1933 Kalamazoo (Gibson-made) KM-11 Flaback Mandolin




I've worked on a lot of KM-11s, recently. Click here, here, and here for a few others to gape at. This one looks pretty original at a glance, though when you check it more closely you can see that the whole thing has had a shot of overspray (that's greyed on the back/sides) and the tuners and bridge are swapped-out.

These KM-11s were made in the Gibson factory... by Gibson. Its factory order number suggests a 1933 build and the headstock style and "Made in the USA" stamp on the back of it confirms that idea.

It came here with the frets on the extension missing, a too-short bridge, and bad ebony nut. I gave it a board plane and a refret, cut a new (proper-height) rosewood bridge, fit a new bone nut, and set it up. Of course, refretting anything old like this (and with original, worn, teensy-tiny frets) gives you a ton of extra juice from your instrument -- more sustain and fullness to each note, a faster/easier feel, and an accurate board. It's an upgrade I don't often get to do on middle-road instruments like this one.

Coming-out the other side of work, this thing plays on-the-dot and has a loud, punchy, aggressive sound. It can easily hang tough with traditional "bluegrass" mandolins and has good chop and bark, too, though it's not quite as dry and poppy in flavor.

Normal Gibson approaches apply -- it has a 13 7/8" scale length and a body shape directly borrowed from Gibson A instruments. The top and back are flat, however, and the bracing is a curious x/ladder hybrid layout. The top is spruce and the back, sides, and neck are mahogany. The board and bridge are rosewood.

Setup notes: strings are 36w-10, the neck is straight, and action is a hair under 1/16" at the 12th fret.

Condition notes: unoriginal tuners (nice Grovers), unoriginal bridge (but comp'd and cut in the same fashion as the original), refretted, and overpsray throughout. Various light scratching throughout, too.











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