I currently play on the Yamaha EC cut headjoint; it's good! I always get a clear tone on it, even in fast technical pieces. But it is a tad bit hard to play softly and in tune with a good tone on that headjoint. This headjoint blends in quite well in ensembles!
I would also try the Jack Moore and Burkart headjoints, but I'm not sure if they'll fit perfectly. If the headjoint is too loose, just put a tiny strip of packaging tape on the tenon of the headjoint so that it'll fit.
If the fit of the headjoint is too big, then just go to a music store and ask if you can borrow one of their flute bodies to test out the headjoint.
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Just in case; if you plan on getting a gold lip plate, then know that gold PLATED lip plates do wear off quite fast, resulting in some of the lip plate being gold, and some of it being silver again. Looks a bit strange. If you can, get the gold lip plate to be solid gold.
if you like the headjoint and are going to buy it, you can shave some of the silver off (must have a tech do)
I know people who use the Burkart headjoint on Yamaha flutes. They sound so much crisper (but still has that dark sound) than any Yamaha headjoint I've played on... I think they will fit. I think a Brannen headjoint may be a bit too "muddy" for a Yamaha flute, but you'd have to try for yourself.
If you can get your hands on either a Burkart M2 or a Powell Philharmonic, TRY!!!!! I know they will fit (probably be a bit small)
Most headjoints can be fitted to a flute body, which a good specialist should be able to advise you on.
But why can you only try four? That sounds rather strange. Do they send them to you to try or something? I wouldn't stop trying until I found the one that I was most comfortable with. You shouldn't have to limit yourself to just 4, you have no real way of knowing from that list which would be the best 4 to try.
I play with a bog standard yamaha body, and a powell 1200 headjoint, and I enjoy playing it, but each person is unique.
I have one of their headjoints and I find it to be well worth the money. But, it is a fairly "wooden/dark" sound compared to the Yamaha headjoint, as expected.
Most makers are familiar with the specs on the various Yamaha flutes, so they can easily make a headjoint that fits it properly.
so if fluteworld will ship them to you, they need to fit - at least for the trial's sake. But you can send them all back and get another 4 you don't like any of them I presume?
Is there nowhere you can go in person to a specialist shop and try some there? Or are you quite remote?
i like Flute World. They're a nice company with (mostly) nice people. And they're very helpful.
If you're trying new, I would HIGHLY recommend you call and ask to try the Powell Aurumite 14k headjoint they have right now. I almost bought it when I was playing on it, and I just bought a new headjoint. It was THAT awesome!!!!