set up question: action vs. tone

I've got a question for all you experts out here on MC. I recently re-fretted my Kentucky-850 with evo gold fret wire, and am very happy with the resulting flatness of the board and look of the frets. As well as scooping the Florida, cutting a new bone nut and sanding the bridge to sit better with the sound board!

But, since I've done so, I've adjusted the bridge to a higher position and found a tone that I cant go without now. its like the strings (using exp 74cm) are at the right tension, and just sounds right! the problem with that is I'm sacrificing action for this better tone. Rob Meldrums ebook on set up helped my journey a lot, and when I was setting up the action I tried the strings at his suggested height: .050 at twelfth fret, but my lowest that works on my mandolin is .110.

So, my question is: is this too high? for me, I'd definitely want it lower, but I'm no shredder. if I used heavier gauge strings would I be able to lower the action? is my fretboard at the wrong angle to my strings? thank you for input!

-Patrick Grant

I find that if you raise or lower the bridge you must adjust intonation. When you raised your bridge you made it intonate better. I would guess if you lowered the bridge to where you like it then intonate that you would find your tone at the lower string height. Mandolins are very finicky.

I have always thought that, as each mandolin has a particular string it likes, it has an ideal height of it's strings. Down pressure on top, how heavy handed player is, or just the finickiness of the mandolin or whatever causes it I always experiment with height on a new mandolin to find what it likes best.

I have found, like you, that there is a difference in tone and volume when you raise the action above the minimum height required to avoid buzzing, especially on the E string. Action set at the minimum height leaves the unwound strings sounding more constrained, while raising it allows you to pick with more force, resulting in a fuller and louder sound- important if you're playing in a bluegrass ensemble. I'm not sure of the physics involved here because it's not like the strings are slapping on the frets. At any rate, The best compromise I've found is to get the nut dialed in as close as possible, like around 0.007" clearance at the first fret, and then raise the bridge to where the tone sounds best. Hopefully some of our more experienced builders will weigh in here. BTW, +1 on EVO gold, I've had it on a couple of mandolins for several years now with almost no sign of wear.

IMO .110" is verging on the unplayable. Even .080" (which will seem OK at first) will quickly leave your fingers sore if you're not careful. You should ideally be looking for .060 on the G and .050 on the e. A touch higher is OK, but your fingers will thank you for a decent action.

Greater break angle over the bridge increases pressure on the top right? So if you double your action will that increase the pressure on the top respectively? Maybe a good action and a bit higher tension string would accomplish the same thing?

Quote:

---

Originally Posted by John Bertotti

Greater break angle over the bridge increases pressure on the top right? So if you double your action will that increase the pressure on the top respectively? Maybe a good action and a bit higher tension string would accomplish the same thing?

---

Increase in bridge height will increase pressure on top but not enough to really change things audibly. The increased action will make player press harder on frets and thus help produce cleaner tone (especially if previous action was a tad too low) so many folks think increasing the angle or pressure helps tone.
Mr. Krishot (Czech luthier) recently started building mandolins with longer scale (approx 1/2") and neck joined with 14th fret at crosspiece. They feel stiffer to fingers even with ultra low action that can be set on higher tension strings but didn't sound way different from his "normal mandolin". Most folks wouldn't notice.
One (award winning) violin maker did experiment where he raised tailpiece up to almost level of bridge and reduced break angle almost to zero and change in tone was rather unsignificant. Of course the increased leverage on the neck block changed other aspects as well but the main point, IMO, is that the changes often need to be really much bigger than folks expect to bereally audible.
On many instruments that folks brought to me which didn't work properly I could find plausible reasons quickly looking at construction showing big differences from good normal mandolin (like tone bars of double size or poorly carved arch, failing neck joint etc.)

I saw an interview with Herschel Sizemore talking about getting a good tone, and one thing he mentioned is adjusting the bridge to its ideal height. that stuck with me, and thinking of downward pressure from break angle makes a little more sense to me with this in mind. one reason Im still thinking this its the case is the open strings even sound so much stronger and more volume. not just when Im fretting a string or any intonation being off.
on the flip side, I've heard of people with this model mandolin finding the tone bars to be extra thick and shaving them down "opened up" the sound a lot.

Quote:

---

Originally Posted by patrgrant

I saw an interview with Herschel Sizemore talking about getting a good tone, and one thing he mentioned is adjusting the bridge to its ideal height.
on the flip side, I've heard of people with this model mandolin finding the tone bars to be extra thick and shaving them down "opened up" the sound a lot.

---

That "ideal height" may mean so many different things... using vague vocabulary asks ffor many interpretations. I've played for many years one mandolin and found that for me it plays best with x action (and bridge set up for best intonation) When I sold it to a friend he needed different action for his playing... pure listener will hardly notice any difference in tone but the player will feel difference with his left hand.

Wouldn't intonation be farther out between open and fretted strings with a higher bridge? I would think this would be an additional problem aside from the physical difficulty.

Quote:

---

Originally Posted by Greg P. Stone

Wouldn't intonation be farther out between open and fretted strings with a higher bridge? I would think this would be an additional problem aside from the physical difficulty.

---

Of course you need to adjust intonation with each change of bridge height.

As a full time guitar tech servicing mainstream customers for quite a while, I often get clients who want the lowest string action with clear notes. Unfortunately, its not always possible to meet the expectations of a client when they've experienced playing an instrument with uncommon mojo. Great instruments happen.

Certainly, there are makers who build hyper-quality instruments and there is a value to well made things built with integrity. But there is a lack of understanding that every instrument is unique and the fact that although one instrument might be gods gift to mankind, another that is built exactly in the same fashion simply will not be the same.

Two instruments built on the same day with perfect geometry and fretwork are likely to play at their best and yield their best tone with different string height and trussrod settings. It is just the nature of wooden stringed instruments. There is a lot more going on than just geometry and this is something I've been trying to study forever without ever really being able to establish any rules. There are general guidelines that can steer you toward the optimal setup but numbers and specs are just generalities. Some instruments simply lend themselves to great tone with low action while others can be quite uncooperative. With frets leveled to the greatest tedious precision and relief adjusted to the optimal setting, the geometry might be perfect but other things must cooperate also.

The vibrating energy of the strings travels all through the instrument and through the different and uneven densities of the structure this energy travels at different speeds, reflects, interacts, combines and generally become a chaotic mess as one frequency interacts with another creating new wave-forms. This chaotic mess of energy reappears almost instantaneously at both ends of each string and if it is not a harmonic that is in phase with the string, it will disrupt the natural vibration that the string wants to maintain. The less of this interference of energy present at either end of the string, the longer the string will sustain a clear and pure tone. The problem is that not only do we have the energy of an individual string initiating this chaos, there are seven other strings injecting additional energies at different frequencies. Its not only the strings and their natural pitch at any given fret position that we hear. Its the chaos of all of the reflected energy that gives the instrument its unique character. Sometimes this chaos is so prominent that it can become destructive to the original frequency and cause the string to become wildly unstable. Although the initial energy is a clean tone, the way the energy travels through the instrument and is reapplied to the ends of the string (at the bridge, the nut, or the fret) is most often slightly disruptive. Sometimes, instead of the string ringing true it degrades quickly and become corrupted with wild deviations that often manifest as what is assumed to be fretbuzz. Both the corrupted vibration and the fretbuzz are unpleasant but its not always the geometry of the neck/frets/string-height that is causing it.

Its not that the phenomenon of reflected energy is bad. I've played a solidbody guitar built entirely from aluminum with a high-mass bridge and I've never heard a more terrible and sterile tone. The issue is totally responsible for the character and flavor of the tone. It can make and instrument sound sweet and rich with beautiful rewarding overtones. Every instrument is different and specs and measurements are only guidelines. Sometimes you get lucky and sometimes you get less lucky.