FabFilter User Forum
Pro C2 Loudness Meter doesn't match L2 or Cubase?
Can anyone confirm/explain why the momentary loudness display on C2 is 3dB lower than the reading on L2 and the meter in the Cubase control room?
Thanks.
Dan Johnson — Apr 29, 2024
Hi Dan,
Pro-C 2 does not have a loudness meter like Pro-L 2 has. Pro-C 2 just shows RMS and peak levels.
Hi Ralph,
Thanks for the reply; according to the C2 manual -
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Peak level and loudness level metering
At the right of the interface, there are three accurate peak level meters that display the current input, gain reduction and output levels. The read-outs above the level meters show the highest measured peak value, until you click on them.
Aditionally, the input and output meters also show the loudness level (per channel) on top of the peak level. The loudness level complies with the Momentary mode of the EBU R128 / ITU-R 1770 standards.
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Is this just an error in the manual?
That's my bad, I was under the impression it was just RMS.
I just compared the two, and even though the meters are not aligned to the same scale, their levels do seem to match. Could you send me a video that shows the difference between the two?
It looks like the Pro-C 2 meters are measuring per-channel, so I think this is just the difference between mono versus stereo measurement.
I just tried on a mono audio track and the loudness numbers match. If you convert that to stereo (duplicating the mono audio on both L and R channels of a stereo track), Pro-C 2's loudness bars show as ~3 dB (LU) lower than the (stereo) momentary loudness measurements in Pro-L 2 or Cubase's loudness meter.
Agree it's a bit odd for the manual to describe momentary LUFS measurement but implement it as per-channel, when every loudness meter I've seen measures the combined L+R together. I think a momentary loudness bar that applies to both channels (along with the per-channel peak metering) would be a little less confusing.