Toa Electronics P-912MK2, P-912MK2 UL User Manual

	Operating Instructions
TOA 900 SERIES II	P-906MK2
POWER AMPLIFIER	P-912MK2
	P-924MK2

P-906MK2

P-912MK2

P-924MK2

TO REDUCE THE RISK OF ELECTRICAL SHOCK, DO NOT REMOVE COVER.

NO USER SERVICEABLE PARTS INSIDE. REFER SERVICING TO QUALIFIED SERVICE PERSONNEL.

THE LIGHTNING FLASH WITH ARROWHEAD WITHIN A TRIANGLE IS INTENDED TO TELL THE USER THAT PARTS INSIDE THE PRODUCT ARE A RISK OF ELECTRIC SHOCK TO PERSONS.

THE EXCLAMATION POINT WITHIN A TRIANGLE IS INTENDED TO TELL THE USER THAT IMPORTANT OPERATING AND SERVICING INSTRUCTIONS ARE IN THE PAPERS WITH THE APPLIANCE.

Please follow the instructions in this manual to obtain the optimum results from this unit. We also recommend that you keep this manual handy for future reference.

TOA Corporation

Contents

General description	2
Features	2
Nomenclature
Front panel	3
Rear panel	4
Input connections	5
Output connections	6
Rack mounting	7
Operation	8
Volume adjustment	8
Installation	8
Servicing	8
Specifications	9
Appearance (P-906MK2/P-912MK2)	10
Appearance (P-924MK2)	11

General Description

The TOA P-906MK2, P-912MK2 and P-924MK2 Power Amplifiers deliver up to 60 watts, 120 watts and 240 watts of power respectively at less than 0.5% total harmonic distortion (THD) from 20 to 20,000 Hz

(transformerless 4-ohm output). The power amplifiers have a high-impedance direct input and an input port

(edge connector) to accept one plug-in module. Module selection is determined by application among the

TOA plug-in modules.

The power amplifiers have a low-cut switch for a cutoff frequency of 60 Hz, and an input-level switch for input sensitivity of 1V (0 dBV) or 100mV (–20 dBV). Output terminals provide connections for 4-ohm and 8-ohm speakers, plus 25-volt and 70-volt speaker distribution outlets. With plug-in modules, the power amplifiers may be used as a PA amplifier.

The power amplifiers can be rack mounted by using optional rack mounting bracket MB-25B(P-906MK2,

P-912MK2) and MB-35B(P-924MK2). The optional perforated panel PF-511 provides suitable ventilation, finished in color to match the power amplifiers.

Features

1.Wide frequency response : 20 ~ 20,000 Hz ± 1 dB

2.Low distortion and noise level

3.Excellent output regulation

4.A full range of plug-in modules

5.Self-protecting circuitry design

6.Varied output impedances : 4 ohms, 8 ohms, 25 and 70 volts

7.Input level switch (selectable 1000 mV/100 mV)

8.Portable or rack mounting type

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Nomenclature

Front Panel

P-906MK2, P-912MK2

P-924MK2

Power Switch	Peak Indicator LED
Applies line power. Two-position push button	Red LED lights when amplifier approaches
switch for on/off modes.	clipping level. If steady lit, the input level control
Power Indicator LED	should be turned down until the LED flashes.
Green LED lights when the power is switched	Protection Indicator LED
"ON".	Remains lit for about 5 seconds after power
Signal Indicator LED	switch is turned ON.
Green LED lights when more than -30 dB signal	Master Volume Control
level is fed to the inputs by means of the master	Adjust gain of input.
volume control.
Normal Indicator LED
Yellow LED lights when fed to the proper signal
level.

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Rear Panel

P-906MK2, P-912MK2

P-924MK2

AC Power Cord

Connects to power source.

AC Outlet (Unswitched)

Provides AC power for auxiliary equipment with power consumption of up to 500W.

Impedance Select Switch

Selects the desired impedance.

Enables unbalanced output of low impedance when this switch is set to "DIRECT".

Output terminals

Connect to speakers.

Module Input Port

Accepts optional PLUG-IN MODULES.

Application determines type of module.

For details, refer to Plug-in Module Instruction

Manual.

Low-Cut Switch

Cut off unnecessary low frequency.

Input Level Switch

Selects input sensitivity. Place in "1V" (0 dBV)

position when normally used as a power amplifier.

Note: The position of INPUT-LEVEL SWITCH should be changed according to modules used or equipment connected to DIRECT

INPUT TERMINAL.

Direct Input Terminal

Connects directly to external equipment without

using modules. Unbalanced 10k ohms.

AC Fuse (250V, 7A)

DC Fuse	(250V, 8A)
DC Fuse	(250V, 8A)

Protects amplifier from excessive current drain.

Replace only with same type fuse.

Refer to qualified service personnel if fuse blows

repeatedly.

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