Kala Brand Music Co. is based in Petaluma, California, and the U-Bass is the company's compact acoustic-electric bass built around soft polyurethane strings. The RMBL-FS Rumbler is the fretted version, with a laminate mahogany top, back and sides, a mahogany neck, a rosewood fingerboard and bridge, 16 frets, black binding and a satin finish. It carries a Graph Tech TUSQ nut and Aquila Silver Rumbler strings, and the electronics are a Shadow pickup system with a built-in tuner. Kala lists the scale at 20.375 inches, though some retailers quote 21. It's an easy fit for travel, practice, couch playing and small acoustic gigs, and for guitarists who want real bass tone without the bulk.
This one plays great. The rubbery strings feel really fun under the fingers, and the little bass is easy to pick up and enjoy. Cosmetically it's in good shape, with one flaw to note: there's a small chip at the binding toward the bottom of the body. Please see the photos.
- Make: Kala
- Model: U-Bass RMBL-FS Rumbler (Fretted)
- Finish: Satin Natural Mahogany
- Body: Laminate mahogany top, back and sides, black binding
- Neck: Mahogany
- Fingerboard: Rosewood, 16 frets
- Scale Length: 20.375 in per Kala
- Nut: Graph Tech TUSQ
- Strings: Aquila Silver Rumbler polyurethane
- Electronics: Shadow pickup system with built-in tuner
- Condition: Very Good
- Includes: U-Bass logo gig bag
- Weight: 4lbs 1oz
- Known Issues: Small chip in the binding toward the bottom of the body
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.
When you buy from Mill River, you're supporting an independent local business that genuinely cares — about gear, about players, and about doing things right. We're here every step of the way. Reach out anytime.
