VAC Signature Preamplifier Mk II - Manual (Page 8)

FRONT PANEL CONTROLS
Although most of the front panel controls (Volume, Power, Mute) are self explanatory, VAC
has outfitted this unit with several advanced features which bear further description:
Phono Section: When fitted, input “PHONO" is connected to a discrete, pure tube phono
preamplifier, providing 44 dB of gain, suitable for use with MM (moving magnet) and many
high-output MC (moving coil) cartridges. An MC step up interface can be switched in for
64 dB of gain, making the Signature Preamplifier suitable for most low output cartridges.
Monitor: The small knob found at the lower left-hand corner of the faceplate switches
between “Source” and “Tape”. In the “Source” position, input selection is determined by
the Source Selector Switch. In the “Tape” position, the Source Selector is overridden, and
the Tape inputs are activated.
Cinema: The small knob found at the upper left-hand corner of the faceplate switches
between “Source” and “Cinema” (home theater pass-through mode). In the “Source”
position, input selection is determined by the Source Selector Switch. The “Cinema”
position provides access to one of the Signature Preamplifier’s most unusual feature. When
set in the “Source” position, input choice is governed by the Input Selector switch. This is
the normal setting, and enables the unit to be used as a typical preamplifier. Rotating the
control clockwise to the “Cinema” position bypasses all preamplifier controls (including
volume) and passes the output from your surround sound processor (i.e., the front left- and
right-channel outputs of a multichannel processor) directly to your power amplifier. In this
case, the users’ analog stereo sources would be connected, as usual, to the line, phono
and tape inputs. A/V inputs (DVD, Laserdisc, DSS, etc.) would be connected to the home
theater processor, and the processor’s main outputs would be connected to the pair of
rear panel RCA jacks labeled “Home Theater Direct”. When the control is set to the “Cinema”
position, the Signature Preamplifier functions as a pass-through ONLY, and is controlled by
the external processor, preamplifier, or other component connected to the “Home Theater
Direct” inputs.
Mute: This knob is spring loaded; moving the control clockwise will toggle between the
“Mute” and “Operate” condition. When muted, the VAC logo will be red; when un-muted,
it will be blue. On occasion the preamplifier may seem not to have responded to a turn of
the “Mute” knob; this is due to “contact bounce” in the switch. Simply turn the knob again
until the desired condition is attained.
Meters: The power supply has two backlit meters. One monitors the output voltage of the
heater supply to the line stage, the other monitors the high voltage supply to the line stage.
These will vary somewhat due to power line voltage, and, to a lesser degree, tube
condition. The target condition has the needle aligned with the ball indication in the center.