ENSONIQ DP/4 Service Manual

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2006 MusicParts.Com, Inc.
MusicParts.Com
Visit us on the web at: http://www.musicparts.com/
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Brand: Ensoniq
Model DP/4
Product: Parallel Effects Processor
Description: Diagnostics And Troubleshooting Guide
Musicparts Document Number: 51635 TechTips: No Pages: 32 Dated: 1993

ENSONIQ DP/4 Specifications

General

Type	Multi-Effects Processor
Channels	4
Number of Effects	Up to 4 simultaneous effects
Sampling Rate	44.1 kHz
Bit Depth	16-bit
A/D Resolution	16-bit
D/A Resolution	16-bit
Power Supply	Internal
Effects	Reverb, Delay, Chorus, Flanger, Pitch Shift, Distortion, EQ
MIDI	In, Out
Dynamic Range	90 dB
Frequency Response	20 Hz - 20 kHz
Power Requirements	120V AC

Summary

Essential DP/4 Operation and Safety

System Reinitialization and Reset Procedures

DP/4 Power Supply and Circuitry

Power Safety and Circuit Checks

Electrical safety, fuse inspection, and initial power supply voltage checks.

DP/4 Transformer Board Information

Transformer Board Identification and Voltages

Details on transformer board versions, voltage charts, and test points.

Transformer Secondary Board Troubleshooting

Unloaded Testing Flowchart

Flowchart for diagnosing issues with the transformer secondary board.

DP/4 Display and Event Messages

Display Self-Test and Troubleshooting

DP/4 Unexpected Event Messages

Understanding Event Messages

DP/4 Low Battery Warning Diagnosis

Low Battery Message Troubleshooting

DP/4 Audio Problem Troubleshooting

Audio Signal Troubleshooting Overview

Detailed DP/4 Audio Signal Analysis

In-depth Audio Signal Testing

DP/4 System Test Procedures

Test Setup and Reinitialization

DP/4 Analog Input and Backup Tests

CV Pedal, Footswitch, and Battery Backup Tests

DP/4 Module Replacement Guide

Main Board Replacement

Step-by-step instructions for removing and installing the main board.

DP/4 Front Panel Assembly Replacement

Front Panel Replacement Steps

Steps for removing and installing the front panel assembly.

DP/4 Transformer Secondary Board Replacement

Transformer Board Replacement Steps

Steps for replacing the transformer secondary board.

DP/4 O.S. EPROM Replacement

EPROM Replacement and Reinitialization

Procedure for replacing O.S. EPROMs and reinitializing the unit.