Yamaha YTR-6335RC Bb TrumpetProfessional Bb Trumpets. (Medium large bore). Completely developed at the Yamaha Atelier in Hamburg, the new Yamaha Commercial Trumpet, has been designed for players who play in a variety of different musical settings. Easy and quick precise response The bell connection ferule with gap, together with a reversed tuning slide and curled water key springs have allowed us to create the Commercial trumpets signature easy, quick and precise response.