All 12 chromatic tones, and similar range to a sax.?
Keep in mind that this is intended more to be a "starter" instrument to teach the rudiments of playing the saxophone.
I don't think you'll find anyone playing this professionally. While the Clarineo and Nuvo flute could be considered "real" instruments, this is a step under that, and a step above the DooD and TooT.
It's got a
much more limited range than a real sax, and even less than a recorder. You can in theory play from middle C (C5) chromatically up to G6. In practice, I find notes above E6 to be difficult.
So you're going to be limited to songs that fall within a vocal range, and don't go below middle C. There's a whole lot of music that fits that category... and a whole lot that doesn't.
It is fully chromatic, with keys for all the holes. But it's pretty simplified relative to a real sax.
On the right hand, the C, D and F keys cover two holes - one hole covered completely by the key, the other with a hole above where you place your finger, sort of like an open-holed flute. When you place your finger over the hole, both holes are closed and you get the natural note. When you close the key without covering the hole under the key, only one of the two holes is closed, and you get the sharped note (C#, D# or F#).
There's a G# key on your right hand. But there's no key for the Bb - you use the same "forked" fingering you would with a recorder, by covering the B and G holes.
If you've played recorder or any wind instrument, you'll know the fingering.
Is it easier to play in tune and by how much?
It's a reed instrument, so differing amounts of pressure
will give different pitches.
Is it is easier to blow and by how much?
I don't have much experience with "real" saxes. But I'd say that it's easier to blow than the clarinet and Xaphoon. Then again, I played on those first before playing with the jSax.
It comes with a plastic reed, so you can just pick it up and blow without having to wet it. It's pretty easy to blow.
The downside is that it's a plastic reed. But it works fine for me.
Legere has a
synthetic reed called the viib made specifically for the Nuvo instruments. I haven't tried it yet, but it's a step up if you want to go that direction.
Is it easier to physically play the notes?
Well, it takes no effort to close the keys, and the instrument weighs just about nothing. For my hands, the reach is also comfortable. I consider a tenor recorder a bit of a stretch, and the Xaphoon to be uncomfortable. in terms of key placement, it's closer to the feel of an EWI.
For me, this is the sort of instrument that I've been looking for for years. It's by no means a "pro" instrument, but it's not a "toy", either.
Now if only Nuvo would come up with an oboe, I'd be in heaven.

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