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Introduction:
Wayne Colburn and the Pass Labs team were allowed to build the most advanced, best
sounding phono-stage they could imagine; the phono-stage they all wished to have for
their own homes. The X Phono is the result of this ambitious effort.
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The X Phono is a true "dual-mono" design, the only component shared between channels
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other than casework, being the
power connection to house power.
AC
Once past the power cord the
mains feed left and right channel power supplies, each
AC
totally independent from one another with their own dedicated transformer,
fi
ltering and
regulation. The control section has its own regulated power supply as well.
Building upon the dual mono theme and topology each of the three inputs feature left and
right gain channels, each on a separate, ceramic substrate circuit boards (6 circuit boards).
This total independence starting at the power cord and continuing right through to the
output connectors guarantees minimal noise and negligible channel to channel "cross-talk".
The result is listening to music emerging from a quieter background and blooming into a
richer, more precise soundstage.
Signal ampli
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cation from the phono cartridge inputs occurs prior to any input switching.
This pre-ampli
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cation of the incoming signal prior to routing greatly reduces corruption
of the low level analog information.
From the front panel of the X Phono you can select precise resistive loadings from 30
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ohms through 47k-ohms, capacitive values from 100 pF through 750 pF in addition to gain
of 56 dB, 66 dB or 76 dB. Blue
's on the front panel indicate the loading values and
LED
gain settings.
For any input, choose the loading and gain settings best suited to that cartridge and push
the "save" button on the front panel. Those values are now saved in memory and
associated with that input. They will be recalled and applied to that input any time you
select that input.
Frequently we come upon recordings which bene
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t from a slightly different cartridge
loading, as for example slightly more capacitance. From the saved value it is quite trivial to
change the capacitance (or resistance) loading for that one
and then revert to the saved
LP
settings in memory by reselecting the same input, which restores the saved values.
While internally this makes for a very complex piece of hardware, it was of paramount
concern was to make operation as intuitive and simple as possible. We believe that this
goal has been achieved and the result is a piece which should not require much in the way
of operational instructions.
Mute Function, the mute is applied automatically as inputs are selected and de-selected and
during input or loading option changes. This allows for switching of the various functions
with as few distractions as possible. The mute function may be applied manually, should
you need to pay attention to something else or simply want to queue a recording silently.
Simply press the mute button. The blue
above the button indicating it is active
LED
The High Pass Filter can be left off for most recordings. When selected, the
directly
LED
above the button will show blue, The High Pass Filter rolls off the low end response of
the X Phono at 6dB per octave. The resulting 3dB roll-off at 20 Hz. maintains much of
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the bandwidth you desire, while minimizing various low frequency residual artifacts in less
than perfect recordings. De-selecting the Hi-Pass function allows more of what is on the
recording to come through.