The 5-String Double Bass

[David Powell]

I know this verges on insanity, but a French luthier has made one with 7, and the player does use a bow. His primary work is improvisational jazz. I have one of his older recordings using a 5-string, but this is the instrument he's playing now:

and here is a photo of the outline (different instrument, same maker, Antoine Leducq) compared to a gamba:

It reminds me of Savart a bit. At the risk of this becoming the quest for "one that goes to eleven" I'll stop with the lucky number. It's a bit over the top, but you have to wonder if one plays all double stops on these things with so many strings.