Setting nut height on a fretless bass
A while back, I received an email with a question and I thought the answer might be useful to a wider audience. The question was about what height to set the string slots on a fretless bass. There’s some information to be found about string-clearance heights for fretted instruments but not really anything much for fretless.
I’m going to start somewhere far from fretless basses but bear with me. I’ll get back there. 😉
Let’s consider a guitar fitted with a zero fret. If you construct and set this up as I believe you should, you level all the frets—including the zero fret—at the same time. That means the zero fret is in the same plane as all the others. The zero fret is (relatively speaking) the same height as the first fret, and the second, and so on.
Strictly speaking, a regular nut could be treated like a zero fret and the slots lowered to exactly the same height as the rest of the frets. Somewhere along the line, we started leaving them a little higher during a good setup (or a lot higher during a bad one). That’s ok. A few thousandths higher doesn’t cause any problems worth worrying about and the tiny amount of extra headroom is welcome for the open strings.
So then, given a fretted instrument, the zero fret and the regular nut see the strings sit on (or almost on) the fret plane. Any other height and setup is handled at the bridge saddles and with relief.
And so to fretless. If we follow this logic through, we could slot that nut until the strings touched the fretboard. The fingerboard is, after all, the equivalent of the fret-plane in this case. The string height setup will then be done at the bridge and some relief can be dialled into the neck if needed.
That said, most of the time, we leave the nut slots just a fraction higher than this. Like the tiny amount of extra height on a regular fretted-instrument nut, a little extra height on the fretless gives a bit more headroom for the open strings.
So, long story short: As long as your fingerboard is well levelled and setup, you can bring the nut slots waaaaay down to the point where you might be nervous to look at them. 😉 As with most setup parameters, if it’s your bass, keep playing as you lower the slots and see how they feel as you go. If it’s someone else’s try get a feeling as to their preferences and tolerances. Fretless basses—and their players—are different beasts and a little mwah going on is likely a good thing but do make sure. You may want to balance things a little for some players, maybe giving a scoatch more nut height for a smidgen less saddle height—that sort of thing. Fretless allows for a little leeway on playing intonation.
As mentioned in the aside at the start of the last paragraph, this advice assumes the rest of the setup (and especially the neck) is in good shape.
This article written by Gerry Hayes and first published at hazeguitars.com
