Pass Labs XP-20 User Manual

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November 25, 2011

XP-20 Owner’s Manual

XP-20 Owner’s Manual

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Introduction

The XP-20 is an ultra high quality line-stage audio preamplifier
featuring an improved hand held remote control and external
power supply electrically isolated from the analog circuits of the
preamplifier in a cosmetically matched second chassis.

The XP-20 like all Pass Laboratories products attempts to minimize
the number of components in the signal path, and yet retain
exemplary objective performance specifications. This pre-amplifier
pushes the edge of the art by exploring how much subjective quality
is obtainable with unique circuit elements applied in innovative ways.

The Pass Laboratories XP-20 along with the XP-10 pre-amplifiers
are the natural descendants to the highly acclaimed and successful X
series of Pass Laboratories line-stages represented by models X0.2,
X1 and X2.5.

The X series pre-amplifiers have received many highly respected and
well-deserved accolades since their introduction in 1997…. justifiably
so. More importantly they have provided a solid foundation from
which the current and newest product has evolved.

These new pre-amp offerings from Pass Laboratories objectively
sound and measure significantly better than their immediate
predecessors. These are the finest pre-amplifiers Pass Laboratories
has built to date, without question! Thank you for your purchase of
the XP-20.

The new XP series pre-amplifiers are more true to state of the art
recordings than our previous product. Given quality recordings,
these pre-amplifiers sound more dynamic, bass lines are more clearly,
cleanly, and accurately delineated, helping eliminate un-necessary
one note bass; instruments and voice are presented in a more refined
spatial envelope, and with better spectral balance. Fine nuances and
details, which frequently go un-noticed, now become apparent -­even in loud and highly complex musical passages.

The simple truth is that a decade of knowledge and experience
gained, coupled with new component technology, has enabled both
enhanced performance and listening satisfaction over the building
blocks we had available when the original X series pre-amplifiers
came to market. Pass Laboratories has not been shy about taking
advantage of these circuit innovations and new components in these
new pre-amplifiers. You will hear, and appreciate, these significant
sonic improvements in the XP series product.

XP-20 Owner’s Manual

Collectively, audiophiles tend to listen quite a bit differently today,

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than they did when the original X preamps were created, and the XP
line of product have all been designed to reflect those changes in
listening style.

Pass Laboratories has redesigned the remote control to allow
direct access to the most frequently wanted control functions, thus
simplifying and enhancing product operation. The new remote
control codes have been carefully selected to minimize the impact
on other remote controlled electronic devices, allowing for more
carefree product placement. Volume control steps on the new pre­amplifiers are more numerous and generally of smaller increments,
giving the listener a wider choice of listening levels to better
accommodate the wildly-fluctuating signal levels of current, verses
legacy, recordings.

Changing lifestyles dictate that many audiophiles now share family
space where music may be an adjunct to other activities. To better
serve the needs of these listeners, the newest Pass Laboratories
pre-amplifiers allow for significantly more precise volume steps and
greater attenuation at the very lowest volume levels.

So that these very low-volume listening levels have real world
practicality, the noise floor and very fine detail retrieval of these new
pre-amplifiers is dramatically superior to our previous product.

Frequently, the perception of increased detail comes at the cost of
equally increased grain or edginess in the music. With this new pre­amplifier, hundreds of hours of thoughtful listening and careful
adjusting have produced a product where the enhanced detail simply
comes through as greater spatial refinement and dynamic accuracy;
without any loss of musicality.

Bass definition is better than in pervious models, highly dynamic
passages typically have more weight, a more accurate leading edge
with increased control and the spectral balance is more finely
integrated top to bottom.

As good as the XP-10 is, the XP-20 performance metrics are
enhanced over those available in the XP-10 by virtue of a separate
and additionally regulated power supply. For the listener these circuit
enhancements will convey musical bass with significantly more
impact, articulation and timber accuracy. With well-recorded material
the XP-20 will present a more refined sound stage than the XP-10
with greater ability to accurately delineate instruments in their proper
spatial perspective of depth, width and height.

XP-20 Owner’s Manual

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We sincerely believe these are simply the best sounding pre-amplifiers
Pass Laboratories has ever built! Simply put the XP products deliver
the experience of a past musical event in a more believable sonic
panorama than anything we have previously brought to market.

Thank you for listening and giving us the opportunity to prove this
claim.

Advisory

There is an Extremely Small (but Non-zero) Chance That, Through
a Process Know as Tunneling, This Product May Spontaneously
Disappear from Its Present Location and Reappear at Any Random
Place within the Universe, Including Your Neighbor’s Domicile.
The Manufacturer Will Not Be Responsible for Any Damages,
Inconvenience or Mental Anguish That May Result.

There is a much higher probability that when you first plug your
new pre-amps power supply into the wall and listen to your favorite
selections that you will not be experiencing the full measure of
performance this product is capable of. These are high bias Class
A topology circuits and their performance is largely temperature
dependent.

We expect these circuits to heat up slowly through normal operation,
do not attempt to augment that heating by any artificial means.
Temperature and performance will slowly stabalize over the first 24 ­48 hours of operation and thereafter be at their sonic best. Be aware
however that if you unplug or otherwise remove power from the
unit that the warm up period starts afresh. Please give this product
at least 24 hours initial warm up time before attempting any critical
listening.

Set-up

XP-20 Owner’s Manual

A typical current draw for this product is 25 watts or less; the XP­20’s are designed to be powered up 100% of the time.

So much for the philosophy, physics and advantages, lets play music.

Please read and understand the operational instructions and safety
issues associated with this product. We go through great effort to
make a soundly engineered, and supurbly performing rugged product
of lasting duribility. We understand that things infrequently go
wrong, if you have any questions or problems please contact either
your dealer or the factory, we are here to support the product and
you, the user.

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As with all audio electronics the power cable should be the last thing
attached and the first one removed any time you hook up or remove
equipment from the signal chain. The DIN-25 umbilical cable
should never be connected or removed with the power supply chassis
plugged into house power.

The preamplifier has five sets of stereo input connections, both
single-ended and balanced output connections and a full function
remote control in addition to the normal complement of front panel
control functions.

The preamplifier’s voltage and current rating are indicated by affixed
tag on the rear of the preamplifier’s separate power supply. It will
indicate 240 volts, 220 volts, 120 volts, or 100 volts. A 1.0 amp
3AG slow blow fuse is provided with 100-120 volt units, and a

0.50 amp slow blow fuse is provided with 220-240 volt units. The
input frequency rating of the power supply is 50 to 60 Hz. The
preamplifier typically draws approximately 25 watts of power from
the utility mains during operation. Please verify that the indicated
voltage requirement of this preamplifier’s power supply is consistent
with the utility voltage at your location.

In’s and Out’s

We have provided a standard IEC AC power cord that fits into the
IEC 320 line receptacle at the rear of the power supply chassis. The
preamplifier and power supply is equipped for operation with an
earth ground provided by the users AC outlet. Do not defeat this
safety ground. The chassis and circuit ground of the preamplifier is
connected to earth through a power thermistor, which gives a ground
connection for safety but helps avoid ground loop related noise
issues. Please connect the power supply to the preamplifier chassis
by the supplied umbilical before plugging the power supply into
the wall. Conversely please unplug the power supply from the wall
before disconnecting the umbilical cable.

There are a total of five inputs. Two of the five inputs are balanced
XLR only. The other three inputs are single-ended only. The XP-20
also has a “Tape Loop” with single ended inputs and outputs. There
are three pairs of outputs available with identical gain structure. One
pair Balanced, two pairs single-ended. You may use more than one
output at a time.

The single ended outputs are paralleled, but under most
circumstances will drive several devices at once, with no anticipated
ill effects by virtue of the XP-20’s low output impedance and high
current capability. The balanced outputs are derived from their own

XP-20 Owner’s Manual

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