Hi all
I bought a Guild D140CE around 4 months ago. I absolutely loved the booming sound it gives out.
The only problem was the action was quite high so I lowered it a little by sanding the bottom of the nut.
I assume that was a typo because you say:
"I might get a new saddle and put it back to how it was"
and "Would lowering the action have that effect?"
The answer is that in fact yes the saddle
does directly impact volume but it is somewhat surprising that it sounded that apparent to you.
I'm guessing you might have lowered it a "lot", like an 1/8" or more.
And yes, a guitar sounds very different from right in front than from the player's position so an audience may well
not notice.
What others said about ensuring saddle's bottom is perfectly flat for full contact with bottom of bridge slot is true, but assuming you did do that properly, here's the physics of how strings make a top vibrate:
The angle of the strings over the saddle is called the "break angle", that angle behind the saddle created by the location of the pin holes and the height of the saddle.
The
taller the saddle, the
sharper the break angle:
Here's the deal: all the string energy's transmitted through the saddle right at the point of contact, and the
sharper the break angle, the more string tension (energy) and vibration is transmitted
through the saddle and bridge to the top.
Of course there's a range of acceptable
saddle height, but over the years makers have come to a fairly common agreement that the ideal height of the
bridge and saddle combined is in the neighborhood of a 1/2"; that allows for the optimum transfer of energy to the top yet still allows acceptable action at the 12th fret.
Of that 1/2" typically the bridge is around 5/16" and the saddle around 3/16"
above its slot.
Again those are just "ideals" that are tailored to each guitar according to its neck set angle.
When the saddle's installed it's typically given a height to yield the "action height" of clearance from the 12th fret on the bass E string.
Guild's action height for US-built guitars in the '90's was 6/64 on bass and 5/64 on treble E.
Another member with much wider experience in various brands than myself recently mentioned that's actually a pretty common spec in the industry and I suspect an MIC Guild would use it, as a good general purpose starting point for an individual to tailor to their taste.
Anyway, lowering the saddle
does reduce the break angle and thus does have some effect on volume, but as I mentioned, it's normally not so large as to be as noticeable as you seem to perceive.
The formula to lower the action height is to remove double the amount from the saddle as you want to lower the action at the 12th fret , ie, if you want to lower the action by a 64th you must lower the saddle by a 32nd.
And that in itself shouldn't be a major impact on a saddle with an ideal 3/16" height, but if the saddle is lower than 1/8" after lowering, then yes it probably has a very poor break angle and I'd expect volume
would be noticeably impacted.
Ok, having explained that, let's get back to your primary concern:
Playability
A lot of folks don't realize how much the nut slot depths affect "feel" especially down at the first 3 frets, but that's also an area a good luthier checks when giving your guitar a personalized set-up.
Making those slots just a tiny bit deeper can have a sizable impact on playability on up the neck even, so suggest looking into that, too.
Here's a great site with more info by highly respected luthier Frank Ford of Gryphon Instruments in Palo Alto CA:
http://frets.com/FretsPages/pagelist.html
About saddles:
http://www.frets.com/FretsPages/Musician/Guitar/Setup/Saddle/saddle01.html
About checking nut slot clearance:
http://frets.com/FretsPages/Musician/GenSetup/NutAction/nutaction.html
Now you can converse with a luthier intelligently.
:smile:
I suggest having luthier do nut slots if you do decide to get 'em fine-tuned, because the tools (slot files) are expensive and you'll undoubtedly wind up going through at least a couple of blanks while getting the hang of it.
Also, getting an actual Guild saddle blank isn't necessary: most anybody (luthier) can fashion a new saddle from a blank of the proper thickness.
But those guitars did have bone saddles (and nuts) and I suggest sticking with that material, bone's got a good reputation for tone.