Simple arithmetic applied to musical terminology demands that if you add up four trombonists, the sum should be called a trombone quartet. So why is it that I have trouble bringing myself to call Guidonian Hand a trombone quartet?...I don't know, but I can say that Guidonian Hand is simply Guidonian Hand and nothing else because the sum of these four extraordinary musicians--Mark Broschinsky, William Lang, Matt Melore, and James Rogers--equals something beyond what the term 'trombone quartet' could muster in my imagination. Everyone can hear this musical alchemy in their performances...As in any great performing ensemble, each member is in his own way the center of the group while at the same time no one is the center. That's the magic of the sum of the parts. Each person brings something unique to the rehearsal besides his abilities on the trombone. When the four personalities have merged, when what each player brings has been subsumed in the whole, there occurs that something which is always greater than the sum of its parts, the magic of great ensemble playing. That is what one hears at a Guidonian Hand performance.
--J. Mark Stambaugh, Composition Faculty Manhattan School of Music