Abstract: An acoustic stringed instrument includes a multi-tiered neck-body joint that removably secures the neck to the body, provides a superior structural and acoustical coupling and enables an expanded treble cutaway that provides improved access to higher regions of the neck and elimination of the neck heel and other external structures in the vicinity of the neck joint.

Abstract: A guitar neck is formed with a protruding trapezoidal heel which extends into a pocket formed at the neck end of the body. The tendency of the strings to bend the neck is counteracted by a truss rod assembly which is positioned in a contoured channel formed in the neck beneath the fingerboard. The assembly has a threaded stainless steel rod which extends through an aluminum U-channel, with one end extending beyond the U-channel beneath and adjacent the first fret of the fingerboard, where it is fixed to the U-channel, and the other end extending out of the U-channel adjacent the neck-body joint, where an adjustable hex nut is threaded on the rod which bears on a washer. Two cylindrical spacers are fixed to the rod within the U-channel at positions upward of the neck joint which serve to hold the rod in the center of the U-channel between the U-channel legs, and also spaced outwardly from the base of the U-channel to thereby cause the rod to bow away from the base into the contoured channel in the neck.

Abstract: A guitar neck is formed with a protruding trapezoidal heel which extends into a pocket formed at the neck end of the body. Motion of the heel within the pocket is limited by the sides of the pocket, and by a lip which protrudes from the pocket floor to engage with the neck upwardly of the neck heel.