What LUFS and true peak measure
LUFS, also written LKFS, measures how loud audio sounds to a listener. For an episode the usual figure is integrated loudness: one number for the whole file.
True peak, in dBTP, is the highest level the signal reaches once it is converted to a lossy file such as MP3, including peaks between samples that a simple meter misses. The first number sets how loud the episode feels. The second keeps it from distorting.
What the platforms say
Apple’s podcast requirements recommend an overall loudness of around −16 LKFS, with a tolerance of ±1 dB, and true peaks that do not exceed −1 dB, measured to the ITU-R BS.1770 standard.
Spotify says it normalises loudness to about −14 LUFS during playback, and sources disagree on whether podcasts have a separate target. Where a player normalises to −14 LUFS, an episode mastered at −16 may play about 2 dB louder than mastered. Keeping the peak below −1 dBTP leaves room for that change.
Platform recommendations change, so check each page before you publish.
The spec we deliver to
Every episode we deliver meets the same numbers.
- Integrated loudness: −16 LUFS, within ±1 dB.
- True peak: never above −1 dBTP.
- One finished file per episode, in the format agreed in your quote.
- Every file measured against the spec before it leaves us.
Why −16 and not louder
A louder master is not a better one. Pushing speech to −14 or higher means compressing it harder, which flattens the voices and brings up breaths and room noise. −16 leaves room for the natural changes of level in speech and matches the number Apple recommends.
File format and bitrate
For a voice-only show a mono file keeps the size down; stereo helps when music has a stereo image. Apple’s requirements list recommended bitrates by sample rate and channel count, and platforms differ, so confirm the figures on the platform page. We deliver the format agreed in your quote.
How we check
Before an episode is delivered, the finished file is measured for integrated loudness and true peak, and the readings are compared with the spec above. An episode that falls outside it is not delivered until it is corrected.