Questions for (advanced) flautists

Hello

I have to compose a duo for cello and flute for my course, which is eventually going to be performed by members of a professional contemporary music ensemble. The actual musical content is all worked out, but I have some questions about extended techniques and flute characteristic in general:

1. Regarding multiphonics: Seeing as no two players or instruments are the same, would it be better to write something like 'loud, piercing multiphonic' or 'soft, consonant multiphonic' above a blank note stick, rather than notate a specific multiphonic which some players may have difficultly producing?

2. Do multiphonics require more breath than a single note of the same duration? If you have to take a breath, can the flautist find the same multiphonic again quickly?

3. Can multiphonics be used with dynamics, namely a change from very loud to very soft?

4. Can key slaps be performed as fast as normal fingering?

5.Are there any tremolos of intervals greater than a fifth that are particularly hard to perform? What is the best register to perform trills and tremolos in? I know about the difficulties in trilling at the bottom of the flute's compass.

Thank you

Really good questions! It would be wonderful if more composers asked about issues like this before giving out unplayable pieces. Thank you for that :) All right:

1. It's always better, when using multiphonics, to pick a specific multiphonic and write the fingering for it above the note that needs it - since multiphonics are (comparatively rare) in flute music, it's not often that you come across the same one twice, so it's very very helpful to know how to finger it. Don't worry about players having trouble producing it; it's a negligible worry compared to how to GET the multiphonic that you want.

2. It depends on the multiphonic, so there's no real rule - I'd tend to keep the durations normal note length, as even with practice it can sometimes, on a delicately balanced multiphonic, be hard to find again consistently. Don't worry about that, though - more important is that your flutist has a lot of time to practice the notes so they know that they won't crack.

3. Again, with lots of practice (depending on how hard the multiphonic is), but I wouldn't go too crazy.

4. For key slaps all the fingers generally have to move for every note, so key slaps are very very impractical at high speeds.

5. Actually, a lot of tremolos smaller than a fifth can also be quite hard; it really depends on what notes you're going back and forth on. Definitely stay out of trilling low if you can help it, but for other tremolos there are a number of trick fingerings, going (practically speaking) up to two Ds above the staff. You can either consult a fingering book, a flutist, or message me if you have specific tremolos in mind.

Thank you very much for your advice. I happen to live with a flautist, who lent me a book of advanced technique studies but said she wasn't advanced enough to advise me on anything specific. What I've done with the multiphonics I've written is to supply a fingering chart as an appendix to the score, and then put a little letter by the multiphonic in the score (indicating two or three pitches of it) which refers to the chart. There's a wonderful site called The Virtual Flute which allows you to find fingerings and multiphonics as well as having a good explanation of extended techniques - very helpful. My piece is getting performed in a workshop a few weeks before it needs to be submitted, so I will get feedback from the pros then.