- - Please visit: Legacy Horn Experience - -
An unexpected benefit of teaching at ASU is that they own a pair of piston valved horns, an early 20th century Hawkes single horn that takes crooks and a Selmer double horn from probably the 1950s.
Having played a good bit on several different piston valved instruments I would say that they do have a faster action speaking generally compared to rotary valves. In the days of single horns piston valves were fairly common, but today they are quite rare.
The best piston valved horn I ever tried (briefly) was a custom double descant horn by McCracken. 
A great horn but clearly one of a kind, with a much more comfortable, slanted action of the valves compared to the ASU instruments.
The question people always wonder is why so few piston valve double horns? I suspect strongly that the main reason is because rotary valves just work better in terms of actually laying out the tubing arrangement for a double horn. The double horn piston valves are exceptionally long, which has several negatives for horn design.
