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Could someone explain to me the tilt of the saddle and the B string compensation on the saddle?

Mike

The amount of compensation required varies depends on many factors including the material of the string, how far the string is being stretched, the thickness of the string, whether the string is wound, etc.

A B string, which is typically the first unwound string on a SS requires more compensation than would a string of that size if it were round.

Some builders tilt back the saddle so that as the height of the saddle is lowered or raised the amount of compensation changes with it. Some also believe that helps the tone of a UST. Personally I tilt but I think the majority of builders don't.

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David White, Toronto

"All my favourite singers can't sing."

The closer a given string is to its breaking point, the better it will intonate. If the tension of the strings is pretty much equal, the string closest to breaking is the third (g) in a std acoustic set .. why - because it has the smallest core - the wraps only add mass to drop the pitch. So thus the 3rd and 1st strings need less compensation than the 2nd, thus the 2nd string setback. The wound strings will all slowly drop further back on the saddle as the core gets larger. Another factor is the string's stiffness, because this affects the true speaking length of the string (ie - it takes a minute distance from the saddle before the string actually starts vibrating) - so we add more string length to compensate ...

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

I've always wondered why some are tilted, split or a continuous piece. Saddles are designed for a specific string type then? Seems a lot to ask of a new guitar owner that you need to use only a specific brand of strings. Can't say i've ever heard of a salesman say "Yessir, this guitar comes with 5 saddles depending on the strings you want to use". Of course the salesmen at walmart normally aren't aware of the difference between an electric and an acoustic. I need to go upscale maybe?

I'm not doubting that it makes a difference mind you - if any of this makes sense to me, i can see that altering the length of a string changes the way it plays, but i'm curious how you determine compensation based on the strings to be used? Phosphorus adds 1/32, silk and steel subtract, heavy add...?

Oh, it makes a difference, I can assure you! I am just trying to understand why. And, are there any calculations, specific saddle angles etc. Surely someone has put together a spreadsheet? Per wire gauge? You see, think I am getting into the very most secretive part of guitar building here. Anyone can copy a body... but the bridge, saddle, nut, well thats where the rubber hits the road and make all the difference. I'm just hoping someone will share this.

Mike

I have a program somewhere i got off the MIMF and it gives comp calculations .. but you need a whole lot of info to do it .. core size, stiffness factors ....

Something that will also throw it all off is the action setting on the guitar - higher action, more comp .... the only way to really check is to put the strings on and see how it tunes ... then adjust the break point as req'd.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Like Tony said It all boils down in the end to getting Open, 12th fretted and 12 harmonic to play the same pitch and having the stings play in good temerment with each other up and down the fretboard

Most steel string acoustic players use pretty similar strings: the lower four are wound and the B and E are plain. A plain G is slack enough to require much more compensation, and it bends so easily (for the same reason) that it's hard to play in tune on an acoustic. Generally speaking the 'normal' saddle angle works pretty well for most players and most strings if it was done right to begin with.

Now, if your customer plays jazz, and spends a lot of time up over the body, you will almost certainly have to intonate each string individually. Find out what strings he/she likes, set it up with the proper action height and neck releif, and then get to work with the tuner. Good luck.

You'll need it. There are so many things that can throw the intonation of an acoustic guitar out that I sometimes wonder that they ever play close to in tune. Maybe it's a good thing that we use the compromise of equal temperament, in which all of the intervals except the octave are a little out, otherwise we'd never be happy.

Below is a link to David Hurd’s web site that shows a string compensation jig. You can use it to check compensation using different scale lengths. As long as you used the same strings and frets as the guitar then the results should be spot on.

Philip

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aka konacat

If you think my playing is bad you should hear me sing!
Practice breeds confidence and confidence breeds competence. Unfortunately, I'm stuck in practice.

Below what?

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

I guess it helps if I post the link. Hmm, I don't see an edit button so here is a second post.

http://www.ukuleles.com/Technology/compensate.html

Philip

_________________
aka konacat

If you think my playing is bad you should hear me sing!
Practice breeds confidence and confidence breeds competence. Unfortunately, I'm stuck in practice.

Thanks!