Thanks, ssri, a custom tag cleared out the confusion indeed.
I'm pretty rigorous when dealing with tags. Almost the entirety of my collection is tagged with
Picard (the official tagger for
MusicBrainz) and I agree with most of their conventions. Great part of my love for MB is because it let me use various tags to customize my collection.
Something similar occurred with the tag PERFORMER (MB included it as <Artist>, but Picard use it to annotate the musician credits (violinist, drummer, bass, orchestra, vocals, chorus, etc.)), but in that case I was able to correct it by modifying the file Configuration.xml in the installation folder, and map it to the <Musician Credits List> Vorbis-tag for MB. I had tried the same in this case, but, for this to work, I had to deal with the PERFORMER problem again, and it doesn't seem that ENSEMBLE can be mapped to any other MB tag in this file.
I have modified Configuration.xml to map other vorbis tags from Picard to MB standards (i.e <Media Type> = MEDIA, <Original Year> = ORIGINALDATE, <Set Subtitle> = DISCSUBTITLE). Maybe we should make a petition in the wishlist forum to have an easy way to map Vorbis tags (since there is no standard for Vorbis).