Several embodiments of medical ultrasound handpieces are described each including a medical ultrasound transducer assembly (444,462,474). An embodiment of a medical ultrasound system (442) is described, wherein the medical ultrasound system includes a medical ultrasound handpiece having a medical ultrasound transducer assembly (444,462,474) and includes an ultrasonically-vibratable medical-treatment instrument (446,466,478) which is attachable to a distal end of the transducer assembly. An embodiment of a medical ultrasound system is described, wherein the medical ultrasound system has a handpiece including a medical ultrasound transducer assembly and including a housing or housing component surrounding the transducer assembly. A method for tuning medical ultrasound handpiece includes machining at least a distal non-threaded portion of an instrument-attachment stud of the transducer assembly to match a measured fundamental frequency to a desired fundamental frequency to within a predetermined limit. A method for making a medical ultrasound transducer assembly determines acceptable gains for gain stages of the transducer assembly.