T L Audio
CRIMSON SERIES
User Manual
VP-3051
VOICE PROCESSOR
Tony Larking Professional Sales Limited,
Letchworth, England.
Tel: 01462 490600. International +44 1462 490600.
Fax: 01462 490700. International +44 1462 490700.
INTRODUCTION
The T L Audio Crimson Series utilises low noise solid state circuitry to produce audio
processing units offering very high quality signal paths with comprehensive control
facilities. Crimson series units are straight-forward to operate, and offer excellent
value for money.
The VP-3051 is a single channel voice processor, combining a high quality
microphone pre-amplifier, four band equaliser and a compressor. All parameters of the
compressor are variable, and a link facility enables two units to be operated in stereo
mode. The bargraph meter may be used to display output level or gain reduction.
The block diagram of the unit is shown in fig.1. Each channel has four input sources balanced microphone and line inputs via XLR connectors, plus an unbalanced line
level input via a jack socket, and an instrument input also on an unbalanced jack
socket but located on the front panel where it provides a convenient means of patching
a guitar or keyboard directly into the processor. The gain of the input stages is
controlled by a centre-detented control, calibrated for 0dB nominal gain from the line
input sources at the centre and providing up to 60dB of microphone gain. The
instrument input has a sensitivity switch associated with it, to match the gain to a low
level pickup (e.g. a passive guitar or microphone) or a higher output source such as a
keyboard or active guitar, and is also controlled by the input gain potentiometer.
The equaliser has four bands, providing up to 15dB of cut and boost at the selected
frequencies. The “EQ PRE” switch positions the equaliser before (pre) or after (post)
the compressor. The sidechain monitors the output of the compression stage, and
generates a control signal which varies the attenuation of the compressor. The
sidechain processing includes fully variable control of the compressor threshold and
ratio, plus switched fast and slow time constants for attack and release. Frequency
dependant compression (for example de-essing) may be achieved by placing an
equaliser into the sidechain insertion point.
An independent gain make-up control is provided, to retain the subjective loudness of
a compressed signal, plus an overall master output level control. The output control
has a nominal 0dB of gain at its centre, with up to 18dB of further gain available to
ensure full modulation of digital recorders. The output is via a balanced XLR socket at
a nominal level of +4dBu, with an unbalanced output on a jack socket at a nominal
level of -10dBu. An LED bargraph meter is provided, which may be switched to
monitor the output signal level or compression applied.
Please read this manual fully before installing or operating the Voice Processor.
PRECAUTIONS
The T L Audio VP-3051 Voice Processor requires very little installation, but like all
electrical equipment, care must be taken to ensure reliable, safe operation. The
following points should always be observed:
- All mains wiring should be installed and checked by a qualified
electrician,
- Ensure the correct operating voltage is selected on the rear panel
before connecting to the mains supply,
- Never operate the unit with any cover removed,
- Do not expose to rain or moisture, as this may present an electric
shock hazard,
- Replace the fuse with the correct type and rating only.
Warning: This equipment must be earthed.
INSTALLATION
AC Mains Supply.
The unit is fitted with an internationally approved 3 pin IEC connector. A mating
socket with power cord is provided with the unit, wired as follows:
Brown: Live.
Blue: Neutral.
Green/Yellow: Earth (Ground).
All mains wiring should be performed by a qualified electrician with all power
switched off, and the earth connection must be used.
Before connecting the unit to the supply, check that the voltage selector switch on the
rear panel is correctly set. The unit may be set for 115V (accepting voltages in the
range 110V to 120V, 60Hz AC), or to 230V (for voltages in the range 220V to 240V,
50Hz AC). Adjustment to the operating voltage should be made by sliding the selector
switch left or right with a small screwdriver until the desired voltage is displayed. The
mains fuse required is 20mm anti-surge, 1AT rated at 250V. If it ever necessary to
replace the fuse, only the same type and rating must be used. The power consumption
of the equipment is 30VA.
Warning: attempted operation on the wrong voltage setting, or with an
incorrect fuse, will invalidate the warranty.
Audio Operating Level.
The voice processor is equipped with inputs and outputs suitable for connection to a
wide variety of other audio equipment. Generally, the balanced XLR connections will
be required for interfacing to other professional equipment, where the operating level
(line-up level or nominal level) will be +4dBu, or approximately 1.2V rms. The
unbalanced jack connectors are generally intended for interfacing to semi-professional
equipment and have an operating level of -10dBu, or about 225mV rms.
The processor may be used to change between operating levels, for example by
connecting the unbalanced output of a semi-pro mixing console to the processor’s
unbalanced input, and taking the balanced output of the processor to the balanced
input of a tape machine at +4dBu. All line level inputs and outputs of the processor
may be used simultaneously if required. Balanced interconnection is always preferable
to obtain the best headroom and noise rejection, but can only be used if the other
equipment in the chain, e.g. the mixing console, also has provision for balanced
connections.
Audio Inputs.
Microphone Input.
The microphone input is via 3 pin female XLR connector, suitable for balanced or
unbalanced microphones. The mating connector should be appropriately wired as
follows for balanced or unbalanced operation:
Balanced inputs:
- Pin 1 = Ground (screen).
- Pin 2 = Signal Phase (also known as “+” or “hot”).
- Pin 3 = Signal Non-Phase (“-” or “cold”).
Unbalanced inputs:
- Pin 1 = Ground (screen)
- Pin 2 = Signal Phase (“+” or “hot”).
- Pin 3 = Signal Ground.
Line Input.
The line level input is also via a 3 pin female XLR connector, suitable for balanced or
unbalanced line sources at a nominal level of +4dBu. The mating connector should be
appropriately wired as follows for balanced or unbalanced operation:
Balanced inputs:
- Pin 1 = Ground (screen).
- Pin 2 = Signal Phase (also known as “+” or “hot”).
- Pin 3 = Signal Non-Phase (“-” or “cold”).
Unbalanced inputs:
- Pin 1 = Ground (screen)
- Pin 2 = Signal Phase (“+” or “hot”).
- Pin 3 = Signal Ground
When using unbalanced signals, the signal ground may be obtained by linking pins 1
and 3 in the mating XLR connector. If this connection is not made, a loss in level may
result.
Unbalanced Line Inputs.
An unbalanced line level input at a nominal level of -10dBu is also provided, on a
0.25” mono jack socket. The mating plugs should be wired as follows:
- Tip = Signal Phase (“+” or “hot”).
- Screen = Ground.
Auxiliary Inputs.
A 2 pin (mono) jack plug is required, which should be wired as follows:
- Tip = Signal Phase (“+” or “hot”).
- Screen = Ground.
The auxiliary input is suitable for direct connection of instruments including guitars
and keyboards. Good quality screened cable should be used, particularly for
microphone or low level sources, to prevent hum or noise pickup.
Insertion Point.
The insertion point is interfaced via a 3 pin, 0.25” switched jack socket on the rear of
the unit. The pin connections are:
- Sleeve = Ground,
- Tip = Send,
- Ring = Return.
The insertion point is unbalanced, and operates at a nominal level of -2dBu . If used
as an additional send only (e.g. as a send to a tape machine or monitor mixing desk),
the Tip and Ring should be wired together, to preserve the signal path through the
insertion point. When used in this manner, the send will be post-compressor.
Balanced Output.
The output is via a balanced, 3 pin male XLR connector. The mating connector
should be wired as follows:
Loading...