Toa MX-101 Operating Instructions Manual

POWERED MIXER

Model MX-101

Operating instruction Manual

Toa Electric Co., Ltd.

KOBE, JAPAN

Contents

Precautions ................................................. 1

General Description ......................................... 2

Features.................................................... 2

Front Panel (Names of components & their usage) ............... 3

Rear Panel (Names of components & their usage) ................ 4

Connection Examples ........................................ 5

Input Connections ........................................... 6

Block and Level Diagrams .................................... 7

Specifications............................................... 8

Characteristics Diagrams ..................................... 9

Appearance................................................. 9

Precautions

1. XLR Type Audio Connector

The connectors are wired as follows.
The pin 1 is ground (shield), the pin 2 cold (low, minus), the pin 3 hot
(high,plus).

2. Description of components and functions on the MX-101.

Various descriptions are applied, depending on each manufacturer. In our
Operating and Instruction Manual explanation of components and func-

tions is made according to our usage for them.

— 1 —

General Description

The TOA MX-101 is a very compact, four channel self-powered mixer. It was

designed to deliver maximum features and performance in a cost-effective

portable PA package.

The MX-101 features four input channels, one main system output, and one

personal monitoring (foldback) output. The internal amplifier is rated at 57 watts

RMS into an 8 ohm load, and 75 watts into 4 ohms.

Each input channel has an electronically balanced XLR connector, and a
high-impedance unbalanced 1/4" phone jack. In addition, each channel features
an EQ control and a post-EQ reverb level control (send).

The master control section features a 3-band equalizer, a high-quality 2 spring

reverb, RCA tape inputs, and master volume controls for System level, Foldback,
and Reverb return to both.

The power amp features protection circuitry and autocomp compressor, both with

indicator LED's.

Features

1. Four input channels

2. 57 watts into 8 ohms, 75 watts into 4 ohms

3. 3-band EQ

4. Auto Comp compression unit w/LED

5. Built-in spring reverb

6. Power amp protection circuitry w/LED

7. System output jack

8. Tape input w/level control, RCA jacks

9. Reverb level to System

10. Foldback level control

Each Channel

1. Input level control

2. EQ control

3. Post-EQ Reverb send

4. Low-Z electronically balanced XLR input

5. Hi-Z unbalanced 1/4" input

— 2 —

Front Panel

Reverb Control

This control determines the
level of signal assigned to the
reverb mixing buss. Rotating
the control clockwise increase
the amount of reverb in that

(REV)

channel.

Input Level Control

The level control provides con­tinuously variable adjustment

of the channel output to the

program mixing buss, thus de-

termining the level of that chan-

nel in the main sound system
mix. Since the reverb signal is

"post" this control, an increase

in the level of the channel's

output will also result in a

corresponding increase in the

(LEVEL)

reverb effect of that channel.
The nominal level of the input
level control is at the "10" posi­tion.

High Equalizer Control
(HIGH)

The high EQ control alters the

high frequency response, pro-

viding ±13dB at 5kHz, and

±15dB at 15kHz of continuous-

ly variable active shelving

equalization. The "0" detented

position provides flat audio re­sponse.

Middle Equalizer Control
(MID)

The mid EQ control provided

±15dB of continuously variable
active peaking equalization at
2kHz, and has a flat audio re-

sponse when set to the "0"
detented position.

Low Equalizer Control

(LOW)

The low EQ control provides

±13dB at 100Hz, and ±15dB at

50Hz of continuously variable
active shelving equalization.

The "0" detented position pro-

vides flat audio response.

Tape Level Control
(TAPE)

This control sets the overall
level of the Tape input signal.

Reverb Control

(REV)

This control adjusts the amount
of reverb signal that is returned
to the program buss and thus
the level of reverb contained in

the main sound system.

Foldback Master Control (FB)

The FB master control adjusts
the overall combined signal
level of the four independent
channel level controls, and thus
the level of the entire on-stage
monitor mix.

System Level Control

(SYSTEM LEVEL)

The System level (PGM) control
adjusts the overall combined
signal level of the fou r indepen­dent channel level controls, and
thus the level of the main sound
system.

EQ Control

(EQ)

Rotating the control clockwise

decreases the low frequency

signal, and rotating the control
counter clockwise decreases
the high frequency signal. The
center position provides flat au-

dio response.

High Impedance Connectors
(HIGH Z)

These connectors are unba­lanced, standard 1/4" phone

jacks with an input impedance

of 100k o hms, and an input
level of -35dB. When a plug is
inserted into the high-Z input,

the coresponding XLR connec­tor is automatically switched
out of the input circuitry.

Low Impedance Connectors

(LOW

The XLR connectors are low
impedance, electronically ba-

lanced inputs with an input

Z)

impedance of 1k ohms.

Tape Input Jacks

These RCA pin jacks are wired

in parallel, with an input level
of -10dB.

Power Amp Compression In-

dicator
(COMP)

The comp LED lights when the
internal compressor is acti-

vated. The compressor is pro-

vided to protect speaker sys-

tems by compressing the input

signal level of the power ampli-

(TAPE)

fier when clipping occurs in the
output stage. Frequent flashing
of the LED is not reason for
alarm. However a constant or

steady light indicates that the
MX-101 is being over-driven
and that the internal power
amplifier is possibly "under po­wered" for that application. The
output level of the MX-101
should be decreased until the
LED only flashes intermittently.

Power Indicator LED

(POWER)

The indicator LED lights when

the power switch is "on".

Power Amp Protection Indica­tor

(PROTECT)

The indicator LED lights if the

power amplifier output is

shorted, if the temperature of

the unit rises above acceptable

levels, or if DC is drifted to the
speaker output. If the LED

should light, speaker wiring

and ambient temperature of the

MX-101 should be checked. If

the LED remains lighted, the

unit should be referred to qual­ified service personnel for re­pair.

Note:

The MX-101 protection circuit­ry will (1) detect 'faulty condi­tions' within the power ampli­fier, (2) give a visual indication,

and (3) automatically shut

down until the fault condition

is alleviated. This special cir-

cuitry ensures maximum re-

liability and virtually elimin­ates equipment damage due to
unsafe or fault conditions.
Please refer to fault protection
table on page 4 for fu ll explana­tion of this important feature.

— 3 —

Rear Panel

Speaker Jacks

The speaker outputs are stan­dard 1/4" phone jacks wired in
parallel. Speaker cables (recom-

mend at least #18 gauge wire)

should be connected between
the MX-101 and the speaker

(SPEAKERS)

systems prior to applying pow-

er to the unit.

Caution - The MX-101 should

never be operated into less than

a 4 ohms speaker load.

Power Switch

(POWER)

The power switch is a three­position type with the middle

position being the "off" posi-

tion. The MX-101 should be

operated in the switch position
which produces the lowest

amount of system hum.

AC Power Cord

The power cord is the three­wire type with proper ground-

ing facilities.

Caution - The ground pin

should not be removed under

any circumstances. If the MX­101 must be used without prop-

er grounding facilities, a suit-

able grounding adapter should

be utilized.

Operation of the MX-101 with
proper grounding techniques
will result in less system noise
and greatly reduced shock
hazard.

System Output Jack

(SYSTEM OUT)

The System Out jack is pro-

vided for connection to external

equalizers and / or power amps.

Nominal output level is +4dB

with an impedance of 600

ohms.

Earth Terminal (G ND)

AC Fuse

Foldback Output Jack

(FB

OUT)

This jack is for connection to

external power amplifiers and /

or equalizers for the on-stage

monitoring system. Nominal

output level is +4dB with an
impedance of 600 ohm.

Caution:

To insure maximum cooling of

the MX-101, adequate clearance
should be maintained between
the rear panel and any other
surface ( 4 - 6 inches should do).

The vents on the bottom and

top of th e MX-101 are also

provided for convection cool­ing. These vents should be kept

clear and open. Failure to do so

may cause thermal shut-down
of the unit.

Warning

To avoid possible equipment

damage and / or personnel in-

jury, the fuse should always be
replaced with same type and

rating. Using improper fuses

will also void the warranty. The
MX-101 should always be dis-

connected from AC outlet prior

to changing fuses. If fuses repe­atedly fails, the unit should be

referred to qualified service per-

sonnel for repair.

Fault

Excessive current due to

overloads.

Short circuits

(less than 0.4-ohm)

Temperature rise of heat
sink

(more than 105°C)

DC drift

Protection

Current limiter activates

at less than 2 ohm.

Current limiter activates
input signal is lowered,
unit shuts down.

Input signal is lowered.
Unit shuts down

Input signal is lowered.
Unit shuts down

Fault Protection Table

Indication

Compressor
LED

illuminates

Amp protection
LED

illuminates.

Amp protection
LED

illuminates.

Amp protection

LED

illuminates.

— 4 —

Action

Remove excessive loads
Minimum speaker loads
4

ohm.

Check speaker
lines/systems for shorts.

Check for adequate

ventilation.

Refer to qualified service

personnel

Restoration

Automatic restoration

after normal loads are

obtained.

Turn off power switch.

Turn on into operational

loads.

Automatic restoration

after temperature

lowers (to 75° - 95° C)

Automatic restoration

after normal bias is

regained

Connection Examples

SPEAKER SYSTEM (Self powered speakers)

for foldback

From FB OUT Jack
on Rear Panel

MAIN SPEAKER SYSTEM

From Speaker Jack

on Real Panel

Low Z input should be connected

with low impedance (50 ohm ~ 600 ohm)

microphones

Line Out

KEYBOARD

CASSETTE TAPE DECK

for playback

Line Out

MUSICAL INSTRUMENT

— 5 —

Input Connections

Generally speaking, there are two rules to follow when connecting equipment
outputs to the inputs of other equipment.

1. Properly match the impedances of the outputs and inputs.

2. Connect low impedance outputs to high impedance inputs.

It goes without saying that not only input and output impedance matching, but
also level matching should be taken into consideration. Each input channel of the
MX-101 is provided with an Input Level Control that includes a negative feedback
(NF) circuitry, so the usable signal level range is wide. Input impedances and
levels are shown in the following table.

INPUT SPECIFICATIONS

CONNECTION

CH1

CH4

TAPE

* Sensitivity is the level required to produce a program out level of +4dB.
*0dB is referenced to 0.775V RMS.

All XLR Type connectors are electronic balanced. Phone jack is unbalanced.

If the line going from one piece of equipment to another is long (more than 5m),
we recommend that balanced outputs be connected to balanced inputs.

INPUT

LOW Z

HIGH Z

ACTUAL
LOAD
IMPEDANCE

OPEN

FOR USE

WITH

NOMINAL

MICRO­PHONES

OR

LOWER IMP
LINES

OR

LOWER IMP.
LINES

SENSITIVITY*
(PGM

OUTPUT

LEVEL +4dB)

-60dB(0.78mV)

-35dB(13.8mV)

-10dB(245mV)

CONNECTOR

XLR TYPE
NC3FPP

PHONE JACK

RCA PIN JACK

As is described in the beginning of the Operating Instructions Manual, the
connectors of the MX-101 are wired as follows: Pin 1 is ground (shield). Pin 2 is
cold (low, minus). Pin 3 is hot (high, plus)

— 6 —

Block and Level Diagrams

BLOCK DIAGRAMS

LEVEL DIAGRAM

— 7 —

Specifications

MIXER SECTION

Frequency Response

+ 1, -3dB 30Hz~20kHz (input LEVEL at "5" position)

Total Harmonic Distortion

0.05% +4dB* at 1kHz.

Hum and Noise (Open)

Equivalent Input Noise

Equivalent Input Noise
All level Controls Minimum

SYSTEM Master at MAX and all

input level controls minimum

SYSTEM Master at MAX and one

input level control at Max

CONNECTION

CH1

CH4

INPUT

LOW Z

HIGH Z

-132dB* (20Hz~
20kHz)

-134dB* (IHFA)

-105dB* (IHFA)

-87dB* (IHFA)

-70dB* (IHFA)

INPUT SPECIFICATIONS

ACTUAL
LOAD
IMPEDANCE

OPEN

FOR USE

WITH
NOMINAL

MICRO­PHONES

OR

LOWER IMP
LINES

Maximum Voltage Gain

INPUT to SYSTEM out
INPUT to FB out
TAPE to SYSTEM out

Equalization

50Hz ±15dB Shelving
2kHz ±15dB Peaking
15kHz ±15dB Shelving

SENSITIVITY*
(PGM

OUTPUT

LEVEL +4dB)

-60dB(0.78mV)

-35dB(13.8mV)

64dB
64dB

14dB

CONNECTOR

XLR TYPE

PHONE JACK

TAPE

ACTUAL

CONNECTION

SYSTEM

SOURCE
IMPEDANCE

FB

POWER AMPLIFIER SECTION

Frequency Response

+ 0 -1d B 15Hz to 30kHz (75 W RMS )

Rated Power & Load

75W RMS 57W RMS

Power Output at Clipping

1%

THD. 1kHz

80W RMS 60W RMS

Total Harmonic Distortion

Less than 0.1% (100mW~75W RMS. 20Hz~20kHz.
Typically below 0.05%

Compresser Dynamic Range

Greater than 26dB

Hum and Noise

At least 100dB S/N ratio. 20Hz~20kHz
At least 108dB S/N ratio IHF-A weighted

FOR USE WITH
NOMINAL

IMP LINES

IMP LINES

OR

LOWER IMP
LINES

OUTPUT SPECIFICATIONS

NOMINAL

OR HIGHER

OR HIGHER

+4dB(1.23V)

+4dB(1.23V)

Damping Factor

200

Output Connector

Phone Jack × 2

Power Requirement

182 W

Dimensions

460(W) × 171(H) × 248(D) (18.11 × 6.73 × 8.91) ins.

Weight

7.5 Kg

*0dB is referenced to 0.775V RMS.

*Specifications are subject to change without notice.

-10dB(245mV)

OUTPUT LEVEL*

MAX BEFORE
CLIP

+ 20dB(7.75V)

+ 20dB(7.75V)

(1kHz

(16.5 Ibs)

RCA PIN JACK

CONNECTOR

PHONE JACK

PHONE JACK

— 8 —

Characteristics Diagrams

HIGH Z IN. & INPUT EQ

POWER AMP POWER BAND WIDTH

3 BAND EQ

POWER AMP T.H.D. vs POWER OUTPUT

POWER AMP COMPRESSOR

Appearance

REVERBERATION FREQUENCY RESPONSE

— 9 —

Toa Electric Co., Ltd.

KOBE, JAPAN

Printed in Japan

133-02-884-9