Working with CDDA Audio

CDDA (Compact Disc Digital Audio) tracks provide full CD-quality audio for PlayStation games, commonly used for background music and audio that plays independently of game data.

What is CDDA?

CDDA audio tracks:

Store uncompressed 44.1 kHz, 16-bit stereo audio
Play through the CD audio interface, not game memory
Live in separate tracks beyond the data track
Can be played on standard CD players
Support up to 99 audio tracks per disc

CDDA vs XA Audio

Feature	CDDA Audio	XA Audio
Quality	CD-quality (uncompressed)	Compressed ADPCM
Location	Separate CD tracks	Files in data track
Access	By track number	By file name
Memory	None (streams from CD)	None (streams from CD)
Storage	~10 MB per minute	~2.5 MB per minute

Use CDDA for music tracks that need maximum quality. Use XA for in-game audio that needs to be accessed by filename or when disc space is limited.

Adding CDDA Tracks

Prepare Audio Files

CDDA tracks can be created from multiple formats:

WAV: Uncompressed audio (recommended)
FLAC: Lossless compression
PCM: Raw audio data
MP3: Lossy compression (not recommended for archival)

For best results, ensure audio is in Redbook format:

Sample Rate: 44100 Hz
Bit Depth: 16-bit
Channels: Stereo

While mkpsxiso accepts MP3 files, use lossless formats (WAV or FLAC) for CD audio to maintain quality. MP3 re-encoding introduces additional quality loss.

Add Audio Tracks to XML

Define audio tracks after your data track:

<?xml version="1.0" encoding="UTF-8"?>

<iso_project image_name="myimage.bin" cue_sheet="myimage.cue">
  
  <!-- Data track -->
  <track type="data">
    <!-- ... directory_tree contents ... -->
  </track>
  
  <!-- CDDA audio tracks -->
  <track type="audio" source="audio/track02.wav"/>
  <track type="audio" source="audio/track03.wav"/>
  <track type="audio" source="audio/track04.wav"/>
  
</iso_project>

The data track is always track 01. Audio tracks start at track 02.

Configure Cue Sheet

When using CDDA tracks, you must specify a cue sheet:

<iso_project image_name="myimage.bin" cue_sheet="myimage.cue">

The cue sheet is automatically generated and describes:

Track count and types
Track start positions
Audio format specifications

Build and Verify

Build your ISO with audio tracks:

mkpsxiso myproject.xml

mkpsxiso will:

Generate the .bin file with all tracks
Create a .cue file describing track layout
Report track positions and sizes
Validate audio format

Track IDs and DA Files

Understanding DA Files

DA (Direct Audio) files are not actual audio files. They’re directory entries that link to CDDA tracks:

<directory_tree>
  <!-- Regular files -->
  <file name="game.exe" source="game.exe"/>
  
  <!-- DA files link to audio tracks -->
  <file name="track02.da" trackid="02" type="da"/>
  <file name="track03.da" trackid="03" type="da"/>
  <file name="track04.da" trackid="04" type="da"/>
</directory_tree>

<!-- Actual audio track definitions -->
<track type="audio" trackid="02" source="audio/bgm1.wav"/>
<track type="audio" trackid="03" source="audio/bgm2.wav"/>
<track type="audio" trackid="04" source="audio/bgm3.wav"/>

The trackid attribute connects DA files to their corresponding audio tracks.

Why Use DA Files?

DA files allow games to:

Browse audio tracks as if they were files
Use standard file I/O to access track information
Display track names in in-game menus
Treat audio tracks consistently with other game data

DA files appear in the directory structure with the CD-Audio attribute set, making them show as WAV files in some file browsers (though they’re just links to tracks).

DA File Placement

DA files MUST be placed last in your directory tree. Placing them earlier may corrupt your ISO image.

<directory_tree>
  <!-- All regular files first -->
  <file name="system.cnf" source="system.cnf"/>
  <file name="game.exe" source="game.exe"/>
  <dir name="data">
    <!-- ... game data ... -->
  </dir>
  
  <!-- DA files at the end -->
  <file name="track02.da" trackid="02" type="da"/>
  <file name="track03.da" trackid="03" type="da"/>
  <file name="track04.da" trackid="04" type="da"/>
</directory_tree>

Pregaps

What are Pregaps?

Pregaps are silent sections before each audio track:

Standard CD format requires 2 seconds of pregap
Track 01 (data) has a 150-sector (2 second) pregap
Audio tracks 03+ default to 2-second pregaps
Track 02 defaults to 0 seconds (no pregap)

Default Pregap Behavior

<!-- Track 02: No pregap -->
<track type="audio" source="audio/track02.wav"/>

<!-- Track 03+: 2 second pregap -->
<track type="audio" source="audio/track03.wav"/>
<track type="audio" source="audio/track04.wav"/>

Custom Pregaps

Specify custom pregap durations:

<track type="audio" source="audio/track03.wav">
  <pregap duration="00:04:00"/>
</track>

Duration format: MM:SS:FF (minutes:seconds:frames, where frames are 0-74) Examples:

00:02:00 = 2 seconds (default)
00:04:00 = 4 seconds
00:00:30 = 30 frames (~0.4 seconds)
00:10:00 = 10 seconds

Pregap duration is filled with silence. The audio source file does not include the pregap data.

Supported Audio Formats

WAV Files

<track type="audio" source="audio/music.wav"/>

Best for:

Uncompressed source audio
Direct conversion to CDDA
Fastest processing time

FLAC Files

<track type="audio" source="audio/music.flac"/>

Best for:

Lossless compression (~50% size reduction)
Archival storage
Maintaining perfect quality

FLAC is ideal for source audio files. It reduces storage requirements while maintaining bit-perfect quality.

PCM Files

<track type="audio" source="audio/music.pcm"/>

Best for:

Raw audio data
Direct from audio hardware
No container format overhead

MP3 Files

<track type="audio" source="audio/music.mp3"/>

Best for:

Quick testing
When source is already MP3

Avoid for:

Final releases (lossy compression)
High-quality music

Common CDDA Patterns

Music-Only Game

<iso_project image_name="musicgame.bin" cue_sheet="musicgame.cue">
  
  <track type="data">
    <!-- Minimal game data -->
    <directory_tree>
      <file name="system.cnf" source="system.cnf"/>
      <file name="game.exe" source="game.exe"/>
      
      <!-- DA files for all tracks -->
      <file name="track02.da" trackid="02" type="da"/>
      <file name="track03.da" trackid="03" type="da"/>
      <file name="track04.da" trackid="04" type="da"/>
      <!-- ... more tracks ... -->
    </directory_tree>
  </track>
  
  <!-- 20+ audio tracks -->
  <track type="audio" trackid="02" source="music/song01.flac"/>
  <track type="audio" trackid="03" source="music/song02.flac"/>
  <track type="audio" trackid="04" source="music/song03.flac"/>
  <!-- ... more tracks ... -->
  
</iso_project>

Background Music Tracks

<!-- Data track with game content -->
<track type="data">
  <!-- ... game files ... -->
  
  <!-- DA files at end -->
  <file name="menu.da" trackid="02" type="da"/>
  <file name="gameplay.da" trackid="03" type="da"/>
  <file name="boss.da" trackid="04" type="da"/>
</track>

<!-- Music tracks -->
<track type="audio" trackid="02" source="audio/menu_theme.wav"/>
<track type="audio" trackid="03" source="audio/game_music.wav"/>
<track type="audio" trackid="04" source="audio/boss_theme.wav"/>

Unreferenced Audio Tracks

You can add audio tracks without DA files:

<track type="data">
  <!-- No DA files -->
  <directory_tree>
    <file name="system.cnf" source="system.cnf"/>
    <file name="game.exe" source="game.exe"/>
  </directory_tree>
</track>

<!-- Audio tracks accessed by track number only -->
<track type="audio" source="audio/track02.wav"/>
<track type="audio" source="audio/track03.wav"/>

Game code accesses these tracks directly by number using CD audio commands.

Extracting CDDA Tracks

Use dumpsxiso to extract audio tracks:

Extract as WAV

dumpsxiso -x game.bin -da wav

Extract as FLAC

dumpsxiso -x game.bin -da flac

Extract as PCM

dumpsxiso -x game.bin -da pcm

Extracted tracks are saved as:

game_dump/
├── track02.wav
├── track03.wav
└── track04.wav

LBA Calculations

Track Positioning

Audio tracks are positioned after the data track:

Track 01 (Data): LBA 0 - 100,000
Track 02 (Audio): LBA 100,000 - 150,000
Track 03 (Audio): LBA 150,000 - 200,000

Generating LBA Logs

mkpsxiso myproject.xml -lba logfile.txt

The log includes:

Data track files and their LBAs
Audio track start positions
Pregap information
Total disc size

Unreferenced audio tracks (without DA files) are now listed in LBA logs as of version 2.20.

Playback in Games

CD Audio Commands

Games play CDDA tracks using LibCD functions:

// PlayStation SDK example
CdlLOC loc;
CdIntToPos(track_lba, &loc);
CdControlF(CdlPlay, (u_char*)&loc);

Track Numbers

Access tracks by number:

Track 1: Data track (don’t play as audio)
Track 2+: Audio tracks

Or via DA files using standard file operations.

Troubleshooting

Incorrect Track Length

If track lengths are wrong:

Verify source audio is correct format (44.1 kHz, 16-bit, stereo)
Check for file corruption
Re-export from original source

Audio Not Playing

If audio doesn’t play:

Verify cue sheet was generated
Check track numbers in game code
Test in different emulators
Verify on actual hardware

DA Files Not Visible

If DA files don’t appear:

Ensure type="da" is specified
Verify trackid matches actual track
Check DA files are placed last in directory tree

Cue Sheet Missing

If no cue sheet is generated:

Add cue_sheet attribute to <iso_project>
Ensure at least one audio track exists
Check for build errors in console output

Best Practices

CDDA Best Practices:

Use FLAC for source audio (lossless, smaller than WAV)
Always specify Redbook format (44.1 kHz, 16-bit, stereo)
Place DA files last in directory tree
Test on real hardware for accurate playback
Keep track count reasonable (under 20 for most games)
Use descriptive trackid values for clarity

Audio Quality

Never use lossy formats for final builds
Maintain 44.1 kHz sample rate
Keep bit depth at 16-bit
Use stereo (not mono or surround)

Organization

<!-- Clear organization -->
<track type="audio" trackid="02" source="music/01_title_screen.flac"/>
<track type="audio" trackid="03" source="music/02_gameplay_1.flac"/>
<track type="audio" trackid="04" source="music/03_gameplay_2.flac"/>
<track type="audio" trackid="05" source="music/04_boss_theme.flac"/>

Use descriptive filenames that indicate track purpose.

Next Steps

Combine with XA Audio for in-game sounds
Add STR Video with synced audio
Learn about LBA Optimization for audio tracks
Understand License Data for bootable discs

Getting Started

Commands

XML Configuration

Guides

Reference

​What is CDDA?

​CDDA vs XA Audio

​Adding CDDA Tracks

​Track IDs and DA Files

​Understanding DA Files

​Why Use DA Files?

​DA File Placement

​Pregaps

​What are Pregaps?

​Default Pregap Behavior

​Custom Pregaps

​Supported Audio Formats

​WAV Files

​FLAC Files

​PCM Files

​MP3 Files

​Common CDDA Patterns

​Music-Only Game

​Background Music Tracks

​Unreferenced Audio Tracks

​Extracting CDDA Tracks

​Extract as WAV

​Extract as FLAC

​Extract as PCM

​LBA Calculations

​Track Positioning

​Generating LBA Logs

​Playback in Games

​CD Audio Commands

​Track Numbers

​Troubleshooting

​Incorrect Track Length

​Audio Not Playing

​DA Files Not Visible

​Cue Sheet Missing

​Best Practices

​Audio Quality

​Organization

​Next Steps

Build docs developers (and LLMs) love

What is CDDA?

CDDA vs XA Audio

Adding CDDA Tracks

Track IDs and DA Files

Understanding DA Files

Why Use DA Files?

DA File Placement

Pregaps

What are Pregaps?

Default Pregap Behavior

Custom Pregaps

Supported Audio Formats

WAV Files

FLAC Files

PCM Files

MP3 Files

Common CDDA Patterns

Music-Only Game

Background Music Tracks

Unreferenced Audio Tracks

Extracting CDDA Tracks

Extract as WAV

Extract as FLAC

Extract as PCM

LBA Calculations

Track Positioning

Generating LBA Logs

Playback in Games

CD Audio Commands

Track Numbers

Troubleshooting

Incorrect Track Length

Audio Not Playing

DA Files Not Visible

Cue Sheet Missing

Best Practices

Audio Quality

Organization

Next Steps