I am asking about this because of a question that came up elsewhere, and I don’t feel I got a clear response about this anywhere, and the manual is deeply unsatisfactory on this topic (unless I missed something).
The question is what we are supposed to see when routing stereo into mono, considering default downmix settings(?) and pan law(?).
To recap where we left off:
Ok, the above is clear enough, but not when I measure it. To test I did the following:
- Create mono output.
- Create stereo audio track, insert test generator on it, set it to sine @ -9dBFS.
- Route stereo audio track to mono output.
- Set metering to “input”.
Now, here’s what I see on the mono output channel meter with respective pan-laws;
pan law / input
So, if pan law has nothing to do with going from stereo to mono, and only a default 6dB downmix attenuation applies, then why are we seeing a different value at the input of the output channel?
Can people here confirm that the above is what they see as well, and can someone please explain the behavior?
It seems to me as if pan law indeed does change what happens to a signal as it leaves a stereo channel and goes into a mono channel, and it’s not a downmix preset that’s used (or maybe correctly - the pan law becomes the downmix default for the project). It’s as if pan law is applied to the independent left/right channels within the stereo channel.
For reference, from the Nuendo 6 manual:
Stereo Pan Law
In the Project Setup dialog, in the “Stereo Pan Law” pop-up menu you can select one of several pan modes. These modes are required for power compensation. Without power compensation, the power of the sum of the left and right side is higher (louder) if a channel is panned center than if it is panned left or right.
To remedy this, the “Stereo Pan Law” setting allows you to attenuate signals panned center by -6, -4.5, or -3 dB. Selecting the 0 dB option turns off constant-power panning. Experiment with the modes to see which fits best. You can also select “Equal Power” on this pop-up menu, which means that the power of the signal remains the same regardless of the pan setting.
This changed and now Nuendo 8’s manual states:
Stereo Pan Law
If you pan a channel left or right, the sum of the left and right side is higher (louder), than if this channel is panned center. These modes allow you to attenuate signals panned center. 0 dB turns off constant-power panning. Equal Power means that the power of the signal remains the same regardless of the pan setting.