Peak volume refers to the point in an audio file which has the highest signal strength. It is a key factor in sound recording and reproduction. It isn’t representative of overall loudness because it might only last for a millisecond. If it is too high though it can indicate that the signal is being clipped and distortion is being introduced, reducing the listening experience. This headroom is also needed to ensure files are successfully encoded.
Peak volume needs to be high enough to allow for hearing enough dynamic range but it has to be measured in combination with LUFS (loudness). It can be a balancing act to meet standards in both and sometimes you’ll need to use dynamic range compression to get there.
Music, television, filmmaking, web content all have varying guidelines and best practices to be aware of. If you do nothing else, the main requirement is just make sure the peak is a little bit below 0dB. Software can bring the peaks down but if it was already at/above 0dB then the damage has already been done so try to make sure there aren’t peaks at the point of recording from the microphone.
Apple is the most influential body involved in the setting of podcast standards and they recommend that “true-peak value doesn’t exceed -1 dB FS”. We agree that the peak should be below -1 dB.
Header photo courtesy of @chairulfajar_
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It checks things like loudness, silences, restarted sentences, encoding, swearing and metadata.
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