The J.A. Custom Amadeus Master has excellent response and tone. With a 3 part zigzag slide system the Amadeus is by far the loudest 12 hole chromatic harmonica on the market. The 3 part slide mechanism, gives the harmonica a much better slide action, but it also gives the player better response and dynamics. Out-of-the-box chromatics are well known to have response issues on hole 10, 11, and 12, but on the Master model all holes and reeds are fully playable with equal response. The valves are modified for a much smoother action. It is assembled with screws for easy maintenance and features its own unique serial number. Are you looking for a harmonica with incredible volume, perfect response and a smooth slide action, then you do not have to look any further!