Ableton Forum

I've been trying a few different RMS meters on my master track , mvMeter2 by TB Proaudio, and various M4L devices. all of them give similar readings.
However, for any audio, they are all consistently about 3 or 4dB lower than Live's RMS meters on the master track. Why is this?

Ok the answer is ... thete are different standards for rms meters. LIve uses a standard that is based on a sine wave at 0dB giving an RMS of 0dB. The reference level of the RMS is arbitrary since the RMS is not audio, its a value based on the audio. Hence different standards of what level the RMS should be in relation to the audio. Upshot is - add 3dB to my m4l meters and all is good