NBCUniversal Podcast — Mid-roll (Client-Recorded) ads are audio files, up to 60 seconds long, delivered as WAV, AIF, FLAC, ALAC, AAC, or MP3. They run in the Podcast Mid-roll placement on NBCUniversal. Master audio at MP3 128 Kbps CBR (delivered as transcoded) and 256 kbps for consistent loudness.
| Orientation | any |
|---|---|
| File types | WAV, AIF, FLAC, ALAC, AAC, MP3 |
| Max duration | 60 sec |
|---|---|
| Audio codec | MP3 128 Kbps CBR (delivered as transcoded) |
| Audio channels | stereo (2) |
| Audio bitrate | 256 kbps |
| Sample rate | 44100 Hz |
| Bit depth | 16-bit |
Mid-roll: :60 master length. :15 and :30 cuts are available as separate spec entries. Preferred uncompressed WAV (2-channel, 16-bit little-endian, 44.1 kHz) or AIF; FLAC, ALAC, 256 Kbps AAC or MP3 also accepted. All files transcoded to MP3 128 Kbps CBR / 2-channel stereo. Assets due 5 business days before launch. No file size limit.
Official source: https://nbcu-creative-guidelines.scroll.site/nbcuniversal-creative-guidelines/nbcu-podcast-ad-guidelines-specifications