I'd like to change pickup on my musicmaster bass to Curtis Novak BS-DS. I checked their website and it has 3 options 15.6mm – Vintage Hagstrom Bisonic, Starfire, and Gibson 17.4mm – Fender Pbass, and JazzBass neck 19.0mm – JazzBass bridge So, which one is right one for musicmaster bass?
Email him and he'll send you the right one - that's what I did - with new strings and cutting the tone-suck capacitor, it improved my Musicmaster's tone. Without doing those extra things, I really couldn't tell a difference between the Novak and the stock pup. And the Novak is not a humbucker either.
Unless I'm mistaken the string spacing on Musicmaster is 17mm. That was the spacing on the Nordstrand I had in a Musicmaster body for some time. It worked well.
Yes I think I recall Musicmaster bridge spacing to be around 16mm, so 15.6 should be good at the pickup.
The spacing on my '77 Musicmaster is roughly 17.83mm (basically 18mm) at the bridge, 16.33mm over the pickup. Some pickup makers like Aero might actually ask for a spacing spec in 10ths of a mm. A Bi-Sonic in there would be pretty bada$$ but I've also been pretty impressed with the Aero Musicmaster bass pickup (4 poles for bass in the Strat guitar shape) and a red Lace Sensor.