did - it did well and this box was
the piece that got me thinking about the possibilities of AC power "done
right" in the first place. Thanks Bruce!
So, with most power conditioners adding something sonically destructive
in series with the AC line, it's no wonder that some amp manufacturers
still insist on folks going with a direct plug in scenario. In fact,
think about this: even if the power conditioner you use doesn't actually
do anything good or bad (I'm not pointing fingers here, but they exist)
you have just added another power cable and its connectors to the amp
chain. Can't be better.
Several power conditioner manufacturers have "solved" this problem of
destructive series elements in the AC path by going the route of the old
Z Stabilizer: parallel. In a parallel processor like the Shunyata,
Richard Grey and Audience products (as examples) there's little to no
restriction to the power path and so damage is minimal. That's the good
news: unfortunately, there's not much real conditioning that can take place
with a parallel device. Just the nature of power physics.
But not all series devices are bad. If you're going to use a series
device so you can achieve a greater level of cleaning, like our UPC-200 or
UO products, it is critical that they do not restrict the power with
over-filtering (as so many do). One by one we've had great success
demonstrating how these properly designed products don't degrade the sound,
but rather improve it. It just takes time for word to get around. Over
filtering produces the bleached and anemic sound I wrote about above.
A regenerator, like the Power Plant, is a horse of a different color
however. Here, the opposite of restriction is happening because compared
to the wall socket, a Power Plant is less restrictive! That's right,
the raw wall socket is more restricted than a Power Plant's output - so
plugging directly into the wall outlet is never as good as a Power Plant
because we supply stored energy that regulates and lowers impedance to
the connected equipment. This stored energy is NOT available through
the wall socket. So amp manufacturers are actually hurting their case
when they lump all conditioners together into one bag of 'no, no's'. Not
all products fall into the same category of performance.
In any case, I thought it might be instructive to know why amp
manufacturers continue to suggest folks plug straight in. They're being safe.
Let's face it, there's plenty of bad power conditioning equipment out
there still and yes, it's worse to use a bad conditioner than going
straight into the wall. Beware.
