Operating Instruction Manual POWERED MIXER

Model MX-401

Toa Electric Co., Ltd. KOBE, JAPAN Contents

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-401. Various descriptions are applied, depending on each manufacturer. In our Operating and Instruction Manual explanation of components and functions is made according to our usage for them. General Description

The TOA MX-401 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-401 features four input channels, one program output, and one Foldback output. The internal is rated at 100 watts into an 8 ohm load, and 150 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 two-band EQ, a pre-EQ Foldback send, and post-EQ reverb send. The master control section features a patchable 5-band graphic equalizer, a quality 3- spring reverb, a full patch bay with 1/4" phone auxiliary and RCA tape inputs, and master volume controls for Program, Foldback, and Reverb return to both. The power amp protection circuitry and autocomp compressor, both with LED's, are also located in this section.

Features

1. Four input channels

2. 100 watts into 8 ohms, 150 watts into 4 ohms

3. Patchable 5-band graphic EQ

4. Auto Comp compression unit w/LED

5. Built-in spring reverb

6. Power amp protection circuitry w/LED

7. Full patch bay

8. Aux input w/level control, RCA jacks and parallel phone 1/4" jacks.

9. Reverb level to PGM and FB

10. Independent Foldback mix.

Each Channel 1. Input level control

2. Two band EQ

3. Pre-EQ Foldback send

5. Low-Z electronically balanced XLR input

6. Hi-Z unbalanced 1/4" input

— 2— Front Panel

Reverb to Foldback Graphic Equalizer Power Amp Compression Control (REV TO FB) () Indicator High Equalizer Control This control adjusts the amount The graphic equalizer is 5 inde- (COMP) (HIGH) of reverb signal that is returned pendent active bands (filters), The Comp LED lights when the The high EQ control alters the to the foldback buss and thus the providing 12dB of boost or cut at internal compressor is activated. high frequency response of the level of reverb contained in the each center frequency. The "0" The compressor is provided to input channel, providing ±13dB on-stage monitor mix. detented position provides flat protect speaker systems by com- at 10kHz, and ±15dB at 20kHz of audio response. pressing the input signal level of continuously variable active Reverb/Control the power amplifier when clip- shelving equalization. The "0" ping occurs in the output stage. detented position provides flat (REV) Foldback Master Control (FB) This control determines the Frequent flashing of the LED is audio response. The FB master control adjusts not reason for alarm. However, a level of signal assigned to the re- the overall combined signal level verb mixing buss. Rotating the constant or steady light indicates of the four independent channel that the MX-401 is being over- control clockwise increases the foldback sends, and thus the Low Equalizer Control amount of reverb in that channel. driven and that the internal level of the entire on-stage moni- power amplifier is possibly (LOW) tor mix. The low EQ control provides Foldback Control (FB) "under powered" for that applica- ±13dB at 100Hz and ±15dB at tion. The output level of the MX- The Foldback control deter- Aux Level Control (AUX) 50Hz of continuously variable mines the level of signal assign- 401 should be decreased until the This control sets the overall level LED only flashes intermittently. active shelving equalization. ed to the foldback mixing buss, of the Aux input signal. The "0" detented position pro- thus setting the level of that vides flat audio response. channel in the on-stage monitor Power Indicator LED mix. (POWER) The indicator LED lights when the power switch is "on".

Power Amp Protection Indicator (PROTECT) The indicator LED lights if the Input Level Control Reverb to Program Control power amplifier output is short- (LEVEL) (REV TO PGM) Program Output Jack ed, if the temperature of the unit The level control provides con- This control adjusts the amount (PGM OUT) rises above acceptable levels, or tinuously variable adjustment of reverb signal that is returned The PGM Out jack is provided if DC is drifted to the speaker of the channel output to the to the program buss and thus the for connection to external equal- outputs. If the LED should light, program mixing buss, thus level of reverb contained in the izers and/or power amps, deriv- speaker wiring and ambient determining the level of that main sound system. ing its signal prior to the internal temperature of the MX-401 channel in the main sound GEQ and power amp. Nominal should be checked. If the LED system mix. Since the reverb Program Master Control output level is +4dB with an remains lighted, the unit should signal is "post" this control, an (PGM) impedance of 600 ohms. be referred to qualified service increase in the level of the The PGM control adjusts the personnel for repair. channel's output will also result overall combined signal level of Graphic Equalizer Input Jack Note: in a corresponding increase in the four independent channel (GEQ IN) The MX-401 protection circuitry the of that channel. level controls, and thus the level The GEQ input jack allows the will (1) detect 'faulty conditions' The nominal level of the input of the main sound system. graphic equalizer to be used in- within the power amplifier, (2) level control is at the "10" posi- dependently of the MX-401 with give a visual indication, and (3) tion. Aux Input Jacks other external equipment, or the automatically shut down until (AUX IN) internal power amplifier and the the fault condition is alleviated. High Impedance Connectors The phone jack and RCA pin graphic equalizer with external This special circuitry ensures (HIGH Z) jacks are wired in parallel, with equipment. When a plug is maximum reliability and vir- These connectors are unbal- an input level of —20dB. When a inserted, the main mix from tually eliminates equipment anced, standard 1/4" phone jacks plug is inserted into the phone the program buss is disconnected damage due to unsafe or fault with an input impedance of 27k jack, the RCA pin jacks are from the graphic equalizer and conditions. Please refer to fault ohms, and an input level of automatically switched out of the power amplifier. The nomi- protection table on page 4 for —35dB. When a plug is inserted the AUX circuitry. nal input level is +4dB with an full explanation of this im- into the high -Z input, the cor- input impedance of 50k ohms. portant feature. responding XLR connector is Foldback Output Jack automatically switched out of the (FB OUT) input circuitry. This jack is for connection to Graphic Equalizer Output Jack Power Amplifier Input Jack external power and/ (GEQ OUT) (PWR IN) Low Impedance Connectors or equalizers for the on-stage This jack allows the MX-401 The PWR Amp input jack allows (LOW Z) monitoring system. Nominal and the internal graphic equal- the internal power amplifier to The XLR connectors are low im- output level is +4dB with an izer to be used with an external be used with external equip- pedance, electronically balanced impedance of 600 ohms. If the power amplifier, or in conjunc- ment. When a plug is inserted, inputs with an input impedance internal power amp and equal- tion with the GEQ in jack, to be the power amp is automatically of 1k ohms. izer are to be used for the on- used independently of all other disconnected from the MX-401 stage monitor system, the FB MX-401 circuitry. Nominal mixer section. The nominal in- output should be connected to output level is +4dB with an put level is +4dB with an input the GEQ input jack. impedance of 600 ohms. impedance of 10k ohms.

— 3— Rear Panel

Power Switch (POWER) Cord Wrap The power switch is a three- The cord wrap is provided for position type with the middle convenient storage of the power position being the "off position. cord when t h e MX-401 is not in The MX-401 should be operated use. in the switch position which Caution - The power cord should produces the lowest amount of always be completely removed system hum. from the cord wrap prior to operation of the unit. This will Speaker Jacks (SPEAKERS) insure maximum cooling of the The speaker outputs are stand- MX-401 For the same reason, ard 1/4" phone jacks wired in adequate clearance should be parallel. Speaker cables (recom- maintained between the rear mend at least #18 gauge wire) panel and any other surface (4-6 should be connected between inches should do). The vents on the MX-401 and the speaker the bottom and top of the MX- systems prior to applying power 401 are also provided for convec- to the unit. tion cooling. These vents should be kept clear and open. Failure to Caution - The MX-401 should do so may cause thermal shut- never be operated into less than a 4 ohm speaker load. down of the unit.

Earth Terminal (GND) Warning - To avoid possible AC Fuse equipment damage and/or per- AC Power Cord sonnel injury, the fuse should The power cord is the three-wire always be replaced with same type with proper grounding faci- type and rating. Using improper lities. fuses will also void the warran- Caution - The ground pin should Operation of the MX-401 with ty. The MX-401 should always not be removed under any cir- proper grounding techniques be disconnected from AC outlet cumstances. If the MX-401 must will result in less system noise prior to changing fuses. If fuse be used without proper ground- and greatly reduced shock repeatedly fails, the unit should ing facilities, a suitable ground- hazard. be referred to qualified service ing adapter should be utilized. personnel for repair.

Fault Protection Table

Fault Protection Indication Action Restoration

Excessive current due to Current limiter activates at Compressor Remove excessive loads. Automatic restoration overloads. less than 2 ohm. LED illuminates. Minimum speaker loads after normal loads are 4 ohm. obtained.

Short circuits Current limiter activates, Amp protection Check speaker Turn off power switch. (less than 0.4-ohm) input signal is lowered, LED illuminates. lines/systems for shorts. Turn on into operational unit shuts down. loads.

Temperature rise of heat Input signal is lowered. Amp protection Check for adequate Automatic restoration sink Unit shuts down. LED illuminates. ventilation. after temperature (more than 105°C) lowers (to 75° - 95° C)

DC drift Input signal is lowered. Amp protection Refer to qualified service Automatic restoration Unit shuts down. LED illuminates. personnel. after normal bias is regained.

— 4— Connection Examples

SPEAKER SYSTEM (Self ) MAIN SPEAKER SYSTEM for foldback

From Speaker Jack on Rear Panel

Line Out

KEYBOARD Low Z input should be connected with low impedance (50 ohm ~ 600 ohm) 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-401 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

ACTUAL FOR USE SENSITIVITY* CONNECTION INPUT LOAD WITH (PGM OUTPUT CONNECTOR IMPEDANCE NOMINAL LEVEL +4dB)

50 TO 250 CH1 LOW Z OPEN MICRO- -60dB (0.78mV) XLR TYPE NC3F PHONES 27k OR CH4 HIGH Z 27k LOWER IMP -35dB (13.8mV) PHONE JACK LINES

30k OR RCA PIN JACK AUX 30k LOWER IMP, -20dB (77.5mV) PHONE JACK LINES

50k OR GEQ 50k LOWER IMP, +4dB (1.23V) PHONE JACK LINES

10k OR PWR/AMP 10k LOWER IMP, +4dB (1.23V) PHONE JACK LINES

*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.

As is described in the beginning of the Operating Instructions Manual, the connectors of the MX-401 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 Maximum Voltage Gain Frequency Response INPUT to PGM out 64dB +0, -3dB 60Hz~20kHz (input LEVEL at "5" position) INPUT to FB out 64dB INPUT to GEQ out 64dB Total Harmonic Distortion AUX to PGM out 24dB 0.05% +4dB* at 1kHz. Input EQ Hum and Noise (Open) 50Hz ±15dB Shelving Equivalent Input Noise -130dB* (20Hz ~ 20kHz) 20kHz ±15dB Shelving Equivalent Input Noise -133dB* (IHF A) All level Controls Minimum -110dB* (IHF A) PGM Master at MAX and all Equalization input level controls minimum -90dB* (IHF A) 63Hz ±12dB Peaking 2kHz ±12dB Peaking PGM Master at MAX and one 250kHz ±12dB Peaking 8kHz ±12dB Peaking input level control at MAX -70dB* (IHF A) 1kHz ±12dB Peaking

INPUT SPECIFICATIONS

ACTUAL FOR USE SENSITIVITY* CONNECTION INPUT LOAD WITH (PGM OUTPUT CONNECTOR IMPEDANCE NOMINAL LEVEL +4dB)

50 TO 250 CH1 LOW Z OPEN MICRO- -60dB (0.78mV) XLR TYPE NC3F PHONES 27k OR CH4 HIGH Z 27k LOWER IMP -35dB (13.8mV) PHONE JACK LINES

30k OR RCA PIN JACK AUX 30k LOWER IMP, -20dB (77.5mV) PHONE JACK LINES

50k OR GEQ 50k LOWER IMP,. +4dB (1.23V) PHONE JACK LINES

10k OR PWR/AMP 10k LOWER IMP, +4dB (1.23V) PHONE JACK LINES

OUTPUT SPECIFICATIONS OUTPUT LEVEL* ACTUAL FOR USE WITH CONNECTION MAX. BEFORE CONNECTOR SOURCE NOMINAL NOMINAL IMPEDANCE CLIP 600! OR HIGHER +20dB (7.75V) PHONE JACK PGM 600 IMP. LINES +4dB (1.23V) 600 OR HIGHER 600 +4dB (1.23V) +20dB (7.75V) PHONE JACK GEQ IMP. LINES 600 OR HIGHER FB 600 +4dB (1.23V) +20dB (7.75V) PHONE JACK IMP. LINES

POWER AMPLIFIER SECTION Frequency Response Input Sensitivity +0, -1dB 15Hz to 30k Hz (150W RMS 4 +4dB* (1.23V) Rated Power & Load Input Impedance 150W RMS (4 ) 110W RMS (8 ) 10k Power Output at Clipping Output Connector 1% THD, 1kHz Phone Jack ×2 160W RMS (4 ) 115 W RMS ( ) Power Requirement Total Harmonic Distortion 300W Less than 0.1% (200mW ~150W RMS, 20Hz~20kHz, 4 ) Dimensions Typically below 0.05% 494(W) × 180(H) × 304(D) (19.44 × 7.09 × 11.97) ins. Compresser Dynamic Range Weight Greater than 26dB 10 kg (22 lbs) Hum and Noise At least 105dB S/N ratio, 20Hz~20kHz *0dB is referenced to 0.775V RMS. At least 109dB S/N ratio IHF-A weighted Damping Factor *Specifications are subject to change without notice. Greater than 200 [1kHz 8 ) Characteristics Diagrams

LOW Z HIGH Z IN & INPUT EQ (LEVEL Control) HIGH Z IN. & INPUT EQ (set at "5") GEQ

POWER AMP POWER BAND WIDTH POWER AMP T.H.D. vs POWER OUTPUT

POWER AMP COMPRESSOR REVERBERATION FREQUENCY RESPONSE

Appearance

304 (11.97") 494 (19.44") (7.09") 180

— 9 — Toa Electric Co., Ltd. KOBE, JAPAN

Printed in Japan 133-02-873-5