Audio File Formats for Podcasters
Now that your podcast has been recorded and mixed, it’s time to print the file, which format do you choose? There are many formats to choose from including: MP3, WAV, FLAC, and more. Which file format you bounce down to will depend on what you plan on doing with the file, or where you are going to host the recording. And each file format will have different levels of quality, so if possible, choose the highest bit depth and sample rate appropriate for the venue.
WAV (Waveform Audio File) – Wav files are CD quality and should be used when creating any physical reproduction of the recording, i.e. CDs, vinyl, cassettes, etc. They should also be used when passing files back and forth for mixing, or when working with a composer to add music to the production. For passing files back and forth use 41k 32bit (or higher) files, and for CD or reproduction use 41k 16bit files.
MP3 (MPEG-1 Audio Layer III or MPEG-2 Audio Layer III) – MP3 is a form of compression and will take up much less space when bounced down. For this reason it is the preferred format for most podcast hosting services. MP3s have a variety of possible export settings ranging from 320k to 8k.
FLAC (Free Lossless Audio Codec ) – FLAC is similar to MP3 but can reduce the file size up to 70%. It is an ideal file type for longer recordings, but make sure to check that where you are hosting your file accepts FLACs.
AIFF (Audio Interchange File Format) – AIFF files are generally associated with Mac computer programs and can be used when passing files back and forth during production but will not be accepted by most hosting platforms. Be sure to convert these files to WAV, MP3, or FLAC before uploading to your hosting service.
Platforms and which files they will accept:
Bandcamp – Bandcamp will allow you to host MP3s, WAVs, and FLAC. When possible, always use the highest quality file, so a WAV is preferable. Bandcamp lets you upload audio files of up to 291MB (if you’ve sold over $20 worth of files they will raise this to 600MB), so if you have a particularly large file you’ll want to convert it to a FLAC.
Podomatic and other hosting services – Podomatic will automatically squash your MP3 files into 192k, always make sure to upload at this bitrate, anything higher will just eat up your storage space and be further compressed. This will be the case for most hosting sites, but make sure to always upload the highest quality file that they will accept without automatically changing the bitrate.
Radio4All – Will allow you to host MP3 files of up to 320k but will also accept lower bitrate files, and there are no restrictions on storage.
Youtube – Youtube, Vimeo, and other video platforms will not allow you to upload audio files, so you will have to marry the audio file with an image or video and export the combination as an MP4, MOV, AVI, WMV, or other accepted video files. These files will take up much more space on your computer, so you will want to store them on a backup hard drive if you plan to keep them for later use.
Metadata and Naming files correctly:
When exporting your finished file from your DAW you will be given the option of entering the metadata, this is an important step and should not be skipped. If you are producing a podcast, or any type of series, you will want to make sure that your metadata is consistent because this info will show up in iTunes, or wherever your listener is storing and listening to the files. It is worth having a master spreadsheet to keep track of how you are entering this info because even the slightest variation will cause the file to show up as a different artist or album. The following items are information you will want to include: name of the show, episode title, track # (if relevant), release date, website URL, and anything else you’ll want the listener to know. Also be sure to put the bitrate in the name of the file if you are exporting multiple files of different qualities, as this will help you differentiate which file is which without having to look at the properties.
Jean-Paul L. Garnier
Jean-Paul L. Garnier lives and writes in Joshua Tree, CA where he is the owner of Space Cowboy Books, a science fiction bookstore, independent publisher, and producer of Simultaneous Times podcast. In 2020 his first novella Garbage In, Gospel Out was released by Space Cowboy Books and in 2018 Traveling Shoes Press released Echo of Creation, a collection of his science fiction short stories. He has also released several collections of poetry: In Iudicio (Cholla Needles Press 2017), Future Anthropology (currently being translated into Portuguese), and Odes to Scientists (audiobook - Space Cowboy Books 2019). He is a two time Elgin Nominee and also appeared in the 2020 Dwarf Stars anthology. His new collection of SF poetry, Betelgeuse Dimming has just been released and is available as a free download audiobook / ebook at spacecowboybooks.bandcamp.com. He is also a regular contributor for Canada’s Warp Speed Odyssey blog. His short stories, poetry, and essays have appeared in many anthologies and webzines.