Intonation Issue/Observation

[jshane]

I changed strings last week-- put on a set of DR-11's. Now these are one of 2 or 3 of my go-to strings. They work well on my Pava- perhaps a bit bright for the first day or two, but generally a great match.

Well, I was almost immediately unhappy. I was having a terrible time with awful sounding (to me, anyway) chords. Songs I have played for years were sounding stilted and just "off". No matter how much tuning etc I went thru, nothing seemed to help.

This morning, on a bit of a whim, I noodled around way up the neck. Now, I really dont play up near the 12th fret much- except for the occasional solo excursion --but my noodling sounded AWFUL. So, I checked the intonation at the 12th fret and it was uniformly sharp by a few cents across all the strings.

A quick bridge adjustment fixed it, and BINGO, everything in the first 8 frets or so was back and sounding great (well, as great as it usually sounds, which is open to interpretation ).

I am astounded at the influence near the nut of what just a very minor error in intonation at the 12th fret had. And not just on the note-precisions, but I feel that the whole tone of the mandolin box itself seems to ring cleaner. Is it possible that an imprecision in intonation influences overtones enough to cause this???

Don't know if anyone else has had this experience, but I am going to be much more diligent about checking my bridge-position, that's for sure.

[UsuallyPickin]

I check my bridge location setting by matching the twelfth fret harmonic , noted tone and the open string for pitch with my most accurate tuner. Over a few months or instantly during a string change when the downward pressure is reduced on the bridge a slight bump will move the bridge enough to cause intonation issues. I set my mandolin bridges using the outer E and G strings tuned to pitch with the inside six strings loose. Play on .... R/

[Ivan Kelsall]

jshane - You did exactly the right thing - check it out !. If 'all of a sudden' something changes,it's usually something 'physical' that can be changed back (hopefully). By this i mean there's no 'structural change' to the mandolin itself.
I've found that temp. can affect the tone of my mandolins.They go sharp when cold & go flat when warm. Humidity is something that you folk in the US have to contend with as well. It's not so much of a problem over here in the UK - but..... !,
Ivan

[John Kelly]

Bearing in mind the short scale-length of mandolins, any misplacing of the bridge will have a much bigger effect on intonation than you'd find on a longer=scaled instrument - guitar, bouzouki, etc.

Re humidity, Ivan is right about here in the UK - he's in Lancashire and I am in Scotland (even further up the map). It is nearly always wet here, even on a dry day, so humidity not such a problem!

[Tobin]

I am astounded at the influence near the nut of what just a very minor error in intonation at the 12th fret had. And not just on the note-precisions, but I feel that the whole tone of the mandolin box itself seems to ring cleaner. Is it possible that an imprecision in intonation influences overtones enough to cause this???

Yup. Having the intonation set as closely as possible to "true" (as much as can be attained on a fretted instrument in 12TET) will make a big difference in how it sounds. The darn thing just seems to come alive and thrum in your hands. It will resonate a lot more fully. Even a tiny fraction of an inch can make a huge difference on a short-scale instrument.

Violin/fiddle players use this a lot. Since they don't have frets and can't set intonation like a mandolin, all intonation issues come from where the player puts his or her fingers on the fingerboard, and even the slightest finger movement or tightening of grip can affect it. When you get it "just right", there is a harmonic response from the instrument as it excites the overtones on other strings and the body itself. Generally speaking, there are a few places (notes) where it is very pronounced, and they train their ears to listen for that response to ensure they're playing in tune. It's very real, and it takes very precise placement to achieve.

While mandolin players can't adjust intonation on the fly as we are playing, we can indeed train our ears to hear a similar response when we are adjusting our bridge positions. You just experienced it, and next time you tweak your intonation, you'll know what to listen for. There's much more to setting intonation than simply checking tuning at the 12th fret. If you don't play up there very often, you might want to set your intonation to be optimized at, say, the 5th or 7th fret. That may yield an even more lively response from your instrument for the type of playing you are doing.

[Tom Wright]

Given your strings were playing sharp, you moved the bridge back toward the tailpiece. This not only improves the 12th fret intonation, it would lower the action at the low frets slightly, which would allow those low frets to play less sharp. So even though the main effect of bridge placement is in higher frets, moving the bridge can change the action overall, and affect the low frets as well.

Similarly, moving the bridge toward the fingerboard will raise the action a bit, which will make the instrument play more sharp in both low frets and high, as it changes both effective scale and action height, and both affect pitch.