VOC to AU Converter

How to Convert VOC to AU Online

1. Upload Your VOC File: Drag and drop or click "+ Add Files" to select Creative Voice files from your computer. Batch upload is supported — convert an entire folder of Sound Blaster recordings in one pass.
2. Pick Audio Codec and Sample Rate: Default codec is mu-law (the AU standard for telephony and early-web audio). Choose PCM 16-bit big-endian for lossless archival, A-law for European telephony pipelines, or keep mu-law for the canonical Sun/NeXT 8-bit voice profile. Set Audio Sample Rate to Original to preserve the source clock, or pick 8000 Hz / 11025 Hz / 22050 Hz / 44100 Hz / 48000 Hz.
3. Set Audio Channels and Trim (Optional): Switch Audio Channel between Original, Mono (smaller files, fine for speech), or Stereo. Use the Trim control to clip the start offset or limit duration when you only need a fragment of a long VOC capture.
4. Convert and Download: Click "Convert" and save your AU file. Conversion runs server-side over HTTPS, files are auto-deleted after processing — no sign-up, no watermark, no file-count limit.

Why Convert VOC to AU?

The Creative Voice (VOC) format was Creative Labs' container for Sound Blaster audio in the late 1980s and 1990s — block-structured, 8-bit PCM by default, with later support for 16-bit and a-law/u-law variants. AU (.au / .snd) is Sun Microsystems' simpler big-endian format that became the default audio container on NeXTSTEP, Solaris, and the early web. Both are obsolete-but-alive formats; converting VOC to AU is most often about portability and toolchain compatibility, not quality.

• Unix and Solaris pipelines — AU is the native audio format for Sun's audiotool, sox, and Solaris /dev/audio. Legacy scientific and signal-processing rigs still ingest .au; VOC files won't load without a wrapper.
• Java audio (javax.sound.sampled) — Java's standard audio API reads AU out of the box across every JDK since 1.3 (1999). VOC requires a third-party SPI like Tritonus, so converting upstream is simpler than shipping extra JARs.
• DOS game audio preservation — Many DOS titles (Duke Nukem 3D, Spear of Destiny, In Search of Dr. Riptide) shipped sound effects as .voc. Re-encoding to AU lands them in a format that modern Linux/BSD audio tools handle natively.
• Academic speech corpora — Older linguistics and phonetics datasets distributed on .au at 8 kHz mu-law (the "Sun audio" voice profile). Converting VOC recordings into the same encoding keeps datasets internally consistent.
• Cross-platform sharing — AU plays on macOS QuickTime, VLC, Audacity, and most Unix media players without extra codecs. VOC is essentially Windows/DOS-only on modern systems.
• Smaller telephony-grade files — Mu-law AU at 8 kHz mono is roughly 8 KB per second of audio — about 1/6 the size of CD-quality PCM — and stays intelligible for voice. Useful when you're archiving spoken-word VOCs and don't need fidelity beyond a phone call.

VOC vs AU — Format Comparison

Codec & Quality Quick Guide

For most VOC sources (which are typically 8-bit recordings from Sound Blaster hardware), mu-law gives you the smallest file with no perceptible quality loss versus the original. Pick PCM 16-bit only if you plan to do further editing or measurement — re-encoding 8-bit voice to 16-bit doesn't add fidelity, it just adds zeros.

Frequently Asked Questions

What programs open .au files in 2026?

VLC, Audacity, ffmpeg, sox, QuickTime Player, Windows Media Player (with codec pack), and any Java application using javax.sound.sampled. On Linux the audio/basic MIME type maps directly to .au, and most desktop file managers preview it without extra software.

Should I pick mu-law, A-law, or PCM as my AU codec?

Mu-law is the canonical AU default and what NeXTSTEP/Solaris pipelines expect for voice. A-law is the European-telephony equivalent (same bit rate, slightly different companding curve). Pick PCM 16-bit big-endian if you need a lossless archival copy and don't care about file size. For converting 8-bit VOC source material specifically, mu-law is the natural target — it's also 8-bit and was designed for the same voice-quality range.

Will the converted AU play in Java applications?

Yes — that's one of AU's main remaining use cases. Java's javax.sound.sampled.AudioSystem has built-in support for AU (mu-law, A-law, 8-bit PCM, 16-bit PCM) on every JDK since 1.3. If your Java app currently relies on a third-party VOC reader, converting upstream to AU removes the dependency.

Why is my AU file roughly the same size as the VOC?

Because AU at mu-law 8-bit and VOC at unsigned 8-bit PCM both pack one byte per sample. The main differences are header layout (24 bytes for AU vs 26 bytes plus per-block metadata for VOC) and endianness. If you want a smaller file, drop the sample rate (8 kHz instead of 22.05 kHz) or convert to a compressed format like VOC to MP3 or VOC to FLAC instead.

Is AU the same as SND?

Practically yes. On NeXTSTEP the format was distributed as .snd; on Sun it became .au. The file magic is the same four bytes (.snd). Some legacy macOS tools still write .snd extensions on what are structurally identical AU files. Both extensions are interchangeable in modern players.

Will my Sound Blaster ADPCM-compressed VOC convert correctly?

Yes. Creative ADPCM (the 4-bit and 2.6-bit variants introduced in VOC v1.20) is decoded back to linear PCM before encoding to your chosen AU codec, so there's no silent passthrough of compressed bytes. Expect the AU output to be larger than the VOC source because ADPCM is compressed and the AU mu-law/PCM target is not.

Does AU support stereo, or is it mono-only?

AU supports any channel count the encoding does — common files are mono (the historical default for voice/telephony) but stereo, 4-channel, and even surround layouts are valid. The Audio Channel option in Advanced Options lets you force mono (smaller file, fine for VOC speech samples) or stereo (duplicates the mono signal across both channels for compatibility with stereo-only players).

Can I trim a long VOC during conversion?

Yes — open Advanced Options, expand Trim, and set a start offset and duration. Useful when a VOC contains multiple sound effects concatenated into a single file (a common pattern in DOS game audio dumps) and you only want one. For more flexible audio editing, the standalone Audio Converter lets you mix codecs and operations across batches.

What's the maximum file size I can upload?

VOC files are almost always small — a few hundred KB to a few MB, because the format dates from an era when 1 MB of RAM was a lot. xconvert handles standard uploads with no per-file watermark or count limit; batch-converting a large game audio dump is fine — files are processed on our servers over an encrypted connection.