Definition(en): RF64 is a Broadcast Wave compatible multichannel file format enabling file sizes to exceed 4 GB. The file format is based on the Microsoft RIFF/WAVE format and Wave Format Extensible for multichannel parameters. Additions are made to the basic specification to allow for more than 4 GB file sizes when needed (the new maximum filesize is now approximately 16 exabytes). An RF64 file containing the bext chunk becomes a Multichannel Broadcast Wave format. Further research is required to better understand this format. Users with samples are encouraged to contact the PRONOM team.