Grace 101 Owner's Manual

2434 30th street, boulder, CO 80306-0204 USA

tel [phone] fax [phone]

[e-mail] / www.gracedesign.com

model

single channel microphone preamplifi er

owner’s manual Rev C

all contents © Grace Design/ Lunatec LLC

101

contents

Features 3

Front Panel Controls 4

Preamplifier Connections 5

Operation 6

Trim Control 6

Rackmounting 6

Cable Diagrams 7

Specifications 8

Warranty Information 9

Manual Revisions 10

Welcome and thanks for purchasing the Grace
Design model 101 microphone preamplifier and
DI. We build all of our products to be completely
reliable and easy to use, so you can concentrate on
making great recordings, not struggling with com­plicated equipment or difficult product manuals.

While the model 101 is completely straightfor­ward to use, we do ask that you spend a little time
familiarizing yourself with this product manual to
help avoid any common user difficulties.

In the event that you do encounter any techni­cal difficulties with this or any of our products,
feel free to call at 303-443-7454. Our office
hours are 9 to 5, Monday through Friday, MST,
or you may email any technical questions to:
[e-mail].

Also, please check out our web support page
listed below for the latest Grace Design product

information, owners manuals and technical docu­ments. Grace Design has been building audio­phile-quality products for the recording industry
over 15 years. The technology in the model 101
and all of our products has evolved through a pro­cess of extensive listening, field-testing and careful
refinement.

Your new model 101 preamplifier represents a re­markable combination of absolutely pristine audio
performance, robust mechanical construction and
bombproof reliability at a reasonable price.

Regardless of what audio sources you plan to
record, your model 101 will faithfully serve as an
invisible link between your microphone or instru­ment and recording device.

We sincerely hope our products help you achieve
a new level of excellence in your work!

-The Grace Design Team

model

101

owner’s manual

http://www.gracedesign.com/support/support.htm

page 2

model 101 features

• fast, musical transimpedance amplifier architecture

• fully balanced, transformerless XLR microphone input

• high impedance 1/4 inch instrument DI input

• balanced XLR and 1/4 inch TRS outputs

• gold plated XLR input and output connectors

• 11 position precision silver contact rotary switch gain control

• high quality conductive plastic 10dB output trim control

• 75Hz 12dB/octave transitional Thompson-Butterworth high pass filter

• two color, bi-phase LED peak meter shows signal present and peak

• optional extended gain range input (10-70dB) for ribbon microphones

• 1/2 width 1U chassis / two units fit together in a standard 1U rack tray

• sealed gold contact relay for instrument/mic switching

• high precision active balanced output circuit

• no electrolytic capacitors in the signal path

• ultra clean 48 Volt phantom power

• minimal internal signal wiring

• 5 year warranty on parts and labor

model

101

owner’s manual

page 3

front panel controls

1/4 inch TRS instrument HI-Z input
Designed to accommodate a wide variety of high impedance
input sources, making the 101 an excellent choice as a DI box
which will flawlessly preserve the sound of the instrument.

48V PHANTOM POWER
This switch provides 48 volts to power condenser
microphones. The phantom power switch (labeled 48V)
connects the +48V power supply to pins 2 and 3 on the XLR
input connector.

GAIN CONTROL
The gain control has 11 positions and adjusts the voltage
gain on the microphone input from 10dB to 60dB in 5dB
steps. When using the instrument input, the gain range is
–10dB to 40dB in 5dB steps. NOTE: If you ordered the high
gain version of the 101 for use with ribbon microphones,
the gain range of your unit on the microphone input is 20dB
to 70dB in 5dB steps and the gain range of the instrument
input is 0dB to 50dB in 5 dB steps.

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). It is located between the

GAIN and TRIM controls.

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.

HIGH PASS FILTER

(labeled HPF) Sometimes referred to as a bass roll-off, the

high pass filter rolls off at 75Hz. This 12dB/octave filter

employs a transitional Thompson-Butterworth response

for the best combination of passband flatness and time

domain response.

POWER SWITCH

The power switch connects power from the DC input

connector to the preamplifier circuitry. When depressed,

the amber POWER LED will illuminate.

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101

owner’s manual

page 4