OneLicense.net is a clearinghouse for churches which want to get licenses to reprint hymns, songs, and anthems in their bulletins or project them on screens. Like Harry Fox for recordings, OneLicense.net allows one-stop shopping as a convenience to publishers and musicians alike.
Their latest initiative is the "Practice Track License", which allows you to make practice CDs or MP3s to help your choir members learn the music. If you buy this license, you can make copies of publishers' demo recordings, commercial CDs (if the CD was produced by a publisher participating in the program), or make your own recordings. Presumably this includes MIDI files, although their website doesn't mention those specifically.
There's a significant question whether it's even necessary to get copyright permission to make a practice recording (except for copying a commercial CD). Publishers' demo recordings are essentially advertisement for the music. A MIDI file or a recording of Joe Conductor singing the tenor part is obviously not a recording intended to be listened to for enjoyment. But copyright law doesn't address MIDI files or other such practice recordings directly, nor has there been any specific court precedent.
I've never heard of a publisher suing somebody for distributing MIDI files, and there are a number of websites which offer thousands of MIDI files quite openly. Beyond the uncertainty of the applicable law, I have to assume that it's a strategic decision on the part of publishers, who figure they're selling more copies of their music (and collecting performance royalties) if people have the tools to learn it.
But maybe these church publishers figure that lots of choirs are learning the music by rote, and since church services are exempt from performance licensing, their only chance to get some income from these churches is to collect on the practice CDs. And I have to say from an ethical standpoint, they are probably right if groups are using these recordings to avoid purchase of the music. (Avoiding purchase is my general ethical yardstick for copyright gray areas. For example, copying a page to avoid a tricky page turn is obviously not motivated by the desire to avoid purchase.) It's a little different, in my opinion, from somebody who gives their singers MIDI files of Ceremony of Carols as a supplement to the musical score. It's only fair that composers get some kind of compensation when churches sing their anthems.
But the price is a little steep. For $75, you get 100 "credits" which allow you to make one copy of one recording of one song (the music in a whole mass or liturgical services counts as 5 credits). That's 75 cents per rehearsal track, far more than the mechanical license for making a commercial recording. And it's a bit strange that it's so high, since OneLicense's prices for other things are pretty reasonable; for example, a church with a weekly attendance of 300 only spends $190 for unlimited reprint rights for an entire year. But their choir of 20 singers would burn up that much every couple of months just on rehearsal CDs (or MP3s). It would make a lot more sense to have an annual unlimited license the same way they do for the hymn texts.
What would make even more sense is if Congress amended the copyright law to clarify when rehearsal recordings are permitted. MIDI files used to supplement purchased copies should be specifically exempted from copyright restrictions. But copyright lawyers seem more focused on helping record companies follow MP3s into children's bedrooms than helping composers and performers find an equitable balance between their respective needs.