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Any ideas on the calculating proper compensation for a 4 string acoustic bass?
34" scale
45, 55, 78, 98 guages
Dan Markley PhosBronze Bass
I'm not happy with what I've got now and am making a new bridge. Thanks.
-j.

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“If God dwells inside us like some people say, I sure hope He likes enchiladas, because that's what He's getting”
-jack handy

as far as I recall it's scale length plus the CORE of the string.

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It can vary widely depending on what sort of strings they are. For instance, Thomastik Infeld acoustic bass strings are bronze wound on nylon cores (like the bottom 3 on a classic guitar) and need much less compensation than, say, stainless electric bass strings. On the last bass I built I made a wooden bridge and cut the saddle slot based on the compensation of an electric bass with stainless DR strings on it. I then put the bridge in place and strung it up with just the top and bottom Thomastik strings and a temporary wooden tailpiece. The intonation was miles out and I had to make a new bridge. I suggest you do the same, using the strings you intend to put on the finished instrument. This photo shows how much the first bridge was out. The maple bridge shown was a mock-up with the intonation for stainless strings. The ebony bridge has the intonation for Thomastiks. Click on the photo to see it better.

By the way, I'm just starting on an acoustic bass and I shall certainly do the same thing again when it comes to making and positioning the bridge.

What about stewmacs fret calculator under acoustic it gives compensation so I guess it'd do the same if left set on acoustic for your bass, or what about the intonater?

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Formerly JJH

I learn more from my mistakes than my successes

You can't calculate intonation. It depends of the stiffness of the string (particularly of the core of the string). You could certainly use the intonator to find where to cut the saddle slot.