Unbalanced Operation; Using The Vt-737Sp; Using The Mic Preamplifier - Avalon VT-737SP Operation Manual

Operation and
Controls

4.3 Unbalanced Operation

The Vt-737sp can also be used in unbalanced
system by grounding the unused input or
output pin. For mic or line input, tie pin 3 to
pin 1 (ground). For output from the Vt-737sp
to an unbalanced input leave pin 3 floating.
Either the high or low pins can be used to
carry the unbalanced signal.

4.4 Using the Vt-737sp

The Vt-737sp features a combination of Class
A tube preamplifiers (mic, line, and instru-
ment), tube opto-compressor, and discrete
parametric equalizer perfect for controlling
and enhancing your signal in many ways.
4.4.1 Using the Preamplifier
The Vt-737sp has a flexible and musical
preamplifier. You can set your levels in a
number of ways to achieve different tones
and colors. The following are helpful hints in
setting initial levels for signal integrity, lowest
noise and optimal sonic performance.
Avalon Vt-737sp Operation Manual
1. Turn the INPUT selector switch to the desired
input source (MIC, INSTRUMENT or LINE) and
plug in to the corresponding input.
2. Set all knobs to unity (center 0) and disen-
gage all push button switches. When the VU
meter is disengaged it measures output signal
level.
3. Turn the PREAMP control fully counterclock-
wise (minimum level).
4. Set the OUTPUT control to unity "0" position.
5. If you are using a condenser mic which
requires phantom power, engage the +48V
button (illuminates "ON")
6. Slowly turn PREAMP control clockwise while
sending signal through the Vt-737sp. You should
begin to hear signal and see slight VU meter
indication. Adjust the incoming signal level so
that the maximum peak is approximately zero on
the VU meter (or until desired sound is
achieved).
Note: On the Vt-737sp, the PREAMP GAIN con-
trol should be used like a "fader" control. For a
typical medium output condenser microphone,
optimal level occurs when the PREAMP GAIN
control is set to around +30dB without the HIGH
GAIN switch engaged.
7. Use the OUTPUT control to set the level going
to the recording device.
8. If the signal level is too low (even with the
PREAMP and OUTPUT controls near or at maxi-
mum) turn the PREAMP control back to starting
positions (PREAMP GAIN fully counter clock-
wise and OUTPUT at unity) and engage the
HIGH GAIN button. Slowly turn PREAMP control
clockwise again until sufficient signal level is
attained.
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