Radio Shack MPA-125 - User Manual

Owner’s Manual Please read before using this equipment.
MPA-125 100-Watt PA Amplifier
32-2003.fm Page 1 Tuesday, March 28, 2000 10:45 AM

Radio Shack MPA-125 Specifications

General

Input Impedance	50k ohms
Dimensions	17.3" x 5.1" x 13.8" (W x H x D)
Weight	24.3 lbs
Frequency Response	20Hz - 20kHz
Total Harmonic Distortion	Less than 0.1% at rated power
Inputs	RCA
Outputs	Speakers
Input Sensitivity	1V for full output

Summary

Features

Amplifier Power and Performance Features

Covers 100W output, frequency response, and VU meter.

Mounting and Indicator Features

Discusses mounting options, clipping, and overload indicators.

Control Features

Details Master Volume, EQ switch, mixing controls, and feedback filter.

Input and Output Connectivity

Describes microphone, CD/Aux, and headphone connection types.

Preparation and Control Setup

Presetting Input Devices and Amplifier Controls

Guides on setting initial levels for optimal use.

Amplifier Connections

Mounting and Speaker Placement Guidance

Instructions for amplifier installation and speaker positioning.

Connecting Audio Input Sources

How to connect microphones, turntables, CD players, etc.

Connecting Microphones

How to connect up to four microphones using balanced or unbalanced jacks.

Connecting a Turntable

Connecting Auxiliary and MIX BUS Sources

Connecting an Equalizer

Speaker Connection Guide

Determining Total Speaker Impedance

Explains how to calculate impedance for speaker configurations.

Phasing and Speaker Wire Requirements

Importance of correct speaker phasing and wire gauge selection.

Speaker Wire Preparation and Single Speaker Connection

Connecting Two Speakers in Series

Connecting Speakers in Parallel and Series;Parallel

Connecting Speakers with Transformers

Power Connection and Initial Amplifier Use

Using Your MPA-125 Amplifier

Setting Input Levels and Master Volume

Guides on adjusting source volumes and the master volume.

Utilizing the Feedback Filter

Instructions for reducing audio feedback using the filter.

Safety and Monitoring Features

Understanding Safety Indicators

Explains clipping and protection indicators on the amplifier.

Audio Monitoring and Safe Listening Practices

Using headphones and maintaining safe volume levels.

Equalizer Integration

Connecting and configuring an external equalizer.

Advanced Feedback Control

Troubleshooting Common Issues

Resolving Power and Sound Problems

Solutions for amplifiers with no power or no sound.

Addressing Feedback and Speaker Impedance

Fixing feedback and ensuring correct speaker impedance.

Amplifier Care and Maintenance

Environmental Protection and Handling

Keeping the amplifier safe from elements and damage.

Cleaning and Warranty Warnings

Proper cleaning methods and warnings about warranty voiding.

Fuse Replacement Procedure

FCC Interference Notice

MPA-125 Technical Specifications

Limited One-Year Product Warranty