The guitars most associated with Django Reinhardt and Gypsy jazz are those made by the Selmer Company, a French instrument maker. Selmer didn’t make or sell guitars until Mario Maccaferri came to work for the company. Maccaferri designed the “grande bouche” (big mouth) Selmer. The guitar has a large “D” shaped sound hole (see image – top left). This guitar is sometimes called the Selmer-Maccaferri guitar.
The Selmer-Maccaferri guitar came out in 1932. The guitar was one of the first with a truss rod, something invented by Gibson in 1921. It was the first guitar with a cutaway. Gibson didn’t have a cutaway guitar until an L5 model in 1939. Epiphone, D’Angelica and Stromberg didn’t have cutaway models until 1949 and Gretsch until 1951. But not every innovation was worth keeping. The design had an internal resonator which was eventually eliminated. Most vintage Selmer guitars have had the resonator removed.
Maccaferri was only with Selmer for about eighteen months. The guitar which Django made famous was produced by Selmer after Maccaferri was gone, in 1936. This guitar was called the Modèle Jazz”, or “Petite Bouche” (small mouth) or just the “Oval Hole”. They are sometimes referred to as Selmers (as opposed to Selmer-Maccaferris). They had a longer scale length (670 mm 1 ) and the small oval sound hole (image – right). Longer scale lengths result in the strings having more tension (for same gauge strings) which produces a louder guitar. The Petite Bouche style is thus favored as the lead instrument in Gypsy Jazz ensembles where often two or more guitarists play rhythm.