The need for a preamp
when most sources already have enough output to drive a
power amp is really related to the need for an accurate
and truly transparent volume control. Accurate in
the sense of not introducing non-linear distortions and
accurate in that it can track all possible output
settings while still keeping perfect channel to channel
balance without having to use a separate balance
control. Placette Audio solves this problem with a
stepped volume attenuator that provides 125 discrete
volume steps and by using only the very costly Vishay S
102 resistors. These incomparable resistors simply do
not damage the audio signal. They pass it along intact,
unlike any other resistor.
The sonic value
of the Vishay S 102 is well known but the cost is so high
(several dollars each instead of a just a few cents!) that some
builders use them only in certain parts of the attenuators. For
example, sending the audio signal through a single Vishay and
then grounding through something else. This doesn't work. The
only way to get the clarity, purity and transparency that these
resistors are known for is to use them exclusively, in every
part of the audio circuit or control. When used exclusively in
this way, Vishay resistors more than triple the cost of any
product they are used in! But when you hear your system without
the grain, the brightness and the smearing common to lesser
controls, you will readily agree that they are worth every cent!
Another important
quality of Placette Volume Attenuators is that they provide a
constant input impedance. This is important because your
source should always see the same load at every volume setting
to keep it from sounding different at different volume settings.
And that load should be one that is as resistive at audio
frequencies as possible. Again, only Vishay's offer an almost
totally resistive load so that your source is always playing
into the easiest possible load. You will then have full access
to everything that your sources are capable of offering.
In order to keep all
active circuitry out of the volume control, all switching in the
attenuator is done with ultra-sensitive relays. Active
switching, although much less expensive to build, can introduce
non-linear distortions that translate into listening errors that
mean irritation and listener fatigue.
The perfect loading
of your sources coupled with the inherent transparency of the
Vishay
resistors means that Placette Linestages and passive Volume
Controls actually go a little beyond total transparency in the
sense that they will enable your present source components to
sound far better than you ever though possible and then deliver
that undistorted signal to your power amplifiers.
Because we sell
direct, we pass that savings on to our customers in the form
of much higher parts costs and absolutely unrivaled performance.
If you value ultra-high-fidelity, then nothing else even comes
close. At any price. We guaranty it!
Guy Hammel, Placette Audio |