Grace LUNATEC V2 Owner's Manual

OWNERS MANUAL

LUNATEC V2

MICROPHONE PREAMPLIFIER

PO Box 204 Boulder, CO. 80306

voice: 303.443.7454

fax: [phone]

email: [e-mail]

Revision A December, 1998

© Copyright 1998, Lunatec LLC

Thank you for purchasing the Lunatec V2 portable microphone preamplifier. It is
designed and built to be extremely reliable and easy to use. This owner's manual includes
important setup and operation instructions. Please take the time to familiarize yourself
with these instructions which will help to avoid most common user problems.

Grace Design has been building professional audio products for the recording
industry for over ten years. During this time the circuit technology embedded in the
Lunatec V2 has evolved through a process of extensive listening, testing and refinement.
Regardless of what audio sources you plan to record, the Lunatec V2 will faithfully serve as
an invisible link between your microphone and recorder device. We hope it helps you
achieve a new level of excellence in your audio recordings.

FEATURES OF THE LUNATEC V2 PREAMPLIFIER

•Stereo preamplifier circuit

•11 Position gain control

•10-60dB gain range

•10dB trim control

•48Volt Phantom power for microphones

•Signal and Peak LEDs

•Two position High Pass Filter

•Mid-Side recording matrix

Figure 1. V2 Front Panel

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FRONT PANEL CONTROLS

GAIN CONTROL Each gain control has 11 positions and adjusts the voltage gain from
10dB to 60dB in 5dB steps.

TRIM CONTROL The trim control provides 10dB of continuously variable output
attenuation. In the fully clockwise position the trim is at unity (no attenuation). In the fully
counter-clockwise position the trim is at -10dB. For reference, the 3 o’clock position is -4dB
and the 12 o’clock position is -8dB. The trim control should be left in the fully clockwise
position during normal recording.

PHANTOM POWER This switch provides 48 volts to power condenser microphones. The
phantom power switch (labeled +48) connects the +48V power supply to pins 2 and 3 on
the XLR input connector. Alternatively, the V2 can be configured to provide 12V Parallel
power. Please contact the factory for information on this option.

PEAK INDICATOR The LED peak indicator, which monitors the signal between the input
and output amplifiers, illuminates the green LED at -14dBu and illuminates the red LED at
+16dB (10dB before clipping).

HIGH PASS FILTER (labeled HPF) Sometimes referred to as a bass roll-off, the HPF uses
a three position toggle switch to select two different low cut corner frequencies and an OFF
position. Position 1 is the higher cutoff frequency and Position 2 is the lower cutoff
frequency. Internal jumpers allow for selection of either 6dB/octave or 12dB/octave slope.
The cutoff two frequencies can be set at 50Hz/100Hz or 75Hz/125Hz. Selecting HPF
switch position 1 sets the roll-off to the higher frequency while switch position 2 sets the
roll-off to the lower frequency. The 12dB/octave filter employs a transitional Thompson-
Butterworth response for the best combination of passband flatness and time domain
response. See section II for detailed jumper setting information.

POWER SWITCH The power switch connects power from the DC input connector to the
preamplifier circuitry. If the preamplifier is connected to a charged battery or other DC
power supply the POWER LED will illuminate.

POWER LED Indicates that the V2 is turned on and connected to an adequate power
source. NOTE: The 6 Volt V2 automatically turns off if the battery or power source voltage
drops below 5.5V. The 12 Volt V2 automatically turns off if the battery or power source
voltage drops below 11.0V.

LOW BATT For the 6 Volt V2 the low battery indicator flashes if the battery voltage drops
below 5.75V. For the 12 Volt V2 the low battery indicator flashes if the battery drops below

11.5V.

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