Auditions are coming soon for the 2011 edition of the YouTube Symphony (more information here), and as a service to those looking to audition there are a series of master class videos on the required excerpts presented and performed by principal players of the London Symphony. The full series of brass clips are here, and the horn one is below featuring David Pyatt.
It is a video worth watching but looking at it I think at least in North America many players will be wondering what is that horn David Pyatt is playing? It looks a bit like a descant but it is actually a Paxman Model 33 F/Bb(A-+) compensating double horn (with a stopping valve). In their website they describe it as follows.
The compensating double system predates the first full double horn, and is an ideal instrument for those players who mainly use the Bb horn, but still like to have the F side.
Paxman’s latest compensating double, the Model 33, was designed to meet the requirements of two of London’s top horn players, and has a single storey F/Bb change valve.
The advantages of this are increased responsiveness and a freer blowing horn as a result of less disruption to the airflow on both sides of the instrument. A stopping valve is standard on this instrument.
Compensating doubles do have a very responsive feel with generally a lighter sound. Watching the fingerings you can tell as well that Pyatt follows the approach stated by Paxman—he mainly plays on the B-flat horn but makes use of the F side when needed.
Don’t check out the video just to see the horn, there is more good information there, but if you were wondering this is what a modern compensating double looks like in action and they are in professional use. I have more on compensating doubles in this article.