on these instruments with the standard Fender Mustang bridge (below), solving some of the problems. In addition to the Jazzmaster, Fender used the floating tremolo on the then top-of-the-line Fender Jaguars, released in 1962, and also on the Fender Bass VI, released in 1961. Jaguar and Jazzmasters share the same bridge plate and string saddles, though Jaguar bridges (and the earliest Jazzmaster bridges) have taller legs. The two are functionally interchangeable and replacement parts for each are identical. The Bass VI bridge has a wider plate and longer intonation screws to accommodate bass string intonation, and the saddles have threads cut for larger diameter strings. There have also been a small number of not very notable imitations by other makers, generally without the locking knob. Fender discontinued all floating tremolo models by 1980, but reintroduced both the Jazzmaster and Jaguar first as Japanese models in the mid 1980s, then as American-made reissues in the 1990s. The tremolo-equipped Bass VI was reintroduced as a US Custom Shop model in 2006. An advantage or disadvantage, depending on taste, is string resonance audible at several fret positions where a simple relation exists between the length to the fret and the string length behind the bridge (for instance 48:12 = 4:1). At those positions, a high overtone rises in volume. This becomes clearer with an over-driven guitar sound. The overtone might sound odd, but it still has a harmonic relation to the note, so is not out of tune related to the open string. For staccato playing, it can be annoying. Muting the strings behind the bridge with felt or other material solves the issue. Dynamic Vibrato The Fender Dynamic Vibrato (also colloquially referred to as the Mustang tremolo or Stang trem) was introduced in 1964 on the Fender Mustang, intended as a student model. It was also notably used on the Jagstang, a custom design by Kurt Cobain combining features of the Jaguar and the Mustang. Some late 1960s Mustangs were fitted instead with the floating tremolo, which was promoted by Fender as their premium unit, but later Mustangs returned to the Dynamic Vibrato. The Dynamic Vibrato is still preferred by some lead guitarists above all other designs. It features a floating bridge similar to that of the floating tremolo, but the bridge is integral with the vibrato unit, unlike that of the floating tremolo, which is mounted separately. The strings are controlled