True Peak limiters along with True Peak Metering are essential for anyone working to BS1770 based delivery specs and that includes people in broadcast audio and post production but more and more involved in music production as more and more music delivery systems use loudness and true peak in their delivery specs. So which true peak limiter plug-in do you use? If you use more than one, vote for the one which you use most and tell us in the comments why.

Most limiters base their limiting on the sample data in the digital audio signal. This type of limiter can only respond to the sample values and doesn't know what happens between the samples or what is called the ‘true peak’ of the audio. We need to consider what might be going on between the samples and how that will impact the digital to analogue conversion further downstream.

All digital audio must be converted back to analogue at some point so we can hear it with our analogue ears. As part of this D-A conversion, a reconstruction filter is applied to round off the stepped digital audio signal. This can be an issue especially close to digital headroom and also when audio is processed through 'lossy' codec like mp3, AAC or mp4.  The closer we work to digital headroom the more important it is we know what is happening between the samples and what will happen when digital audio is converted back into analogue. With the loudness related workflows in broadcast content delivery and with music streaming services more and more likely to specify loudness and true peak in their delivery specs. We need tools that know where the true peaks are.