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Intonation Calculator?


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I'm curious...does anyone know of an intonation calculator or formula that will provide the exact locations for intonating at a given scale and string guage?

For example, using a bridge like this shouldn't it be possible not only to position the bridge exactly, but also to reshape it in such a way that each string is exactly intonated?

I remember Mushy the Shroom's guitar --believe he had a single strip for the bridge saddle on there, and that's it.

There's the compensated wraparound bridge -- are those ridges exact, or are they approximations?

I just have it in my head that it must be possible to have a solid non-moveable bridge-- you have to figure that all the little parts on most bridges are doing something to the sound. My hypothesis is that the fewer the number of parts, the better the transfer of vibrations.

So if you've calculated exactly where each string needs to break from the saddle, then in theory, all you'd need do is take a bar of aluminum, for example, notch/shape it accordingly, and fasten it down tightly to the surface of the body.

Or if you want to retain flexibility, make a bridge similar to an acoustic, with a replaceable bridge--just two parts in that case.

Seems to me that this is not practical in a manufacturing environment, but for the hobbyist tinkerer, it should be possible.

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Nope, it's about overcoming the stiffness inherent in the string, and has nothing to do with trig in the sense you're proposing it. I believe there's a compensation calculator linked from the MIMF link pages, but I'm not sure.

All these preintonated doodads are general approximations that work well with most sets of strings. Best to just intonate each string individually with a removable temporary saddle if you want to make a 'fixed' saddle setup. A la StewMac intonator (check their tools), if you will. Thing is, don't change string tension, string brand, guage, and whatever you do, do not change tunings and expect it to stay put and play neatly in tune. in practice, a pretty broad range of string guages and tunings will work OK before intonation goes appreciably off, and how off depends on the player (compensate, how hard do you grip the strings) and his sensitivity to 'out of tunedness'.

Honestly, I don't worry overmuch about the 'moving parts' in electric guitar bridges, particularly not those that are held firmly in place by string tension and/or bolted/screwed in place (locking saddles on Schaller's 3D bridge, tonepros, wilkinson's adjustable wraparound, wilkinson's regular modern terms).

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Thing is, don't change string tension, string brand, guage, and whatever you do, do not change tunings and expect it to stay put and play neatly in tune. in practice, a pretty broad range of string guages and tunings will work OK before intonation goes appreciably off, and how off depends on the player (compensate, how hard do you grip the strings) and his sensitivity to 'out of tunedness'.

The height of the action will also affect the intonation...

Brian.

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Unless you've got a compensated saddle, most acoustics are just "in the ballpark". To adjust the intonation you'd have to fill the saddle slot and re-route it in the correct location.

Is Mickguard just curious, or has he abandoned the "close enough for rock-n-roll" camp? :D

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Well, acoustic guitars have fixed saddles that aren't intonatable -- so how are they intonated?

Straight saddles are a "good average". Split saddles are a little closer. Some models use a modified saddle that is cut for different string breaks. All can be refined a bit more with shaping.

This is something you can test and work with first hand. Look at your guitars. See what it took to get them intonated correctly. Take notes on scale length, string gauge, tunings, and actual lengths. You could probably get one model guitar(scale length and what have ya) using a certain gauge string and tuning pretty darn close. It doesn't make a lot of sense though to limit yourself unless you have a compelling reason (as is the case with acoustics where extra weight of hardware would be unacceptable).

Peace,Rich

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Part curiosity, parly because I play in a band with a keyboard player with perfect pitch :D

I play with two of those, a keyboardist and a guitarist.

But we get along because, even though I don't have "perfect" pitch, I'm at least as **** as they are about tuning. :D

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Part curiosity, parly because I play in a band with a keyboard player with perfect pitch :D

I play with two of those, a keyboardist and a guitarist.

But we get along because, even though I don't have "perfect" pitch, I'm at least as **** as they are about tuning. :D

I found a different solution...the keyboard guy and I are forming a new group, but he's switching to drums for that one. First practice is this week, it's going to be a blast. We're hoping to start doing shows (as an opener) in late fall/early winter.

Anyway, I'm just wondering what that might sound like, to have a single solid piece of aluminum as a bridge. Possibly it might not sound any different from an aluminum wraparound (or any other bridge), but it'd be interesting to try.

But yes, I suppose I can just measure my other guitars to get an idea of the distance for each string.

Still, you'd figure some math whiz would have already worked this out--and created an applet for it.

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Part curiosity, parly because I play in a band with a keyboard player with perfect pitch :D

I play with two of those, a keyboardist and a guitarist.

But we get along because, even though I don't have "perfect" pitch, I'm at least as **** as they are about tuning. :D

I found a different solution...the keyboard guy and I are forming a new group, but he's switching to drums for that one. First practice is this week, it's going to be a blast. We're hoping to start doing shows (as an opener) in late fall/early winter.

Anyway, I'm just wondering what that might sound like, to have a single solid piece of aluminum as a bridge. Possibly it might not sound any different from an aluminum wraparound (or any other bridge), but it'd be interesting to try.

But yes, I suppose I can just measure my other guitars to get an idea of the distance for each string.

Still, you'd figure some math whiz would have already worked this out--and created an applet for it.

Maybe you would find something of interest here. Intonation comp.

Peace,Rich

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Maybe you would find something of interest here. Intonation comp.

That is indeed interesting. Although that's more of an after the fact adjustment.

I guess what I need to know is the optimal length for each string --I imagine that's common knowledge and I just don't know where to look?

For example, on a 624 mm scale, which is what I'm working with, the High E saddle should be at 624 mm, right?

On my guitars with compensated wraparounds, the B string saddle is positioned at about 630. And the Low E is positioned at about 634.

I don't have a long enough ruler right here, so these measurements aren't entirely accurate--still, it should be enough for someone with a bit of math in them to work out a formula that way, no? Or maybe just adapt the compensation formula.

String guage is .10 -.46.

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There is no optimal string length, because it depends on brand, guage, tuning and scale length. Shorter scales need (percentually) more compensation than longer scales, as a rule. The best way to do this: set up a guitar you have with the scale length you want to use, the strings you want to use, intonate, measure, and use those measurements. Or intonate on the guitar itself, using something like StewMac's saddlematic for each instrument/string set/etc.

As a rule, you usually even need a slight amount of compensation on the high E (up to about 1mm), up to about 3mm for the low E. I'll keep looking for that mathematical compensation model, but end of the day, it's just as simple to find ideal compensation experimentally.

Besides, you gonna compensate the nut as well? Because there's stuff to be gained at that end as well (look at the MIMF website, Stephen Delft's article on nut compensation).

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