I'm looking for a method of moving FLAC album-gain values into the FLAC track-gain field.
Background: I've an extensive classical music collection tagged by MP3Tag (thank you, Florian) which I used to listen to through Foobar2000, and remotely from my NAS on Roku Soundbridges.
I recently upgraded to a couple of Sonos units which, on-the-whole, truly delight me. Only challenge: the Sonos implementation of RG is partial. I understand that Sonos reads only the FLAC track-gain fields, and for classical music this largely defeats the purpose. (It uses iTunes fields for other formats).
I've created an action that invokes $rg2sc to move the album-gain to the COMMENT ITUNNORM field on mp3s, and the ITUNNORM field on aacs, which Sonos understands for these encodings.
How can I get FLAC album-gain into the track-gain field? Can I simply copy %replaygain_album_gain% to %replaygain_track_gain% in an action?