The GMP 400 represents the top range in headphone technology:  Uncompromising sound reproduction with crystal clear trebles, rich details in the mid-range and precise dynamic response in the bass reproduction.  The technical features are also very impressive:  Sandwich diaphragm, copper plated aluminium voice coils, ear cups with cardamatic suspension, ear pads made of a top-quality soft velvet and a gold plated Multi-jack-plug.  Many recording engineers' favorite headphone!