Downloadable Sounds - Level 1 Specification
New! Version 1.1b - September 2004
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Introduction
The Downloadable Sounds (DLS) Level 1 Specification defined the first industry-standard approach to delivering sound sets for sample-based ("wavetable") synthesizers. DLS allows composers and sound designers of CD-ROM and Internet-based content to develop custom sound sets and achieve consistent playback across a broad number of existing and pending devices. A DLS-compatible synthesizer becomes an expressive and interactive audio reproduction engine that performs exactly as the composer intended.
The combination of MIDI messages controlling small sound samples, as opposed to the use of streaming digitized audio, makes DLS especially appropriate for interactive multimedia applications, and for putting sound and music on web pages where fast downloading, seamless playback, and user interaction are critical.
The DLS Level 1 Specification describes the minimal synthesis architecture and feature set needed for a device to be capable of playing DLS-format sound samples. DLS Level 1 is aimed squarely at wavteable PC audio devices in use today, many of which can support DLS Level 1 with only minor driver (PC system) modifications. Later levels (DLS-2, etc.) address enhanced performance and features, and may include different methods of synthesis.
Document Table of Contents
CHAPTER 1: DEVICE ARCHITECTURE
- INTRODUCTION
- THE PROBLEM
- THE SOLUTION
- OBJECTIVES
- DESIGN OVERVIEW
- CONTROL LOGIC
- DIGITAL AUDIO ENGINE
- ARTICULATION MODULES AND CONNECTIONS
- CONTROL LOGIC
- MELODIC INSTRUMENT
- DRUM KIT
- NOTE EXCLUSIVITY
- VOICE ALLOCATION
- BANK SELECT AND PROGRAM CHANGE
- DIGITAL AUDIO ENGINE
- DIGITAL OSCILLATOR
- DIGITALLY CONTROLLED AMPLIFIER
- ARTICULATION MODULES AND CONNECTIONS
- LOW FREQUENCY OSCILLATOR
- ENVELOPE GENERATOR
- PERFORMANCE CONTROLLERS
- ARTICULATION ARCHITECTURE
- DATA OBJECTS
- OBJECT HIERARCHY
- DATA FORMATS
- INSTRUMENT
- REGION
- WAVE LINK
- ARTICULATION
- WAVE SAMPLE
- MINIMUM REQUIREMENTS
- IMPLEMENTATION NOTES
- DEVICE DRIVER DESIGN NOTES
- APPLICATION DESIGN NOTES
- INSTRUMENT DESIGN NOTES
- EXAMPLES
- DLS-1 SYSTEM MESSAGES
CHAPTER 2: FILE FORMAT
- PURPOSE
- ADVANTAGES OF THE DLS FORMAT
- DOWNLOADABLE SOUND COLLECTION RIFF FILES
- LIST CHUNK
- COLLECTION HEADER CHUNK
- DLSID CHUNK
- INSTRUMENT HEADER CHUNK
- REGION HEADER CHUNK
- LEVEL 1 ARTICULATOR CHUNK
- WAVE LINK CHUNK
- WAVE SAMPLE CHUNK
- POOL TABLE CHUNK
- VERSION CHUNK
- INFO LIST CHUNK
- CODING REQUIREMENTS AND RECOMMENDATIONS
- FILE EXAMPLES
- GENERIC DLS LEVEL 1 FILE
- DLS LEVEL 1 FILE WITH 3RD PARTY EXTENSIONS
- PROPRIETARY CHUNK IDS
- APPENDIX A - PARAMETER UNITS
- APPENDIX B - TRANSFORM AND PAN FUNCTIONS
- APPENDIX C - DLS HEADER FILE
- APPENDIX D - DLS LEVEL 1 WAVE FILE FORMAT
- DATA PACKING FOR WAVE_FORMAT_PCM FILES
- DATA FORMAT OF THE WAVE_FORMAT_PCM SAMPLES
- APPENDIX E - INSTRUMENT OBJECT HIERARCHY AND <DLS FORM>
- REFERENCES
CHANGES IN VERSION 1.1, January 1999
- General: Terms of reference more consistent.
- Chapter 1:
- Articulation Modules: LFO: Clarifies curve of LFO for volume and pitch.
- Performances Controllers: PAN: Corrected pan formula expression.
- Figure 16 (Connection Graph): Corrected CID numbers.
- Table 1 (Connection Block Table): Changed articulator Names to be consistent with text.
- Table 2 (Default, Minimum and Maximum Values): Corrected LFO Start Delay, Atten Scale and Mod to Atten default values
- Data Formats: Corrected attenuation data format explanation.
- Examples:
- Table 3 (Parameter Table):
- - Corrected headings to match text.
- - Corrected LFO start delay Lscale value.
- - Changed expressions in EG1 example.
- - Changed pitch calculations.
- - Changed attentuation calulations.
- Table 3 (Parameter Table):
- Chapter 2: Coding Requirements: Added text that inferred connections must not be written to DLS file.
- Version 1.1 Errata
- - Explanation of Attenuation vs. Gain (Entire Specification).
- - Explanation of default note exclusivity behavior.
- - New envelope digram (Figure 12) and segment descriptions.
- - New <wsmp-chk> description
CHANGES IN VERSION 1.1b, September 2004
- This is just an editorial change, correcting a misstatement regarding resetting of Expression (CC11) on reception of the Reset All Controllers message. Expression should be reset.
DLS Synth/Author:
DLS File Creator/Editor and Compatible Software Synthesizer For
Microsoft Windows 95
DLS Synth/Author is no longer available. DLS Synth/Author has been superceded by Microsoft's DirectMusic Producer. Please contact Microsoft at directx@microsoft.com for details.
Ordering Information
The Downloadable Sounds Level 1 Specification document is available in Acrobat format for free download.