Admittedly, the history of the clarinet is extremely long and I'm sure that you could find a straight alto clarinet or three in there, but I can't recall ever seeing one. I'm fairly sure I've seen at least one from about the time A. Sax was playing with bass clarinet design that had the curve-ish neck and a straight bell, but not a full-on straight horn like a standard Bb clarinet.
This is an example of what I was referring to. http://www.ebay.com/itm/Conn-Direct...aultDomain_0&hash=item417834d524#ht_215wt_936 It is an E-Bay listing. I know that not all E-Bay listings are posted by knowledgeable people, but this one had the air of someone that knew their instrument, especially the reference to, "This is a 5 ring, 19 key instrument." Personally, I wouldn't know a five ring clarinet from a three ring circus. I am in the process of buying a Bb clarinet and I ran across this one. I am just a little confused by it and a couple of others. While we are at it, what is a Bb clarinet called? Is it a tenor or just a Bb?
I have seen G clarinets (simple system, Far Eastern European origin) listed as an alto clarinet, so it's always possible that someone might blunder into something and mislabel it.
I keep waiting for Selmer and Buffet to drop the alto from their lines. I have always wondered how many of them they sell in a year, and how many don't go to high schools of that total. It would make for a nice barometer to use to follow the demise of the things.
Still (and being absolutely fair, even about an instrument that I despise) there are a couple of legitimate English symphonic works that call for the alto. Apollo And The Seaman is the only one that I can recall - it features a couple of extended solo passages for the horn (in conjunction with a vocal part - another wacky English composer affectation.
As they do have a rather "unique" voice, you would think that there would have been more use of them, just for novelty's sake alone. Does anyone have knowledge of any other non-English composer's (other than from the period 1900-1930) serious orchestral works that have a published alto part in them?
The most recent orchestration book that I have skimmed through didn't have a section on them. Of course, this was the same book that made the blanket statement that bass clarinets in A have never been manufactured, so it may just be that the author was another one of those piano players that persist in writing parts for the Boehm instrument that mandate sliding the little fingers in sixteenth note passages…