Pass Labs pre-amplifier - Manual (Page 3)

3 X0.2 Owner’s Manual
The pre-amplifier consists of three machined aluminum chassis; it
has five sets of input connections, two sets of outputs, both single-
ended and balanced, a tape loop and a full function remote control
unit that mirrors the front panel functions.
The power supply control chassis has a 5-way binding post that is
used for remote amplifier turn-on. The pre-amplifier’s voltage and
current rating are indicated by the affixed tag on the bottom of the
pre-amplifier’s power supply control chassis. This tag will indicate
either 240 volts, 220 volts, 120 volts, or 100 volts. A 0.5 amp 3AG
slow blow fuse is provided with 100-120 volt units, and a 0.25 amp
slow-blow fuse is provided with 220-240 volt units. The frequency
rating of the X0.2 power supply is 50 to 60 Hz. This pre-amplifier
typically draws 30 watts during operation. Please verify that the input
power rating as indicated on your unit is consistent with that supplied
in your area before attempting hook up.
The remote control is powered by two (2) factory installed AAA
batteries.
The individual gain channels connect to the power supply control
unit with four (4) necessary cables and to each other with one
optional cable. These cables must be installed before the
preamp is powered up. The cable jacks are clearly labeled on
the rear of each chassis and are style and gender specific so as to
minimize opportunity for mis-connection.
Both gain channels are identical electrically, the only difference is the
color of the identifying rings under the RCA connectors. The right
channel is identified by red rings under the RCA’s connectors and
the left by white rings. Additionally the right gain stage chassis has a
female XLR marked “mono” and the left gain control chassis has a
male XLR marked “mono” as a further identifier.
The X0.2 takes maximal advantage of four identical gain paths
(two identical paths per channel) very much unlike the typical two
gain path (one signal path per channel) pre-amplifier you may be
familiar with. Almost without exception traditional consumer audio
pre-amplifiers, unlike their science and industry counterparts have
maintained a single signal path per channel (two identical aths in a
stereo pair).
In order to manage balanced signals these two gain path pre-
amplifiers must utilize phase combining networks to process
incoming signals and subsequently drive outputs via phase splitting
circuits to re-establish a quasi-balanced signal. This manipulation of
Setup