Reference Formats
WAV
WAV is a RIFF-based container for uncompressed PCM audio, introduced by Microsoft and IBM in 1991 and still the default lossless master format for recorded sound on Windows and in professional audio.
Extension
.wav
Full name
Waveform Audio File Format
Introduced
1991
Vendor
Microsoft and IBM
What is inside the container
WAV wraps audio data in RIFF chunks and almost always holds uncompressed linear PCM, so a 3-minute stereo file at CD quality runs around 30MB. The base spec only offers a thin LIST/INFO chunk for basic tags, but the broadcast-industry extension, Broadcast Wave Format (BWF, EBU Tech 3285, 1997), adds a "bext" chunk carrying description, originator, timecode and a unique material ID that travels with the file. Because that provenance data is embedded rather than sidecar, BWF is what sound archives and production houses standardize on for field recordings and mix masters.
How to open it
For archives
WAV — specifically BWF — is the right lossless preservation format for recorded audio in a DAM: uncompressed, universally decodable, and able to carry embedded provenance metadata in its bext chunk rather than a separate sidecar file that can get separated from the asset. Keep WAV/BWF as the archival master and generate MP3 or AAC proxies for browser preview and low-bandwidth delivery, since a 4-minute WAV master can be 40MB or more. Plain WAV is capped at 4GB by its 32-bit RIFF size field; very long recordings should use the RF64 extension or be transcoded to FLAC for cheaper long-term storage without losing fidelity.
Microsoft and IBM introduced WAV in 1991 as part of their joint Multimedia Programming Interface and Data Specifications, built on RIFF (Resource Interchange File Format), a general tagged-chunk container the two companies had designed together to give Windows 3.1 a native structure for multimedia files. WAV was one of several RIFF-based formats to come out of that effort, and it became the default way Windows applications stored digital audio for the next three decades.
Structurally a WAV file is a sequence of labeled chunks — a “fmt” chunk describing sample rate, bit depth and channel count, followed by a “data” chunk holding the raw PCM samples. That simplicity is exactly what makes WAV useful as an interchange format: any tool that understands RIFF chunk parsing can read the audio without needing a codec, which is not true of compressed formats. The tradeoff is size — uncompressed PCM audio takes roughly ten times the storage of an equivalent MP3.
| Variant | Max file size | Metadata support |
|---|---|---|
| Standard WAV (RIFF) | 4GB (32-bit size field) | Basic LIST/INFO chunk only |
| Broadcast Wave Format (BWF) | 4GB (same RIFF limit) | Full bext chunk: description, originator, timecode, unique material ID |
| RF64 | Effectively unlimited (64-bit) | Same as BWF, used for very long recordings |
For a DAM, WAV’s role is almost always as the ingested master rather than the delivered file. A production audio library holding voiceover recordings, sound effects, or music masters needs the original bit-exact file preserved indefinitely, which argues for keeping WAV (ideally BWF) untouched in cold storage while the system automatically generates a compressed MP3 or AAC proxy for in-browser preview and for users who just need to review, not re-edit, the take.
Frequently asked
Should a DAM store audio as WAV masters or is MP3 enough?
Keep WAV (ideally BWF) as the preservation master and generate MP3 or AAC proxies for preview and delivery. MP3 is lossy — re-encoding or repeatedly editing a compressed file degrades it further, while a WAV master can always be re-transcoded to whatever a project needs without further quality loss.
Can WAV files carry metadata the way MP3 uses ID3 tags?
Plain WAV only has a rudimentary LIST/INFO chunk for basic fields like title and artist. The Broadcast Wave Format (BWF) extension adds a proper "bext" chunk for description, originator, timecode and a unique material ID, which is why BWF rather than plain WAV is the archival standard for field recordings.
What's the difference between WAV and BWF for asset management?
BWF is WAV plus a standardized metadata chunk (bext) defined by the EBU in 1997, designed so broadcast provenance data — who recorded it, when, and under what timecode — travels embedded in the file rather than in a separate sidecar that can get lost during transfer.
Is there a maximum file size for WAV in a DAM library?
Standard WAV is capped at 4GB because its RIFF chunk size field is 32-bit. Long-form recordings (multi-hour production sound, ambisonic captures) that exceed that need the RF64 extension, or should be transcoded to FLAC, which has no such limit and adds lossless compression.
Can a browser preview a WAV file directly from a DAM without downloading it?
Yes — HTML5's element supports WAV natively in every major browser, but because WAV is uncompressed, previewing a large master over a slow connection is impractical. Most DAMs solve this by serving a compressed MP3/AAC proxy for the preview player and reserving the WAV download for users who need the actual master.
Is WAV audio always uncompressed?
In practice yes — WAV is technically a general container that can hold compressed codecs via its format tag field, but essentially every WAV file encountered in production and archival workflows is linear PCM. If you see a WAV-labeled file with an unusual small size, verify the codec before trusting it as a lossless master.
What's the best way to batch-convert WAV masters to delivery formats?
FFmpeg is the standard tool for scripted, unattended batch conversion of WAV to MP3 or AAC at a DAM's chosen bitrate, and most DAM platforms wrap it (or a similar transcoding engine) into their automatic ingest pipeline so a proxy is generated the moment a WAV master is uploaded.
Does WAV support multichannel or surround audio for production masters?
Yes, the WAV/RIFF fmt chunk can describe any channel count and layout, including 5.1 or ambisonic captures, which is one reason it remains the standard interchange format between DAWs, post-production tools, and archival storage in a media DAM.
Sources
- WAV was introduced by Microsoft and IBM in 1991 as part of their joint Multimedia Programming Interface and Data Specifications, built on the RIFF container format. checked 2026-08-07 — Library of Congress — WAVE Audio File Format
- The Broadcast Wave Format (BWF) extension, which adds the bext metadata chunk, was standardized by the EBU and is the recommended format for archival audio digitization. checked 2026-08-07 — Library of Congress — Broadcast WAVE Audio File Format