Rolls MA2355 User manual

MA2355
Mixer / Amplifier
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, TRANS-
PORTATION 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 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 LIABILI-
TIES, 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.
ROLLS CORPORATION
SALT LAKE CITY, UTAH
1/04
MIC ONE MIC TWO
tone tone
SOURCE
ONE SOURCE TWO SOURCE THREE
TREBLE BASS
0
RIG
H
0 10
LEFT OUTPUT
pwr clip
- + - + 0 10 0 10 0 10 0 10 0 10
0
10
G
HT OUTPUT
clip
MA2355
Mixer /
Amplifier

INTRODUCTION
Thank your for your purchase of the Rolls MA2355 Mixer / Amplifier. The MA2355
is a two rack space mixer amplifier designed for restaurants, schools, churches,
clubs etc. The unit provides a compact and efficient way to mix up to three
sources such as AM/FM tuners, CD players, and video players with up to two
microphones. Priority talkover is provided on Microphone Two for paging, and on
Source One for a jukebox, telephone, etc. The power output section may be
connected to 8, or 16 ohm speakers.
NOTE: THIS MANUAL ASSUMES THE USER HAS A WORKING KNOWLEDGE
OF AUDIO ELECTRONICS, BALANCED AND UNBALANCED CONNECTIONS,
AND PROPER SIGNAL LEVEL SETTING.
INSPECTION
1. Unpack and inspect the MA2355 box and package.
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 visit our website at www.rolls.com and click on the Register Your
Warranty Here button, or complete the Warranty Registration Card and return it to
the factory.
TABLE OF CONTENTS
Introduction 1
Inspection 1
Table of Contents 1
Description 2
Connection 3
Operation 4
Specifications 5
Schematic 6
Warranty Back Cover
SCHEMATIC
1 6

DESCRIPTION
FRONT PANEL
MIC ONE MIC TWO
tone tone
SOURCE
ONE SOURCE TWO SOURCE THREE
TREBLE BASS
0 10
RIGHT OUTPUT
0 10
LEFT OUTPUT
pwr clip clip MA2355
Mixer /
Amplifier
- + - + 0 10 0 10 0 10 0 10 0 10
Mic 1, 2: Adjust the level of signal from the corresponding Mic Input.
TONE 1, 2: Adjusts the frequency content of the microphone signal in the channel.
When the control is turned counter-clockwise, the high frequencies are cut, when
the control is turned clockwise, the low frequencies are cut.
Source 1 - 3: Adjust the volume of input from the RCA Source Inputs.
Bass: Adjusts the low frequencies of the Source 2 and 3 signals only.
Treble: Adjusts the high frequencies of the Source 2 and 3 signals only.
Left / Right Output: Adjusts that channel’s output level
Clip. LED indicating clipping in the MA2355 amplifier.
Power: LED indicating power is applied to the MA2355 and the unit is on.
REAR PANEL
321
RECORD
OUTPUT
MIC TWO MIC ONE
SOURCE 1
STEREO
MIC 2
on
STEREOMONO
SOURCE INPUTS
LEFT AMP
INSERT
RIGHT AMP
INSERT
LEFT OUTPUTRIGHT OUTPUT
WARNING:
DO NOT EXPOSETHIS EQUIPMENT TO RAIN OR MOISTURE
NO USER SERVICABLE PARTS INSIDE.
MODEL MA2355
MADE IN USA
www.rolls.com
SERIAL NUMBER
2355 -
RISQUE DE CHOC - NE PAS ENLEVER
PHANTOM POWER
PRIORITY ◗
SOURCE 1 MONO ◗
21
Right / Left Output: Spring-loaded terminal for connection to the speakers.
LEFT/RIGHT AMP INSERT: 1/4” Tip-Send, Ring-Return insert jack.
MICROPHONE ONE and TWO: Balanced XLR inputs to be connected to dynamic
or condenser microphones.
DIP SWITCH: Contains the small switches for engaging Mic 1, 2 phantom power,
Source 3 Stereo or Mono, the priority (Talk Over) functions, and the Mono/Stereo
select.
SOURCE INPUTS: Stereo RCA jacks, Channels 1 - 3, for connection to stereo
sources such as AM/FM tuners, cassette players, cd players, or video players.
RECORD OUT: Stereo RCA jacks, contains all mixed signals before the Master
Level controls.
SPECIFICATIONS
MIXER
Input Impedance: Mic: 600 Ohms XLR balanced
Source: 22K Ohms RCA
Insert: 22K Ohms 1/4" TS unbal.
Max Input Level: Mic: -14 dBV Mic level Max
Source: 24 dBV
Insert: 24 dBV
Connectors: 2: XLR, 6: Stereo RCA, 3: 1/4" TRS, 1: 1/4” TS
Phantom Power: +12 VDC
Max Gain: Mic: 60 dBV
Source: 26 dBV
Tone Controls: +/-12 dB 100 Hz Bass
+/-12 dB 11kHz Treble
Noise Floor: Speaker out: -67 dBV
Pre Out: -90 dBV
S/N Ratio: 96 dBV
Priority Attenuation: 60 dBV
POWER AMP
Recommended Load: 8 Ohms
THD + Noise: .06% typical-82 dBV
120 VAC 50-60 Hz
Weight: 5.5 lbs (2.5 kg)
Size: 19" x 1.75" x 5"
(48cm x 4.5cm x 12.7cm)
25

OPERATION
DIP SWITCH SETTINGS (From left to right)
• If a microphone requires phantom power, move the Mic channel’s corresponding
PHANTOM POWER switch to the up position. This applies 12 volts dc phantom
power to the indicated microphone.
• SOURCE 1 MONO; this switch sums the Right and Left inputs of Source 1 to
mixed dual-mono inputs.
• Mic 2 Priority; when in the up position, all program material on Mic 1 and
Sources 2 and 3 will be “ducked” or muted when a signal is present at Mic 2.
Source 1 is left un-muted.
This function is used for paging.
• Source 1 Priority: when in the up position, Source 2,and 3 will be “ducked” or
muted by the signals at Source 1.
This function is for jukebox priority. With a jukebox connected to Source input 1,
and the Talkover switch 2 on, the other Source input signals such as background
music, will be muted and only the jukebox will be heard.
• MONO / STEREO: When up, the output of the MA2355 is summed to mono.
Either jack can be used as a mono output.
FAULT PROTECTION
The fault protection in the MA2355 limits the current to the output stage. This
mode is entered whenever the output stage is called upon for too much power, it
may also be fooled by impedances lower than four ohms - which may cause the
output stage to overheat and be irreversably damaged.
Since the MA2355 is convection cooled, the unit radiates heat from the front panel
and, depending on the load demand, it may become very hot if drawn upon
heavily.
CONNECTION
Inputs
Connect low impedance microphones to the Mic inputs. If a paging microphone is
being used, connect it to Mic Input 2 so it may be used with the Talk Over function.
Connect source signals such as CD players, cassette players or video players to
the RCA Source Inputs. If a jukebox is being connected, and you want its signal to
mute the other source signals, connect it to Source input 1.
For recording purposes, connect a stereo RCA cable to the Record Out jacks, and
to your recording device.
Amp Inserts
To connect a signal processor to the MA2355 signal(s), use an insert plug, or
cable wired as shown in Fig. 1. This return signal is then sent to the output level
section of the amplifier.
Outputs
Connect speakers (we recommend loads no lower than 8 ohms) to the Outputs of
the MA2355 by pressing in each of the spring-loaded terminals and inserting the
proper wire into the proper terminal i.e.; + = red, - = black.
Connect the MA2355 to a properly grounded AC outlet.
3 4
To Amp Insert
Fig. 1