An idea of mine. I have a spare clarinet mouthpiece, and a couple of recorders. I was wondering how hard it is to fit said mouthpiece onto a recorder (soprano or alto)
Sure you could butcher something to fit, but probably pointless when the recorder bore, hole spacings etc. won’t work right with it.
I think you should find out for yourself and then report back to us.
On a technical note: If all else fails, there’s always duct tape.
The Reed Trombone, mixing brass and woodwind mouthpieces
The Tromboon! Bassoon and Trombone mashup
Plenty of tape in use here, but take heed of Trent Hamilton when he says at the end of the first of these videos:
‘So I guess after all these experiments the conclusion that we must draw is that, when you’re playing one of these instruments, whether it be a baritone or a trombone or a sax or a clarinet or whatever, the mouthpiece that you should best use just so happens to be the one that they’ve been using all along.’
Those were quite interesting. However a chalumeau does use a clarinet mouthpiece. And is sold as such I believe.
A chalumeau on just flutes, with clarinet mp
And a recorder body is not a chalumeau body, which is constructed to accommodate and profit from a clarinet mouthpiece in every way. Likewise, a recorder body is built to suit its own proper mouthpiece. An instrument is built as a whole unit, from tip to tail. A big mistake is to look at a woodwind and say, “It’s just a tube with holes; can’t be that big of a deal.” That’s why I think you should try it yourself instead of asking us, because it’s already evident you’re not interested in lending our input any weight anyway. So go ahead, and just do it yourself and see. Direct experience will serve you well enough.
Most instrument components are not functionally interchangeable except to get an unsatisfying oddity at best. But don’t take our word for it; I say do it, and discover it for yourself. Then come back to us with your findings.
I knew you’d say that. But see also what I said in my first reply and what Nanohedron’s just reiterated!
The chalumeau has a cylindrical (or nearly cylindrical) bore. The baroque recorder has a complex conical (reverse-tapered) bore which I’m guessing also to be narrower at the bell end at least. They’re chalk and cheese.
https://www.sansluthier.net/es/viento-castellano/clarinetes-de-bolsillo/clariphone/clariphone. 2 1/2 octave range…probably the best you’ll see in a pocket clarinet. Just a few extra holes to keep track of.
Hmm the bore, of course! Whereas a recorder has a reverse conical bore, giving it its unique tone.
I have confirmation, it doesn’t work. Tho bear in mind I am using a clarinet barrel so that the mouthpiece will mate to the recorder (Yamaha Alto), and with a chalumeau the mouthpiece is sunk into the body, so there is some distance between the mouthpiece and body here.
I’m not an instrument maker … but it seems to me that there must be a lot more going on to give a recorder “its unique tone” than just having a conical bore. Otherwise, how come conical bore whistles don’t sound like recorders?
Something to do with intonation in the 2nd 8ve, IIRC from past discussions. In the case of our typical wooden flutes, a reverse conical bore also makes for a shorter operating length; without it we wouldn’t be able to meet, at least comfortably if at all, the hand stretch needed on cylindrical bore simple-system D flutes.
As I understand it, almost entirely due to profiling at the mouthpiece: the windway, window, fipple, splitting edge, … A recorder with a cylindrical bore would still sound mostly like a recorder.
The first problem with sticking a reed head on a recorder body would be intonation: none of the notes would be in tune, with each other or anything else. Even the second register would be out of tune with the corresponding notes in the first register.
While it wasn’t going to work anyway, I can tell you (having just watched your video) that there’s no real distance between mouthpiece and body here when the combined length of your clarinet mouthpiece and barrel could still be shorter than the sounding length of your recorder with its normal head. But don’t expect matching these to make it better because they still don’t belong together!
I think AuLoS303 should find that out for himself, too, just to confirm the point. And besides, I wanna see duct tape. 
Recorders have a reverse conical bore. Even so it would be interesting to see how a recorder with a straight bore would sound. Whistle-like?
The point is that masses and masses of whistles also have a conical bore. But they don’t sound like recorders - they sound like whistles. And, as has been pointed out above by someone more knowledgeable than me, it’s not the bore (or, at any rate, not principally the bore) that creates the recorder-like sound of a recorder.
No! Do you know why I said the baroque recorder has a complex conical (reverse-tapered) bore? Have you tried Googling recorder cylindrical bore? No, didn’t think so…
Not in all cases.
Mr. Hamilton clearly didn’t do his homework
Maybe he should shut his trap and open his ears
https://www.youtube.com/watch?v=NMmjh4qkEZY
Scroll to 3:25
https://www.youtube.com/watch?v=tQzDud85t1E
This one is more like old Trent,
but much more musical.
Mats Gustafsson on fluteophone
Scroll to 37:50
https://www.youtube.com/watch?v=QQ5hMM6LOE8