[Dixielandjazz] 'Nuther dumb question

[Craig I. Johnson]

John asks: What I'm
> wondering is how trumpet and cornet differ from one another, and why might
> one prefer one instrument over the other? Anyone care to jump in?
I'll jump in. 
Some  instruments are essentiall cylindrical throughout the length of the horn.
E.g Clarinet, flute, oboe. 
Others are conical e.g., Saxophone., French horn, I believe.

The difference theoretically between a cornet and a trumpet is that
the trumpet is conical back to the valves or at least the first bend after the
bell to just after the valves. After that the tubing is a cylinder. 
Due to its method of play with a slide, the trombone have to be similarly constructed.

The Cornet is in theoretical definition, conical all the way back. As this can cause 
troubles with things like tuning slides, which would not move if the tubing were really 
all conical, there is a compromise made. So one can say that the cornet is simply conical 
much further back than the trumpet. I'm not sure of the exact point of departure from the cone.

Why would one choose one over the other?
The trumpet (as far as I personally am concerned has a more brilliant tone.
The cornet, like the flugelhorn, has a much broader tone. In my mind that can also be
also a funkier tone and I like it far better for trad jazz etc. The trumpet being
more brilliant stands out more in a large orchestra (be it classical or jazz)
 and thus for many is more suitable in that environment. However that is not
a given. Warren Vache' - even when he was playing first chair for Benny Goodman
played a cornet. I believe he recently switched to trumpet for a short while but
prefered the cornet and went back to it for all the styles of jazz which he plays.
(Actually, regardless of style, I play cornet or flugelhorn for all jazz. 
Haven't touched my beautiful Selmer trumpet in years. - but no, it is not for sale.
I've had it since high school in the mid 50s.)

Regards,
Craig Johnson
Cornet, "The Maine Street Paraders"
Kennebunk Maine.