I know the basic concept of the strings pulling on the neck creating bow and a truss rod pulling the neck the other way. Now what I'm wondering is does the neck still bow where it meets the body? Like on the top 5 or 6 frets on a regular P or J. I'm wondering this because I'm thinking about how it would affect the way a fret leveling should be done. I like my action fairly low with a very small bow in the neck. If I've leveled all the frets with the neck completely flat and only the "free" part of the neck bows, then the top frets are going to be the first ones to buzz when I bring the bridge height down. I did a fret leveling on my most recent bass, and the action is really good. The top frets do buzz the slightest amount, not enough to bug me but enough to make me wonder if there's some special method of leveling the upper frets.

Not sure what you mean by "top frets"...like #1 to #3 or more like #15-#22? I'm guessing the latter, as you're talking about the neck-body join.

As with guitars, I typically mill a small amount of fall-away into the frets starting at #14. Maybe only 0.010 total difference between #14 and #24.

By top I meant the highest ones. How do you do your falloff?

I first level everything with 600 grit, then work on #14-#24 just spending more time on the higher ones, so that there's a nice consistent fall-away.

You can check it by laying a long straightedge on the frets, registering on the lower (now leveled) frets below #12, and using feeler gauges.

Once you're happy with it, crown & polish as usual.

Say your level up to the 14 fret and have 22 frets. How much fall away would you have at the end of the fret board?
I know a local Luthier that does this too but when I talked with him I forgot to ask this question.

Maybe only 0.010 total difference between #14 and #24.

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