Working with 12 edo musicians

Part 1: A friend of mine wants me to play bass with his guitar and vocals live on stage. He only plays in 12 edo and doesn't use barre chords. I've been playing 12 edo bass lines, but I wondered if I could sneak in a few extra notes. The obvious suggestions are 24 edo, or 12 edo with an extra note added a certain amount below each 12 edo note, for example adding notes about 33 cents below 12 edo notes would allow 7/6 just intervals. Could anyone suggest tunings that I could use (of the form 12 edo plus extra notes) that might be particularly effective or fun?

Part 2: He has also said that he would like to play guitar with some of my songs. I usually play guitar and sing and I don't use 12 edo if I can avoid it (I like 12 edo, but everyone else where I play usually uses it and I like variety). Should I try to persuade him to play a non 12 edo guitar (I would have to build it myself, but that's not a problem)? Bearing in mind that he doesn't use barre chords, which tunings should I suggest he plays in? I think he'd probably find pythagorean intonation easiest (It was the first non 12 edo tuning I used because I found it easier to play than most others and I didn't have to recompose my songs), but are there other tunings that might be suitable for a musician used to 12 edo?
On stage I usually perform in Pythagorean intonation, quarter comma meantone, 7 edo or 14 edo, but I think I should extend my range. I use these tunings partly because I find them easy and partly because they have been well received by audiences (I usually play to people used to 12 edo).

--- In MakeMicroMusic@yahoogroups.com, "Mark" <mark.barnes3@...> wrote:
>
> Part 1: A friend of mine wants me to play bass with his guitar and vocals live on stage. He only plays in 12 edo and doesn't use barre chords. I've been playing 12 edo bass lines, but I wondered if I could sneak in a few extra notes. The obvious suggestions are 24 edo, or 12 edo with an extra note added a certain amount below each 12 edo note, for example adding notes about 33 cents below 12 edo notes would allow 7/6 just intervals. Could anyone suggest tunings that I could use (of the form 12 edo plus extra notes) that might be particularly effective or fun?
>

Well, why not take the Jon Catler approach and mix up a few notes from 24-EDO and a few notes from 36-EDO so that you can get 7th and 11th harmonics on each of the 12-tET notes? I think that's a great approach, especially because the additional notes are pretty far from usual 12-tET notes and are the least likely to clash harmonically.

To figure out where to put frets, just think of your open strings (EADG), and then work out which notes each additional fret will actually give you. If you put a quarter-tone fret between the 5th and 6th frets, you get an 11th harmonic for all your open strings, and if you put a -33-cent fret below the 10th fret, you get 7th harmonics for all your open strings. Then you have to add two more quarter-tone frets and two more -33-cent frets, and you'll take care of the remaining 8 notes as well. So a total of 6 additional frets gives you 24 additional notes!

> Part 2: He has also said that he would like to play guitar with some of my songs. I usually play guitar and sing and I don't use 12 edo if I can avoid it (I like 12 edo, but everyone else where I play usually uses it and I like variety). Should I try to persuade him to play a non 12 edo guitar (I would have to build it myself, but that's not a problem)? Bearing in mind that he doesn't use barre chords, which tunings should I suggest he plays in? I think he'd probably find pythagorean intonation easiest (It was the first non 12 edo tuning I used because I found it easier to play than most others and I didn't have to recompose my songs), but are there other tunings that might be suitable for a musician used to 12 edo?
>

15-EDO is my go-to for people accustomed to 12. You can tune all the open strings 480 cents apart from each other and span 2 octaves perfectly. Scales are made dead-simple by this approach, and the 3rds are quite nice (especially the 320-cent minor third). The fifth's a little iffy, but no more so than 14-EDO and most people aren't bothered by it. The only place 15-EDO really gets weird is in the 2nds and 7ths, also--there's two types of "major" 2nd at 160 and 240 cents, and two types of minor 7th at 960 and 1040 cents, but that shouldn't be a problem.

HTH!

-Igs