Convert MOD to ALAC — Free Online Converter

The MOD file format, originating from the Commodore Amiga's Ultimate Soundtracker in 1987, is one of computing's most influential audio formats. It introduced the tracker paradigm where music is composed by placing note events on a grid pattern, each referencing one of up to 31 embedded instrument samples. These 8-bit samples, originally constrained by the Amiga's Paula sound chip to four hardware-mixed channels, are pitched in real-time according to Amiga period values and processed through effect commands like portamento, vibrato, and arpeggio. The result is a compact, self-contained music file that was the soundtrack to thousands of Amiga demos, games, and multimedia productions throughout the late 1980s and 1990s.

ALAC (Apple Lossless Audio Codec) is Apple's proprietary lossless compression format, storing audio in an M4A container with roughly 50-60% of the original PCM file size while preserving every sample bit-perfectly. Converting MOD to ALAC synthesizes the tracker data into a continuous audio stream and then applies lossless compression, producing a file that integrates natively with the Apple ecosystem — iTunes, Apple Music, iPhone, iPad, Mac — while occupying significantly less space than an uncompressed WAV or AIFF rendering.

Apple device users who discover the world of tracker music — through retro gaming, the demoscene revival, or chiptune culture — need a way to listen to MOD files in their native music ecosystem. ALAC is the only lossless format that integrates seamlessly with iTunes, Apple Music, iPhone, HomePod, and AirPlay. Converting MOD to ALAC means every nuance of the rendered module is preserved without compromise, and the files slot into existing Apple music libraries alongside professionally mastered tracks.

Musicians who sample or remix tracker music in Apple-native DAWs like Logic Pro benefit from ALAC's lossless nature. Unlike AAC, which introduces subtle compression artifacts that compound through multiple processing stages, ALAC provides bit-perfect source audio for sampling, time-stretching, and pitch-shifting. The smaller file size compared to AIFF or WAV is a practical bonus when working with large libraries of rendered module files.

The conversion pipeline begins with FFmpeg's module decoder parsing the MOD binary structure — 31 instrument headers, the 128-entry pattern order list, and the packed pattern data where each cell encodes note period (12-bit), instrument number (4-bit + 4-bit), and effect command (12-bit) across 4 bytes per channel per row. The rendering engine processes 6 ticks per row at 125 BPM by default (50 Hz Amiga VBLANK timing), synthesizing audio by fetching samples from the embedded sample bank, applying pitch via period-to-frequency conversion, and processing effect chains. The stereo PCM output feeds into FFmpeg's ALAC encoder, which applies adaptive linear prediction, Rice coding for residuals, and decorrelation between stereo channels. The result is wrapped in an M4A (MP4) container with proper ALAC codec tags for Apple ecosystem recognition.