All activities within the Signal Processor Emulation module require the use of a Macintosh G3 computer (or better) and Digital Performer 2.7 (or higher) software. To conduct the following activities in their entirety, you will need to download a StuffIt archive containing sample audio files and a Quick Time movie. Clicking on the link below will begin the download process.

Important Note: The archive file is quite large. It is not recommended that you attempt to download it if you are connected to the Internet using anything less than a high-speed connection (i.e. cable modem, T-1 line, DSL, etc.) If you do not have access to a high-speed Internet connection, please send a message to the Texas Collaborative Clearinghouse to request a copy of a CD-ROM containing all files for the Signal Processor Emulation module.

Download the StuffIt Archive for Topic 2: Dynamic Range Processors
[File size: 81,948 KB Contains all files associated with Topic 2 Activities]

If you do not have StuffIt, you can download a trial version at

Download an Adobe Acrobat file titled "General Instructions for Signal Processor Emulation" used by all activities in the module.

Activity 2.1
Dynamic Range Processor Demonstration

Demonstrate the common uses of compressors and expanders

Using audio files of drum tracks, bass guitar and vocals, students will adjust compressors and expanders to hear their effect on unprocessed audio.

The demo sheet discusses common uses of signal processors and common settings for each type of musical instrument.

Materials Provided
Sound files that contain individual tracks of drums, bass, and vocals with plug-in processors pre-selected.
Download demo instruction sheet here (.doc or .pdf).

Activity 2.2
Dynamic Range Processor Drills

Identify dynamic range processor settings by ear.

Using audio files of a snare drum, bass guitar and vocals, students match the attack, release and ratio settings of compressors and expanders with predetermined ones.

Students will complete a review sheet with 10 ear-training drills designed to help students learn to hear the difference in the dynamic range settings.

Materials Provided
Individual tracks of snare drums, bass and vocals; review sheet with questions;
QuickTime movie giving the instructions aloud; and
Dynamic Processor Drills sheet (.doc or .pdf)