Bellari ADB3B User manual

OWNERS MANUAL
ADB3b
Stereo Tube Direct Box
Salt Lake City, UT
email: [email protected]
web site: www.rolls.com
4/98
- 00 dB 0
PWR
INPUT
GND LIFT
GAIN
INPUT GND LIFT GAIN
GND
LIFT +20 dB
-20 dB
ADB3b
CHANNEL ONE CHANNEL TWO
S tereo T u be
D irect B ox
INPUT PAD INPUT PAD
- 00 dB 0
GND
LIFT
+20 dB
-20 dB
LIMITED WARRANTY
This product is warranted to the original consumer purchaser to be free from
defects in materials and workmanship under normal installation, use and service for a
period of one (1) year from the date of purchase as shown on the purchaser’s receipt.
The obligation of Rolls Corporation under this warranty shall be limited to
repair or replacement (at our option), during the warranty period of any part which
proves defective in material or workmanship under normal installation, use and service,
provided the product is returned to Rolls Corporation, TRANSPORTATION CHARGES
PREPAID. Products returned to us or to an authorized Service Center must be accompa-
nied by a copy of the purchase receipt. In the absence of such purchase receipt, the
warranty period shall be one (1) year from the date of manufacture.
This warranty shall be invalid if the product is damaged as a result of
defacement, misuse, abuse, neglect, accident, destruction or alteration of the serial
number, improper electrical voltages or currents, repair, alteration or maintenance by
any person or party other than our own service facility or an authorized Service Center,
or any use violative of instructions furnished by us.
This one-year warranty is in lieu of all expressed warranties, obligations or
liabilities. ANY IMPLIED WARRANTIES, OBLIGATIONS, OR LIABILITIES,
INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF MER-
CHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, SHALL BE
LIMITED IN DURATION TO THE ONE YEAR DURATION OF THIS WRITTEN
LIMITED WARRANTY. Some states do not allow limitations on how long an implied
warranty lasts, so the above limitation may not apply to you.
IN NO EVENT SHALL WE BE LIABLE FOR ANY SPECIAL, INCIDEN-
TAL OR CONSEQUENTIAL DAMAGES FOR BREACH OF THIS OR ANY OTHER
WARRANTY, EXPRESSED OR IMPLIED, WHATSOEVER. Some states do not allow
the exclusion or limitation of special, incidental or consequential damages so the above
limitation or exclusion may not apply to you. This warranty gives you specific legal
rights, and you may also have other rights which vary from state to state.
SPECIFICATONS
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)
Power: 12VAC 300ma (Adapter included in US models)

Congratulations and thank you for purchasing the ADB3b Stereo Tube Direct
Box. The tube direct box is the DI of choice for hundreds of studios, engineers,
producers, and artists the world over. The clear, warm quality of the tube
maximizes the sound of musical instrument pickups and interfaces. The ADB3b
is a two-channel active impedance matching device utilizing a 7025 vacuum
tube.Unlike solid state active direct boxes, the ADB3b 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. Please take a moment
and read this manual carefully. We sincerely hope this product provides you with
years of reliable service.
FRONT PANEL
PWR LED: Indicates the ADB3b is on.
NOTE: Channel One descriptions are identical to Channel Two.
INPUT JACK:1/4" unbalanced jack for instrument, line, or speaker level
signals.
GND LIFT SWITCH: Disconnects the ground from pin 1 of the output
jack.
PAD CONTROL: Adjusts the amount of input level from off to 0 dB.
GAIN:When in, the gain of the tube circuit is -20 dB.When out, the gain
is +20 dB.
- 00 dB 0
PWR
INPUT
GND LIFT
GAIN
INPUT GND LIFT GAIN
GND
LIFT +20 dB
-20 dB
ADB3b
CHANNEL ONE CHANNEL TWO
S tereo T u be
D irect B ox
INPUT PAD INPUT PAD
- 00 dB 0
GND
LIFT
+20 dB
-20 dB
REAR PANEL
NOTE: Channel One connections are identical to Channel Two.
INPUT: 1/4" unbalanced jack for instrument, line or speaker level signals.
OUTPUT:Transformer balanced XLR jack.
POWER IN: For use with the included Bellari power supply.The screw
terminal to the left of the jack may be used to secure the power cord.
CHANNEL TWO
INPUT
OUTPUT
SERIAL NUMBER
MADE IN U.S.A
INPUT
OUTPUT
12VAC
300 MA
MODEL ADB3
CHANNEL ONE
CORPORATION
OPERATION
Connect the ADB3b INPUT to the output of your instrument or line level
device.Connect the OUTPUT to a mixing board, snake, or recorder.
Start with the PAD control at full (O dB). Set the GAIN control for -20 dB
and lower the PAD control for a proper level when using a speaker or hot
line level signal.Set the GAIN control for +20 and adjust the PAD control
to use the ADB3b as a preamp/DI.
-00 dB 0
PWR
INPUTGNDLIFTGAIN
INPUT GNDLIFT GAIN
GND
LIFT +20dB
-20dB
ADB3b
CHANNEL ONE CHANNEL TWO
StereoTube
D irect B ox
INPUTPAD INPUTPAD
-00 dB 0
GND
LIFT
+20dB
-20dB
SAMPLE APPLICATIONS
12345678
REWIND FAST FWD STOP PLAY RECORD EJECT
- 00 dB 0
PWR
INPUT
GND LIFT
GAIN
INPUT GND LIFT GAIN
GND
LIFT +20 dB
-20 dB
ADB3b
CHANNEL ONE CHANNEL TWO
S tereo T u be
DirectBox
INPUT PAD INPUT PAD
- 00 dB 0
GND
LIFT
+20 dB
-20 dB
Use the ADB3b as a DI/
PREAMP between instruments
and a mixing board for live or
recording applications as shown
above.Or, use the ADB3b to
warm up tracks during mixdown
of digital recordings as shown to
the right.