Monday, May 18, 2009

Pronounced "Feet-en"

4 comments:

MooPig said...

Flat that fifth to tweek that third... sweetened to taste. Brilliant. Question: Do we all do this naturally after forty years..? I think I have been doing this for a while now, just to please myself.

I seem to remember Ron Roskowske saying something about this phenom of physics and the ear... way back.

Beautiful stuff, Mr Sans

Dave Jacob said...

I don't film 'em, I just embed them.

The part that gets me, though, is that, depending on what chords I form, any string will be the third or the fifth or something else....

Sammy said...

I still have no idea how the system actually works. But I do know a little bit about pre-1690 musical tuning, so that's somethin'.

Dave Jacob said...

There's two bits involved. The first one's easy to get, the next one's tougher.

Part The First: Pythagoras figured out the rule of 18, where, for a given string gauge, a length of string that is 17/18ths the length of a first string, tuned to the same tension, will be one pitch higher than the longer string. Consider a harp. That's how that's set. (The modern number is more like 17.82 or so, but the details can slide unless you're building.)

The first outcome is that, once fretted instruments came about, the first fret is placed 1/17th of the scale length away from the nut, and so on.

Now think about what we, the moderns, do with even hardtail guitars. We bend the strings. Strictly speaking, we bend the strings every time we fret. Take a steel-string guitar and your best tuner. One that intonates perfectly, where the low E is perfectly E at the 12th fret, too. Now, fret the third-fret G. It will be sharp. If you have a death grip, it will be sharper, but chances are, bending the string over the fret stretches it sharp. The solution is to adjust the nut like the bridge is adjusted. Feiten was not the first person to do that. Like the bridge, I'd guess to get dead-on perfect, you'd have to re-compensate the nut when you change string gauges, just like you have to re-intonate the bridge. But if you're looking for better than what you have, I'd guess than any compensation is better than no compensation.

Then again, my #1 is a three-saddle instrument.

Part The Second:Watch a video on steel guitar or dobro and you'll likely hear the instructor tell you to tune the string associated with the third a little flat. If you play DGDGBD (open G) or GBDGBD (bluegrass dobro open G), that's easy. That's because the "real" third is flatter than the third straight lines give you. I talked about this a while ago.Intellectually, I get "more pleasing intervals" as a concept. I've listened to enough poorly-tuned rock that I more kinda go with it than get offended by it. But if he's figured out a way that a guitar can be well-tempered, I am curious.

Read more about it.