SPH to AU Audio conversion is the process of transforming a SPHERE (.sph) audio file—commonly used in speech research and telephony corpora—into an AU (.au) audio format used by Sun/NeXT systems and many Unix tools. This conversion remaps container metadata and raw PCM or encoded audio samples into the AU header and data layout so the resulting file can be played or processed by software that supports the AU format.
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Read guide →Drag your .SPH file from your computer or use the browse function.
Confirm .au as the selected destination format.
Click "Convert" and download your converted .AU file once ready.
SPH files commonly use the audio/x-speex MIME type and are associated with raw or lightly compressed speech data. AU Audio files use the audio/basic or audio/ulaw MIME types and can incorporate codecs such as u-law and PCM. While SPH focuses on speech clarity in research, AU Audio is optimized for general audio playback and editing purposes.
The AU Audio (.AU) format is commonly used for audio. Understanding its characteristics can be helpful when converting to or from other formats like SPH.
While specific technical details aren't available here, AU Audio files generally serve the purpose of storing audio effectively within their domain.
Our Online SPH to AU Converter allows you to convert your SPH files into AU Audio format effortlessly. Designed for both professionals and casual users, this tool ensures a smooth transition between these two audio file types without compromising quality or speed.
SPH files typically store raw audio data originally used in speech research and specialized applications, while AU Audio is a more flexible audio file format favored in professional audio editing and playback. Unlike SPH, AU supports various codecs and is compatible with a broader range of audio software and hardware devices.
Keep individual files under 250 MB for fastest browser-based conversion; split large corpora into chunks for reliability.
To preserve quality, choose linear PCM (16-bit or 32-bit) AU output and match the original sample rate; avoid unnecessary resampling.
For batch conversions, use a command-line tool or batch feature in conversion services to process multiple SPH files while retaining filenames and metadata.
Note format-specific limitation: SPH may include rich annotation and channel metadata that AU headers do not support; export annotations separately if required.
This converter saved me hours of manual conversion work.
John M.
Audio Engineer
Easy to use and the audio quality stayed intact.
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Podcast Producer
Perfect tool for quick SPH to AU conversions without hassle.
Mark D.
Sound Designer
Start your free SPH to AU conversion now.
Drag your file here to to upload.
Up to 250MB
If source SPH uses μ-law or A-law, convert to linear PCM only if you need editing; otherwise exporting AU with the same companding preserves file size and compatibility.