Upgrade euphoniums feature a 4th Valve that increases fingering options and improves intonation on many valve combinations. 

Hand-lapping of pistons and slides ensures a perfect fit and seal between the pistons, casings, and slide parts. 

Larger bore and bell size encourage greater use of air, resulting in a much bigger sound.

Conical tubing provides a richer, darker sound.

Different plating options like gold valve caps/buttons with decorative finger buttons give the horn a special, elegant look and may subtly impact the tone color of the instrument.