| It's just a matter of adjusting the bridge saddles to get the proper intonation. You haven't told us what type of bass you have, so you'll have to check it out and find the saddle adjustment screws.
In general, the saddles should be aligned something like this:
..........| G
...........| D
............| A
.............| E
But every bass is different, so this is a good starting point. Keep in mind that the harmonic and the open string are dependent solely on the string length; the fingered note depends on both the string length and the fret position. Since the fret position is fixed, tune the open string to a good tuner, then adjust the saddle to get the 12th fret note at correct pitch to match the open string. Of course, it is an iterative process, as the pitch of the open note will change as you adjust the saddle. Once the open note matches the octave, the harmonic should then be corrected as a result. Or, you can match the harmonic to the octave; either way. In general, it's better to loosen the strings to do this to avoid wear on the saddles (and strings), but that makes for lots of tuning/retuning. So, just be prepared for that.
If the 12th fret note is sharp, lengthen the string by moving the saddle away from the headstock. And vice versa for flat notes.
Keep in mind that if you plan to make any other changes; truss rod, action, string change, do the intonation last.
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Last edited by FretlessMainly : 03-10-2011 at 12:18 PM.
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