As a lifelong classical player, I have at times dabbled in jazz. Have played the Shaw Concerto a dozen times and done some dixieland and a bit of improv at times. I admit I never gave double lip a decent try-- like circular breathing. But I can't see how it would be comfortable. I don't know if angle of the clarinet has much to do with it. I basically have "normal" angles-- you know, some variations when soloing, etc. I think the high angle may just be for show?

OK,  I've got a couple more numbers for your list. First is 14293 which is an Artist's Model A clarinet. It came with two barrels, each of which is clearly labelled Artist's Model A. One of the barrels is marked USN. I can find no other marking on the instrument or the second barrel. The serial number is stamped at the bottom of both the upper and lower joints. The clarinet has the smaller "Artist" engraved below the New York stamp.

The second instrument is number 17509. This is a Bb clarinet with one barrel. The "Artist" on this one is larger and engraved just below the eagle. The serial number on the upper joint is stamped vertically between the second and third posts of the right hand trill keys. The serial number on the lower section is also stamped vertically below the forked B/F# post and under the right hand little finger F#/C# key.

My experience is as a classical style player of about 65 years. I'm unaware of any classical players who use a double embouchure. I'm 99% sure that Pete Fountain used the "traditional" embouchure.

Bass recorders are in the F, but read C music. The F recorders use a different set of fingerings than the C recorder. The C instrument's fingerings are similar to flute or sax. The F instruments are similar to the lower register of a clarinet.

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