Mick, thanks for your explanations. If I understand correctly, also your post to that other thread of 02 May 13 - 06:41 PM, the main problem is that the programmers cannot agree on a standard. If they could, it would be the ABC standard, regardless of what others write. (Chris Walshaw, the authors of those "proposals", and most other members of "abcusers" must probably be regarded as an "advisory board".) Even abcm2ps and abc2midi, often found bundled, differ in their interpretation of the standard, and each version of abcm2ps differs from its predecessors (let alone "fork-offs", as perhaps used in concertina.net). I doubt that anybody can enforce "an enforced standard" if the influential programmers don't bother. The reasons why they didn't bother so far still escape me; it may be a matter of policy (but why?, and why don't the users seem to protest?) or just lack of consciousness; in the latter case there is hope for improvement.

All we can do at Mudcat is to proclaim a "Mudcat ABC Standard" in due time. It should

• include support of multivoice tunes, particularly SATB choral music in modern clefs,
• be supported by some free software for producing sheet music,
• be supported by some free software for producing sound and MIDI files,
• be supported by some free software for conversion to MusicXML,
• - all these for Windows, Mac, and Linux,
• and never change in the future, except for extensions,

for which the best idea is to refer to a subset of a published standard officially accepted by all those programmers.

We must wait for relevant news from the principal programmers; whoever hears any should please inform us. Until then, ABC 2.1 as implemented in new versions of abcm2ps (presumably the engine of mandolintab.net), minus the "volatile" parts, can serve as the "Provisional Mudcat ABC Standard".