My Ibanez is 16mm at the bridge and that's what I like. I started on 4 string and right from the get go I was wishing the bridge spacing was narrower. On standard 4 spacing, I feel like I'm doing more work reaching for the string than actually plucking it. Like I'm driving a dump truck compared to sports car. On a 4 I can deal, but a wide spaced 5 would be very difficult for me to play.
I don't care about nut spacing on a 4, but if given the choice I'd prefer narrower for 5+ strings (Ibanez is 1.75 at nut). Don't want the neck getting too wide.
I don't care about nut spacing on a 4, but if given the choice I'd prefer narrower for 5+ strings (Ibanez is 1.75 at nut). Don't want the neck getting too wide.