1990 Philip Kubicki Ex Factor Bass – Includes Original Hardshell Case – Used Very Good
Philip Kubicki's design career began at Fender in 1964, where he worked under Roger Rossmeisl in the R&D division and was directly responsible for some of the most significant prototypes in the company's history — the Telecaster Thinline, the first rosewood Telecaster built for George Harrison, and the last guitar Fender ever built for Jimi Hendrix. When Kubicki left Fender in 1973 to start his own venture, he eventually turned his attention toward solving a problem that had bothered bass players for decades — neck dive, headstock-heavy balance, and the lack of true ergonomic thought in bass design. The result was the Factor bass, introduced in 1985 and built entirely around the principle of human factors engineering. The Ex Factor variant adds a clever and genuinely useful feature: an integrated drop-D lever built into the headless tuning module that lets a player drop the low E string to D almost instantaneously, without retuning or transposing — a detail that made the Ex Factor a favorite of players who needed that flexibility on the fly. By the late 1980s demand for Kubicki's basses had grown so significantly that he entered into a licensing agreement with Fender, and from 1989 to 1991 Factor and Ex Factor basses were built at the Fender Custom Shop in Corona, California. This example, dated September 1990 by its serial number, comes from that period. The solid maple body with its distinctive offset waist houses the patented bridge/tuner module at the tail end of the bass rather than a conventional headstock, redistributing weight so the instrument balances naturally without any tendency toward neck dive. The laminated hard rock maple neck is bolted on for stability, with an ebony fingerboard, 7.5-inch radius, and Kubicki's signature side-dash position markers rather than conventional fretboard inlays. Two Kubicki-designed humcancelling pickups feed a 9-volt active preamp — the configuration most commonly found on Fender Custom Shop-built examples from this era — controlled through stacked volume/pan and treble/bass pots along with a 4-position rotary switch offering active, passive, and standby modes. The result is a genuinely unique-sounding and unique-feeling bass that remains unlike anything else on the market, decades after its introduction.
This one has clearly been played and loved — there is noticeable surface finish swirling throughout and one good-sized finish chip in the cutaway area, all shown in the photos. It plays great, with minimal fret wear, a straight neck, and a smoothly functioning truss rod and drop-D lever. Currently strung with black tapewound strings, which suit the bass's warm, ergonomic character beautifully. The original hardshell case is in good shape with some expected wear and tear.
- Make: Philip Kubicki
- Model: Ex Factor
- Era: Fender Custom Shop licensed production (1989-1991)
- Serial number: 2809 09 90 (September 1990)
- Country of origin: USA (Fender Custom Shop, Corona, CA)
- Body: Solid maple, offset waist
- Finish: Black, gloss
- Neck: Laminated hard rock maple, bolt-on
- Fingerboard: Ebony, side-dash position markers
- Fingerboard radius: 7.5"
- Scale length: 32" (36" with drop-D extension engaged)
- Frets: 23, plus extra frets on headstock for drop-D extension, minimal wear
- Nut: Phenolic, 1-17/32"
- Pickups: 2 Kubicki Hum-cancelling
- Preamp: 9-volt active (Fender Custom Shop era electronics)
- Controls: Stacked volume/pan, stacked treble/bass boost, 4-position rotary switch (passive, active flat, active with mid boost, standby)
- Bridge: Kubicki patented body-mounted bridge/tuner module
- Hardware: Black
- Strings: Black tapewound (currently installed)
- Modifications: None
- Condition: Used Very Good – noticeable finish swirling throughout, one good-sized finish chip in cutaway area, minimal fret wear, plays great
- Includes: Original hardshell case (good shape, some wear and tear)
Ships carefully packed and insured for full value. International buyers are welcome — please contact us for a shipping quote before purchasing.
About Mill River Music
Mill River Music is an independent, human-powered music shop located in downtown Northampton, MA, run by a team of players, enthusiasts, and certified repair technicians. Every piece of used gear we sell is personally inspected, tested, and set up before it ships — we don't list it until we'd be happy to play it ourselves.
As Martin and Taylor certified techs, we hold our guitar work to a high standard, and we're committed to full transparency about the condition of everything we sell. No surprises.
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