So I hear a lot about compound radius fingerboards. Here's what I say. To quote Chuck D (Public Enemy), "Don't believe the hype, it's a sequel, as an equal, can I get this through to you?" haha. Public Enemy not withstanding, to understand this, understand what it is, and what the radius of your fingerboard really is.
To understand the fingerboard radius, take the one I use for example. 12" radius. Draw a circle with a 12" radius (distance from the center to the outside edge) (that's a 24" diameter - distance all the way across). Now, look at your fingerboard. Usually a little less than 1 3/4" across at the nut, and about 2" at the 12th fret. Cut that distance out of the circle and you have the radius of your fingerboard.
A radiused board is uniformly curved its full length, as if it were the top of a cylinder. Typically, guitar strings are not parallel: they're closer together at the nut, and they spread wider apart at the bridge. For this reason, people feel that if you use a straight radius down the board, the strings would rise too far off the fretboard at some points. So the compound radius was born. For example, you may see one radius (say 10") at one endof the board, and another (say 16") at the other end. This causes more of a taper (or conical shape) to the fingerboard, which is said to track the string taper more evenly for more comfortable playing. Sounds awesome, huh?
Yeah well, what does it really mean to you? I've made a drawing to scale and shown you 10", 12" and 16" radius overlayed, then two sections of the neck (nut/red, 12th fret/blue). Look at the edge of the sections of the fret board and look for any perceptible difference. Here's the math. When you're dealing with a 2" section of a 24" circle v. a 2" section of a 20" or 32" circle, your talking about a variation in radius of the fretboard that is so small, it can't be measured unless you have a very particular ruler that can give you, at minimum, hundredths of an inch. Most rulers will give you 1/16, or maybe 1/32. This is 1/100. Your talking about a distance less than the difference between a 9 and 10 gauge string. While we can feel the difference between them, it's not the string size we're really feeling, it's more the tension of the string.
So here's my thought. While it's fine in theory, the reality of you feeling it, or particularly feeling any effect of it, is slim at best and none in reality. What it is, is complicated to make and expensive, for little benefit at best. And we're talking about wood here, not precision machinery. And we're talking about fractions so small, they're nearly imperceptible.
BUT............ what does make a difference is something most people ignore or forget about. When you feel a brand new compound radius guitar, then your own, you may want to throw rocks at your guitar. But it's not really the radius. When is the last time you had the height of the bridge saddles checked?????? Oh yes, more likely your issue. The height of the bridge saddles should match the radius of your neck. Have that adjusted and you're guitar will feel a ton better! Rather than spending a pile your hard earned money on a brand new shiny compound radius neck, try a few bucks on a professional setup! And maybe check out a little old school Public Enemy.