AU Audio to VOX conversion is the process of transforming audio files in the AU (Sun/NeXT audio) format—commonly raw or µ-law/linear PCM encapsulated in .au headers—into VOX files that use Dialogic ADPCM compression (.vox) often used for telephony and voice-recording systems. This conversion re-encodes the audio stream to the VOX codec and can include sample-rate and bit-depth adjustments to match telephony or archival playback requirements.
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Drag your .AU file from your computer or use the browse function.
Confirm .vox as the selected destination format.
Click "Convert" and download your converted .VOX file once ready.
AU files usually have the MIME type audio/basic and store raw or mu-law encoded audio primarily for Unix systems. VOX files use the audio/x-adpcm MIME type and support Dialogic ADPCM codec, optimized for voice data compression. VOX is commonly used in telephony and voicemail systems due to its efficient encoding.
The VOX (.VOX) 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, VOX files generally serve the purpose of storing audio effectively within their domain.
Convert your AU Audio files to VOX format online quickly and efficiently with our specialized AU to VOX converter. Whether you need better compatibility or smaller file sizes, our service offers a seamless solution tailored for audio file conversion.
AU Audio files are typically uncompressed and used mainly on Sun Microsystems systems, offering high fidelity but large file sizes. VOX files use ADPCM compression, making them smaller and ideal for voice recordings and telephony applications. Choosing VOX over AU is beneficial for efficient storage and broader device compatibility.
Keep individual AU source files under 250 MB for smooth browser-based conversion; downsample or split larger recordings before converting.
Preserve quality by normalizing levels and converting 16-bit linear AU to 8/16-bit intermediate with dithering before ADPCM encoding to reduce quantization noise.
For telephony use, set sample rate to 8000 Hz and convert to mono; higher sample rates will be downsampled and increase file size without VOX playback benefit.
Use batch conversion for large collections but check a few samples first to confirm gain, clipping, and expected voice clarity.
This converter saved me hours of work and maintained the audio quality perfectly.
Emily R.
Audio Engineer
Quick and easy to use, the best AU to VOX tool I've found online.
Jason M.
IT Specialist
I love how fast the conversion is and how accessible the VOX format is now.
Linda K.
Podcaster
Start your free AU to VOX conversion now.
Drag your file here to to upload.
Up to 250MB
Limitation: VOX uses 4-bit Dialogic ADPCM (mono) so stereo, high-fidelity music, and multi-channel metadata will be lost during conversion.