Sound Designers

Peak and Loudness meters are shown beside each other; when in stereo, the L and R channels have separate Peak meters, with a summed Loudness meter which has 6dB subtracted from it (L+R-6dB). Although the true energy the ears are exposed to by stereo signals is indeed the sum of L and R energies, by subtracting 6dB from the loudness meter, it’s easier to evaluate the Peak/RMS relations of the signal. This is because summed left/right signlas can have peaks as much as 6dB higher than either channel separately.
You can select Peak or RMS measurement for the Loudness meter, which is also affected by the selected weighting curve (unweighted, dBA, dBB, dBC).