Alesis QuadraVerb Service Manual------ vi 08/13/04
Table of Contents
PREFACE....................................................................................................................................ii
READ THIS!.................................................................................................................................ii
WARNINGS................................................................................................................................. iii
SAFETY SUGGESTIONS........................................................................................................... iv
General Troubleshooting .............................................................................................................v
1.0 QuadraVerb General Description ..........................................................................................1
2.0 Power Supply.........................................................................................................................1
2.1 Battery Backup..........................................................................................................2
3.0 Analog Signal Paths...............................................................................................................2
3.1 Anti-Aliasing Filters ...................................................................................................3
3.2 Successive Approximation........................................................................................3
4.0 Digital Signal Paths................................................................................................................4
4.1 80C31 Micro Controller Circuit..................................................................................4
4.2 Reset.........................................................................................................................4
4.3 Memory Mapped I/O .................................................................................................5
4.4 Analog Input and the 8031........................................................................................5
4.5 DASP 24 ASIC..........................................................................................................5
5.0 Test Procedures.....................................................................................................................6
6.0 Adjustments ...........................................................................................................................6
7.0 Updates and Revisions..........................................................................................................6
7.1 D15............................................................................................................................7
7.2 Header Capacitor......................................................................................................7
7.3 R66............................................................................................................................7
7.4 SRAM Supply............................................................................................................7
7.5 Battery Ground..........................................................................................................7
7.6 Cables.......................................................................................................................7
7.5 LCD Contrast ............................................................................................................7
7.6 LCD Cable Header....................................................................................................7
7.7 Wet VCA Removal....................................................................................................7
7.8 DAC Adjustment Installation .....................................................................................8
7.9 Increasing Output Gain.............................................................................................8
7.10 QV I/P Filter Kit Installation.....................................................................................8
8.0 Helpful Hints & Common Solutions........................................................................................12
9.0 Schematics.............................................................................................................................14
10.0 Software History..........................................................................................................
.........16
11.0 Quadraverb Plus MIDI Implementation/System Exclusive ..................................................18
12.0 Quadraverb Service Parts List.............................................................................................34
Index.............................................................................................................................................37
Service Manual History................................................................................................................39