Rolls ADB3b User Manual

ADB3b

Stereo Tube Direct Box

CHANNEL ONE

GND
LIFT

- 00 dB 0

INPUT INPUT

+20 dB

-20 dB

ADB3b

The tube direct box is the DI of choice for hundreds of
studios, engineers, producers, and artists the world o ver .
The clear , warm quality of the tube maximizes the sound
of musical instrument pickups and interf aces. The ADB3 is
a two-channel active impedance matching device utilizing
a 7025 vacuum tube. Unlike solid state active direct
boxes, the ADB3 delivers a warm, slightly compressed
signal due to the natural softening characteristics of tubes.
Each channel features two 1/4" inputs, an XLR output, a
Ground Lift switch, a 0 to - infinity Pad control, and a +20/­20 dB input gain switch.

The ADB3 is housed in a heavy gauge steel chassis for
durability, and is easily mounted to any standard rack tra y.
It is ideal for:

Bass Players, for interfacing between a preamp and a
mixing board to achieve that warm, tight sound.

Acoustic Guitarists, the high impedance of the ADB3
insures a perfect pickup match to provide a smooth,
natural sound.

Electric Guitarists, for a clean DI sound, the ADB3 has a
clear, warm sound that retains all of the natural brilliance
and harmonics for a perfect electric guitar tone.

CHANNEL TWO

+20 dB

-20 dB

- 00 dB 0

GND
LIFT

PWR

INPUTGND LIFTGAININPUT GND LIFT GAIN

Synthesizers, drum machines and samplers, the ADB3
warms up the sound and provides an ideal interface for the
variety of synthesizer output levels and impedances.

Digital Recording, for eliminating the harsh, often brittle
digital sound.

SPECIFICA TIONS

Frequency Response: -20 dB Gain: 20Hz - 40kHz, +/-1dB

+20 dB Gain: 50Hz - 20kHz, +/-3dB

THD: .03% (0dB in, -20dB Gain)

1% (-10dB in, +20dB Gain)
Noise Floor: >90dB (Gain switch in)
Connectors: Input: 1/4” unbal.

Output: XLR transformer bal.
Input Impedance: 100K Ω
Output Impedance: 600 Ω
Maximum Input Level: +20dB (Gain switch out)

-10dB (Gain switch in)
Maximum Gain: +20dB
Size (WxHxD) 7.6” x 1.6” x 5.4”

(194mm x 40mm x 135mm)
Weight: 2.5lbs (1.135kg)
Po we r: 12V AC 300ma

(Adapter included in US models)

MODEL ADB3

12VAC
300 MA

MADE IN U.S.A

Bellari is a division of
ROLLS Corporation
5143 South Main Street
Salt Lake City, UT 84107
11/98

INPUT

OUTPUT

CHANNEL TWO

OUTPUT

INPUT

SERIAL NUMBER

ADB3-

CHANNEL ONE