What is the story behind the shape of the bell on an English Horn?
But first, a quick look at the clarinet family for a comparison.
The standard clarinet (in Bb or A) has normal looking "bell-shaped" bell (some kind of rotated exponential curve).
The Clarinet's larger brother/sister the basset horn (in F) has a bell that comes off at an upturned angle, it's usually made of metal rather than wood. I can understand some reasoning behind this – if the bell continued straight down the instrument would be too tall, and pointed straight into the ground. So the instrument designers have curved it upward to face the audience. To get the curve right, it is easier to make it from metal. The bell is still basically bell-shaped.
The oboe family is a different.
The standard oboe (in C) has a stumpy little bell with not too much flair to it at all (no offence).
A larger member of the oboe family the english horn / cor anglais (in F) has a "bell" that is very different – it's onion-shaped.
Why don't the oboe and the english horn have a similar shape bell?
How does this effect the sound that each instrument produces?
What would an oboe with an onion-shaped bell sound like?
and What would an english horn with a bell-shaped bell sound like?
(and why is this presumably undesirable?)