How do you take Stereo audio and convert it to Mono?

I have an interview clip that I shot with my iPhone in which I interviewed someone. The audio that comes out of the iPhone is stereo. But I want to convert the audio to pure mono. Or to be more specific, SUMMED MONO, where the information in the left channel is panned to the center and the information in the right channel is panned to the center and both sides are SUMMED in the center to create mono.

I don't see an obvious way to do this in Resolve. Could someone kindly enlighten me as to how to do this?

Thanks in advance.

Randy Brown

Instantiate the Fairlight Stereo Fixer AFX on the source Track or Clip and select the Mono Format.

Alternatively, in the Fairlight Panner reduce the Spread control from Full to Point if the source is on a stereo Track but be aware of the small amplitude increase.

It may be preferable to rather use Clip Attributes to select the preferred embedded source channel or use the Fairlight Stereo Fixer AFX to audition source channels individually with the Left Only or Right Only Format options.

If the stereo recording is actually from two separate mics on your phone, I would use the clip attributes to select only one channel to use as the mono source. Summing two separate mics could introduce phasing/combing artifacts.

A straightforward way (to actually keep it summed, and not just solo the left or right) would be to just change the main bus format to mono:

Fairlight Menu >> "Bus Format" >> Then change Bus1 to Mono (if that is your main bus—there is always at least one by default)

Any track, be it Stereo, or whatever, will end up eventually as a summed mono because it is being piped into the Main Bus1. Then just make sure your render settings for audio are also mono.

Then, the only thing to consider is the Pan Law. If "Panning" is toggled on for the track (even if you haven't adjusted it.. it's literally just toglled "on"), then you will have to increase the volume of the main Bus by 3db to compensate, if not, then leave as is to keep the volume the same as original.

Let me remark that there's excellent (and free!) training material like "The Fairlight Audio Guide to DaVinci
Resolve 18" that handles such. Like on page 72 of the PDF: "For this exercise, you’ll change the A1 track format from Stereo to Mono."

I would have just suggested right clicking on the audio track header in the timeline and selecting "change track type to mono."

It seems the simplest. Am I missing something?

Changing the Track Format does not result in a downmix or summing of the source, but rather a single channel mapping (which may be preferable, but not necessarily what is required by the thread starter).