tone than alder. By the mid-1970s, the combination of 4" pickup spacing and the use of heavier ash bodies with maple fingerboards combined to produce a notably brighter tone than that produced by Jazz basses from the 60s. American Standard Jazz Basses produced between 1989 and mid-1994 featured a larger body shape, a 'curved' neck plate set into a chambered pocket for greater sustain and a 22-fret neck, similar to that of a Precision Bass Plus, with a standard vintage-style top-load bridge, two separate volumes and a master TBX tone circuit. Usually known as "Boner" Jazz Basses, these early American Standard models (designed by George Blanda, who was Fender's senior R&D engineer during that period) were discontinued in 1994 and shouldn't be confused with the Fender Jazz Bass Plus, which has the same 22-fret neck design, but utilizes a different (downsized) body styling, Lace Sensor pickups, Schaller "Elite" fine-tuner bridge on the four-string model or Gotoh Hardware high-mass bridge on the 5-string model, and Phil Kubicki-designed active electronics. Unlike the Fender Precision Bass Plus, which had an optional maple neck, the Boner Jazz Bass was offered only with a rosewood fingerboard. The Jazz Plus Bass was available with an alder body and the option of a natural-finish ash body on the four-string model for a $100 upcharge, either a maple or rosewood fretboard on the four-string and pau ferro (an exotic hardwood whose tone is brighter than rosewood yet warmer than ebony) on the five-string. The Jazz Plus debuted in 1989 (the five-string model was released in 1990), but was discontinued in 1994 and replaced by the USA Deluxe Series Jazz Bass the following year. A fourth push button control is available on American-made Jazz Basses produced between mid-2003 until 2008. Known as the "S-1 Switch", this feature allows the pickups to operate in standard, parallel wiring, or alternatively in series wiring when the switch is depressed. While in series, both pickups function as a single unit with one volume control, giving the Jazz Bass a sound more similar to the Precision Bass. The two pickups are built to be opposite from each other in both magnetic polarity and electrical phase, so that when heard together, hum is cancelled—the humbucking effect. The Highway One Jazz Bass is a moderately priced American-made bass introduced in 2003, featuring a Leo Quan BadAss II bridge with grooved saddles, Posiflex graphite neck support rods,