Rocktron PC Preamp GIS User Manual

GUITAR INTERFACE SYSTEM

User's Manual

May be covered by one or more of the following: U.S. Patents #4538297, 4647876, 4696044, 4745309,
4881047, 4893099, 5124657, 5263091, 5268527, 5319713, 5333201, 5402498 and 5493617. Other patents
pending. Foreign patents pending.

Contents

Introduction----------------------------------------------- 1
Front Panel------------------------------------------------ 2
Rear Panel------------------------------------------------- 4
Placement ------------------------------------------------- 5
Connections ---------------------------------------------- 6

Guitar applications ------------------------------------------------------------ 6
Using auxiliary input signals ----------------------------------------------- 7
Mixing applications ----------------------------------------------------------- 8

Block Diagram ------------------------------------------- 9
Operation ------------------------------------------------ 10

About HUSH noise Reduction------------------------------------------- 10

Dynamic Filtering ---------------------------------------------- 10
Downward Expansion-----------------------------------------11

About the Analog Devices SSM2000... ------------------------------- 12

Specifications ------------------------------------------ 13

Introduction

Thank you for purchasing the new Rocktron GIS PC Preamp  the

world's first guitar/vocal processor designed to interface directly to your

computer.

The GIS PC Preamp turns the computer into a virtual guitar amp

system with clean/distortion tones along with a 3-band EQ. Connection

of your CD or tape player to AUX input makes playing or singing along

with your favorite tunes extremely easy. Record them right to the PC

using any wave recording software.

The GIS PC Preamp is designed to take up as little workspace as

possible  place it under the monitor or mount it to the side of your

tower.

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Front Panel

1 ¼" phone INPUT jack

This ¼" standard phone jack provides an input to the GIS PC Preamp.

2 GAIN control

This control determines the amount of gain applied to the signal in the

distortion mode.

3 BASS control

This control determines the amount of bass in both clean and distortion

modes.

4 MID control

This control determines the amount of midrange in both clean and distortion

modes.

5 TREBLE control

This control determines the amount of treble in both clean and distortion

modes.

6 HUSH THRESHOLD control

In the distortion mode, this control determines the minimum input level at

which the HUSH filter and downward expander will begin to operate. This

operation is present in the distortion mode only.

In the clean mode, the internal SSM2000 HUSH circuit is configured to

operate as a compressor. Note that the HUSH THRESHOLD control is

disabled when operating the GIS PC Preamp in clean mode.

7 OUTPUT LEVEL control

This control determines the overall level of the preamp section only.

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8 CLN/DIST switch

This switch is used to select CLEAN or DISTORTION mode.

9 CLN LED

When lit, indicates that the CLEAN channel is currently active. In the clean

mode, the internal SSM2000 HUSH IC is configured to provide compression.

10 DIST LED

When lit, indicates that the DISTORTION channel is currently active. In the

distortion mode, the SSM2000 HUSH IC is configured to provide HUSH noise

reduction.

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