MKV to SOU Converter

Extract raw SOU audio data from MKV video files

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Pure Raw Audio

SOU delivers uncontainerized 8-bit PCM data. Extract raw MKV audio for direct use in embedded systems and legacy hardware.

Cloud Processing

No local audio tools needed. Convertio.tools handles the extraction remotely — upload the MKV and collect the SOU output.

Instant Delivery

Audio extraction from MKV is trivially fast. Your SOU file is ready within seconds, regardless of the video duration.

How to convert MKV to SOU

1

Select files from Computer, Google Drive, Dropbox, URL or by dragging it on the page.

2

Choose sou or any other format you need as a result (more than 200 formats supported)

3

Let the file convert and you can download your sou file right afterwards

About formats

MKV (Matroska Video) is an open-standard multimedia container format developed by the Matroska project, which announced the format in December 2002. Named after the Russian matryoshka nesting dolls, the format is built on the Extensible Binary Meta Language (EBML), a simplified binary variant of XML that provides a flexible and forward-compatible structure. MKV can hold virtually unlimited numbers of video, audio, and subtitle tracks within a single file, supporting codecs from H.264 and HEVC to VP9 and AV1 for video, and AAC, FLAC, Opus, and DTS for audio. A standout feature is comprehensive subtitle support, handling formats from simple SRT text to complex ASS styled subtitles and bitmap-based PGS tracks from Blu-ray discs. MKV also supports chapter markers, attachments (such as fonts needed for styled subtitles), and tagging metadata, making it one of the most feature-rich containers available. The open specification ensures that any developer can implement MKV reading and writing without licensing fees, which has driven widespread adoption across media players, streaming tools, and encoding software. The ability to encapsulate virtually any codec combination in a single, well-organized file has made MKV the preferred container for high-quality video distribution, archival, and personal media libraries.
Developer: Matroska
Initial release: December 6, 2002
SOU is a raw audio format designation that functions as an alias for unsigned 8-bit PCM data (u8) in the SoX audio processing framework. Files with the .sou extension contain headerless, uncompressed audio samples stored as unsigned 8-bit integers — each byte represents a single amplitude value from 0 to 255, with 128 as the silence midpoint. Because there is no header, playback parameters such as sample rate and channel count must be specified externally. The default assumption is typically mono at 8000 Hz, though the data can represent any rate the recording hardware supported. The u8 encoding that SOU aliases is one of the simplest possible digital audio representations, predating structured audio containers like WAV and AIFF. Raw unsigned PCM was commonly produced by early sound cards and digitizers in the late 1980s and early 1990s, when storage constraints and limited processing power made headerless formats a practical choice. One advantage is absolute simplicity: SOU files can be read by any program capable of basic file I/O, with no parsing of container structures or metadata decoding required — useful for embedded systems, hardware diagnostics, and educational contexts where audio fundamentals are being explored. The format's minimal overhead also means that conversion to any modern container is lossless and instantaneous, since the raw PCM samples can be wrapped in a WAV or AIFF header without any transcoding.
Developer: SoX Contributors
Initial release: 1991

Frequently Asked Questions

Why convert MKV to SOU?

SOU is a raw 8-bit PCM audio format used in legacy applications and embedded systems. Required when those platforms need uncontainerized audio.

What reads SOU files?

SoX and raw PCM audio importers handle SOU data. Any tool that accepts unsigned 8-bit PCM with specified parameters can process it.

Is SOU different from FSSD?

Both are 8-bit unsigned PCM raw formats. They serve similar purposes — the distinction lies in naming conventions used by different tools.

Are SOU files very large?

8-bit PCM at typical sample rates produces modest file sizes. However, without compression, longer audio will still grow proportionally.

Is the conversion secure?

Yes — your MKV upload is erased post-conversion, and the SOU output is purged within 24 hours from convertio.tools servers.