AU Audio to SD2 conversion is the process of transforming audio files in the AU (Sun/Next .au) format into SD2 (Sound Designer II) files used historically on Macintosh and Pro Tools systems. This conversion re-encodes or repackages audio data so it’s compatible with legacy SD2-based workflows and software while preserving sample rate and channel information where possible.
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Drag your .AU file from your computer or use the browse function.
Confirm .sd2 as the selected destination format.
Click "Convert" and download your converted .SD2 file once ready.
AU files typically use the audio/basic or audio/au MIME type and are often encoded with simple PCM or u-law codecs. SD2 files use the audio/x-sd2 MIME type and are designed for professional use, supporting higher bit depths and sampling rates, often encoded with proprietary Digidesign codecs.
The SD2 (.SD2) format is commonly used for audio. Understanding its characteristics can be helpful when converting to or from other formats like AU Audio.
While specific technical details aren't available here, SD2 files generally serve the purpose of storing audio effectively within their domain.
Convert your AU Audio files to the SD2 format effortlessly with our reliable online converter. Designed for quick and secure file transformation, our tool supports high-quality audio conversion without the need for complex software.
AU Audio is a classic audio format primarily used on Sun Microsystems systems, known for its simplicity and limited compatibility. In contrast, SD2 offers higher fidelity and is favored in professional audio environments, providing better support for multi-channel and high-resolution audio.
Keep source AU files under 250MB for fastest web-based conversion; split very long sessions into tracks for easier handling.
To preserve quality, match the original sample rate and choose 24-bit SD2 output when the AU file is high-resolution.
For batch conversions, use a desktop audio tool or a converter that supports queued jobs to maintain filenames and metadata consistently.
Note format-specific limitation: SD2 is an older Apple/Pro Tools format and may not support newer metadata tags or some modern channel layouts (surround formats).
This AU to SD2 converter saved me hours of manual work.
Michael R.
Audio Engineer
Quick, easy, and the audio quality is excellent.
Emma L.
Music Producer
Perfect for converting legacy AU files to a usable format.
Jason K.
Podcaster
Start your free AU to SD2 conversion now.
Drag your file here to to upload.
Up to 250MB
If you need smaller files after conversion, compress SD2 files with a lossless archive (ZIP) rather than using lossy codecs to avoid audio degradation.