Intonation

[PocketGroove82]

Hey TB crew,
I've been doing setups for years and years and I've never had a problem getting proper intonation set by adjusting the screw at the base of the bridge, thus sliding the saddles forward or back.
As far as I've understood, the length from the nut to the 12th fret is exactly the same as the length from the 12th fret to the bridge saddle which creates the 12th fret and 24th fret octaves.

Since this is true, wouldn't we expect to see more properly intonated bases with bridge saddles lined up all in a row? But most of the time we see basses with the lowest string saddles far back while the higher strings are closer to the pickups.

I'm really interested in learning what causes this phenomena.

Thanks for any responces.

matt

[tbone0813]

I believe one factor is the gauge of the string, but I could be wrong.

[Khronic]

Intonation is a function of string heighth. The higher your action, the further you have to bend the string to contact the fret or fingerboard. The further you stretch the string, the sharper the note will become. (i.e. higher action=more stretch). Larger gauge strings require higher action to avoid fret buzz, hence the "E" string saddle needs to be further from the twelfth fret than the "A" string saddle and so on.

The proper tuning of a stringed musical instrument is a series of compromises and you'll find exceptions to any and all rules.

[PocketGroove82]

Many thanks for the info, Naimishbridge.
I've always wondered what the physics were.