"Backset" AC saddle?

[Greg Smith]

Hello,

I'm a non-luthier looking for a DIY solution to an intonation problem with an older Godin Multiac nylon-string guitar.

As I understand it, some older models are known to have problems with bridge and/or slot placement.

The guitar's too sharp at the 12th fret on all strings, even with lower-tension strings than the recommended ones. I haven't been able to set the breakpoint on a normal 1/8" saddle far enough back, or the action low enough for my playing style, to compensate.

I know the "right" thing to do would be to take it in to have the slot filled and re-cut. But I'm poor as a churchmouse at the moment.

I have a hare-brained idea of fashioning a saddle with a "backset," as shown in the attached picture. That would allow me to set the breakpoint further back than the back edge of the slot.

Has anyone ever done this? I realize that it will make the break angle more acute, as well as increasing the mass of the saddle and maybe even the pressure against the bridge in front of the slot. But is it a totally mad idea?

Thanks.

Greg

[Greg Smith]

Bob,

Looks like:

322 1/3 mm from nut to crown of 12th fret.
322 mm from crown of 12th fret to crown of saddle.

I'm attaching some not very good pictures taken with my phone, the only digital camera in the house.

Thanks,
Greg

[Len Biglin]

Greg , the way I see it, sharp notes fretted at 12th or higher are mostly due to bridge position , sharp notes fretted in the first few frets are mostly due to nut position and height,chase these perameters and you will get closer , although the nut and saddle do effect the other end to a noticable degree , as you get close to perfect at both ends the culprit will show up - or dissapear WITH the problem .Hope that makes sense .Len . . .and PS why do CG's tend to have the nut so high?

[Greg Smith]

Len,

Thanks. Don't know why the nut is so high on CGs. I just know that the action on my Contreras is on the high side, as in 5/32" at the 12th fret on the bass E. I've got hard-tension strings on it, but it feels comfortable, no problem playing barre chords high or low, and I can play it as hard as I want without buzzing. The differences between the harmonics and fretted notes at the 12th fret, although I've never measured them with a tuner, seem almost nil to my ears.

Greg

[danove]

Also, higher tension strings are less stretched when fretted.

[Greg Smith]

Finally got around to trying my idea:

http://www.stanford.edu/~gmsmith/saddle/compensated%20saddle%20008.JPG

Intonation's much improved, and now that the saddle has been broken up, there's much more room for compensation. Unplugged tone, say what you will about Godin Multiacs, doesn't seem to have suffered.

I finished roughing out the saddle pieces only today, and am waiting for the strings to settle before plugging in and finding out how things sound through the under-saddle pickup. I guess that'll be the real test.

Greg

[Antonio Cotichini]

It's horrible ! Seems a guitar with a denture ! But my doubt is: how can the string press the saddle-piece AND the piezo pick-up correctly? The pressure isn't perpendicular, the nylon strings aren't the best for tension and pressure... I can't imagine the tone of the guitar when plugged!

[Greg Smith]

Thanks. We'll find out how it sounds plugged soon. Under-saddle pickups aren't very nice-sounding to begin with, and they need a lot of post-processing no matter what. I did a lot of thinking about this, and I shaped the pieces so they wouldn't simply torque around the back edge of the saddle slot, in which case there would be no downward pressure at all. It's true that what downward pressure there is will be concentrated on the front part of the pickup ribbon.

[Tim Mace]

I'd be tempted to widen the slot,stick in fatter bone and compensate.

[Antonio Cotichini]

Yes, it's the simplest (if not only) way I'd go for. It's not an expensive work. You should do it by yourself with a Dremel, the right size milling cutter, a template and... a lot of attention.

[Greg Smith]

I thought about widening the slot and putting in a fatter saddle But even that approach would produce a less-than-optimal pressure on the transducer ribbon unless it were moved over to be in the center of the slot, lengthwise. And that would take me into really virgin territory, as a DIYer.

I know I could just grit my teeth and take it to a pro repairperson. The nearest one is just down the street from me, but I'm not happy with the saddle-work he did on one of my steel-strings.

I'm lucky enough to live just a few miles away from Gryphon, where Frank Ford works. He's not cheap, but he does magnificent work. I would be embarrassed to take a Godin to him (Gryphon sells Rick Turner Renaissance guitars there, and they're the real thing.) Right now I'm saving my pennies to have him reshape the headstock on this one-of-a-kind beauty:

http://picasaweb.google.com/dansereal/11CourseLutar#

Greg

[Tim Mace]

Send it to Godin . They should be responsible enough to correct an ill manufactured saddle .

[Antonio Cotichini]

Greg, did you consider to change the under-saddle transducer with a different kind of piezo (as the KK Pure Western)? This way allows you to enlarge the saddle to have room for good intonation.