general intonation question

[danglybanger]

what facilitates the need for intonation? Why do some strings need to have a slightly longer or shorter scale length than another? Sorry, but this never made sense to me... can someone please explain?

Also, why is it that the string saddles always seem to slope up from the right (on RH guitars anyway) and dip on the unwrapped strings?
thanks,
dan

 

[rspst14]

Re: general intonation question

Also, why is it that the string saddles always seem to slope up from the right (on RH guitars anyway) and dip on the unwrapped strings?
thanks,
dan

Are you referring to the different heights of the saddles? If so, it's because the saddles should be set to match the neck radius.

As for intonation, I'm not 100% sure of the exact logic behind it, so I'll let someone else answer that.

Ryan

 

[danglybanger]

Re: general intonation question

no, I'm not talking about string saddle height... i'm talking about the way the intonation of each individual string is set. from left to right, (sorry, I think I worded that part wrong on my first post) the saddles are adjusted closer to the nut progressively from the E to d strings, at the g string the saddle goes farther from the nut again, and closer to the nut again on the b and e strings. I want to know, basically why intonation is necessary, and all the strings can't have the exact same scale length.
dan

 

[Grandor]

Re: general intonation question

Because its impossible to have a perfectly intonated instrument with frets (buzz feiten helps). Our western chromatic scale cannot be put down to a fretted instrument and be perfectly intonated. About all the strings not being the same scale length - I believe that has something to do with the guages of the strings...


I think.

 

[rinse_master]

Re: general intonation question

Yeah, sounds about right, I mean a piano has loads of strings, all different lengths...

 

[rspst14]

Re: general intonation question

I'm going to say it has to do with the relationship between the gauge of the string and the tension on it. An 18 gauge wound G string will intonate differently than a 17 gauge plain steel G string, just like a 46 gauge E string will intonate differently than a 42 gauge E string. Everyone knows that fretted instruments can't play 100% in tune, although Buzz Feiten and Earvana have tuning systems that help correct this to some extent.

Ryan

 

[Kent S.]

Re: general intonation question

I believe it has to do with the deflection angle from the height of the string being fretted ... various gauges and scale lengths exert different tensions upon the strings when tuned to pitch. Combined with the fact that different strings will be stretched more or less when fretted, and the resulting tension change upon the string in accord with it's effective scale length being changed ... well, it will *bend* the string sharp, so the saddles are positioned to give lee way in either the sharp or flat direction to accomdate this change.
If all of your strings were tuned to the same pitch, were the same gauge, and were the same distance (height) from the fingerboard, then the saddles could all be in the same place.
Or, something to that extent ... It's just the physics of the materials involved ... Like I said, something along those lines.