Rolls MP105 ROUND SOUND User manual

MP105
ROUND SOUND
Tube Mic Preamp
INPUT OUTPUT
GAIN LEVEL
REV PHAN
PAD
NORM PWR
CLIPPHAN
12VAC
+17 +75 -∞dB 0
OWNERS MANUAL
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 accompanied 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 manufac-
ture.
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
MERCHANTABILITY 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, INCI-
DENTAL 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.
Salt Lake City, UT
www.bellari.com
4/00

1 6
INTRODUCTION
Thank you for your purchase of the Bellari MP105 Round Sound Tube Mic
Preamp.We are confident that this device will provide years of warm-sound-
ing, clear and clean microphone amplification.
Please take a moment and read this manual carefully as it provides all the
important information you need to operate this unit properly.
TABLE OF CONTENTS
Introduction 1
Table of Contents 1
Inspection 1
Description
Top Panel 2
Rear Panel 3
Connection 3
Operation 3, 4, 5
Specifications 6
Warranty Rear Cover
INSPECTION
1.Unpack and inspect the MP105 box and package.
Your MP105 was carefully packed at the factory in a protective carton.None-
theless, be sure to examine the unit and the carton for any signs of damage
that may have occurred during shipping. If obvious physical damage is
noticed, contact the carrier immediately to make a damage claim.We suggest
saving the shipping carton and packing materials for safely transporting the
unit in the future.
2.Please complete the Warranty Registration Card and return it to the factory.
FEATURES
• XLR balanced and 1/4” unbalanced inputs and outputs
• 20 dB Normal and Padded operation
• 48Volt Phantom Power
• Clip LED Indication
• Phase Reversal
SPECIFICATIONS
InputImpedance: XLR:600 Ω, 100 K ΩPadded
1/4”: 10 K Ω
Output Impdance: 50 Ω
THD: .15%
S/N Ratio: >88 dB
Maximum Input Level: +12 dB XLR, +18 dB 1/4”
Maximum Output Level: +16 dB XLR, +10 dB 1/4”
Pad: - 37 dB
Frequency Response: 20H - 25kHz +/-3 dB

25
DESCRIPTION
TOP PANEL
NORM/PAD:When this switch is OUT, the input signal is decreased by 37dB,
when IN the signal is unaffected.
PHAN:When this switch is pressed IN, 48 volts of microphone phantom
power is applied to the XLR Input jack.
REV:When this switch is pressed in, the phase of the XLR Output signal is
reversed 180 degrees.
PHAN LED:Indicates the PHAN switch is in and phantom power is being
applied to the XLR Input jack.
CLIP LED:Indicates that the internal signal is 3 dB before actual clipping.If
this LED lights continuously, possible unwanted distortion may occur.
PWR LED:Indicates the MP105 is receiving power.
GAIN CONTROL:Adjusts the amount of gain or drive in the MP105 tube
circuitry.
LEVEL CONTROL:Adjusts the amount of output volume.
OPERATION CONT.
mixer.Set the MP105 LEVEL control fully counterclockwise to begin with.Set
the GAIN control normally, then slowly bring up the LEVEL control to avoid
overdriving the next device.
- If the MP105 is used as an instrument preamp, connect the 1/4”output to
your amplifier and set the levels as desired.
NOTE:
The MP105 Round Sound is designed to clip the tube before the output
section actually distorts.This affords you the ability to drive the tube harder
providing a warmer, more natural sound.
INPUT OUTPUT
GAIN LEVEL
REV PHAN
PAD
NORM
PWR
CLIPPHAN
12VAC
+17 +75 -
∞
dB 0

3 4
REAR PANEL
INPUT:1/4”TS unbalanced and XLR balanced input jacks.
OUTPUT:1/4”TS unbalanced and XLR balanced input jacks.
12VAC:Connects to the supplied Rolls/Bellari PS12 12 volt AC adapter.
CONNECTION
First, make sure the MP105 power supply is connected to an AC outlet.
Connect the microphone to the MP105 input jack, press in the PHAN switch if
the microphone is a condenser type and requires phantom power. Connect
the MP105 Output to the Input of a digital recorder or mixer via either the XLR
or 1/4”jack.
OPERATION
The MP105 amplifies your microphone signal to a professional line level.That
signal may then be sent to a digital recorder, mixing console, or signal proces-
sor.Shown in Fig. 1 is an example of how to connect a microphone to the
MP105, and then to the input of a recorder or mixer.
- If you connect the MP105 XLR Output jack to an XLR input on a mixer, you
may be using the mixer channel’s mic preamps.This may result in distortion.If
this happens, use the MP105 1/4”Output to a 1/4” line input on the mixer.
MIXER OR DIGITAL RECORDER
INPUT OUTPUT
GAIN LEVEL
REV PHAN
PAD
NORM PWR
CLIPPHAN
12VAC
+17 +75
-
∞
dB 0
Speak or sing into the microphone at the volume level used during perfor-
mance.Set the GAIN control so the CLIP LED lights occasionally - only
during the extremely loud parts. Adjust the MP105 output LEVEL control so
the input level indicators on the recorder or mixer show a desirable amount.
If your microphone puts out a high level of power, or if you are connecting a
balanced line-level signal to the MP105, try setting the NORM/PAD switch to
the out or PAD position.
The Phase Reverse (REV) switch is used to change the phase of the output
signal 180 degrees from that of the input.This is for correcting possible wiring
mismatches, or microphone phase mismatches.
INSTRUMENT PREAMP
The MP105 may be used as an instrument preamp or direct box. Connect
your instrument to the 1/4”unbalanced input.
- If using the MP105 as a direct box, use the XLR output and connect to the
INPUTS
OUTPUTS
12VAC
Fig. 1