Export Obstacle

Please lift or demolish the 4GB wav file export ceiling. I use Windows 10 Professional 64-bit and Audacity 3.0.0.

The WAV standards were developed by Microsoft. There’s a 32-bit ''data size" field in the WAV file header. If you try to “count” higher than you can go with 32-bits the number “rolls over”. i.e. If the file is slightly higher than the limit the “33rd bit” is lost (or never exists) and the other bits start-over at zero and the software will think it’s only a short audio file.

As far as I know WAV is the only audio format with an “artificial” size limit. It depends on the compatibility of whatever other software you’re using but if you want lossless FLAC (or ALAC) s probably the best option. Wave64 and RF64 are uncompressed and lossless.

I forgot about AIFF and RIFF (very similar to WAV… In fact WAV is an RIFF file).

And Apple impose the same limit with their AIFF format - it’s just a “fact-of-life”


It is not an Audacity imposed limit. It is a limitation of the WAV (and AIFF) format.

From Wikipedia: https://en.wikipedia.org/wiki/WAV#Limitations

The WAV format is limited to files that are less than 4 GiB, because of its use of a 32-bit unsigned integer to record the file size header.

The solution is to use a different format (such as FLAC, MP3, OGG, RF64, …)

If this is an insurmountable issue, why are other applications seemingly able to do the impossible? Steinberg Cubase, Cyberlink AudioDirector, and n-Track audio editor are quite able to save large wav files.

There is Broadcast Wave (BWF).

In particular, the EBU has ratified the Multi-channel Broadcast Wave Format, MBWF, which specifies the means for enhancing the RF64 wave format with BWF metadata. This development allows the use of larger files (file sizes greater than 4 Gbyte) and accommodates wave files with more than two channels [4].

That’s from Specification of the Broadcast Wave Format (BWF) - EBU tech

This is from the CuBase Instructions.

Wave 64
Wave 64 has the extension .w64, and is quality-wise sounding just like normal .wav.
So what’s the difference?
They can be even larger in file size than regular Wave. This is because Wave 64 uses 64-bit values, while regular Wave uses 32-bit.
Main use: This is ideal if you have a longer recording or project file sizes that exceed 2 GB. The more data, the more beneficial it is to use Wave 64.
Developer: Sonic Foundry

They’re both subsets of WAV. Audacity uses regular WAV because it’s practically guaranteed that everybody and everything supports it. The instant you start branching off into special variations, you run the risk of your client giving you a funny look instead of a payment for work because they can’t open it.

If you have your computer set to hide filename extensions, you would never know it’s producing either of those special formats.