Instructables

Adjustable Bridge

I have an Epiphone acoustic guitar that I really like, my girlfriend gifted it to me after her uncle gifted it to her (she doesn't play, fingers are too small). It's the FT-130. It basically has two large screws, one on either side of the bridge, If anyone is familiar with this style of adjustable bridge can you please either tell me how to use it or send me a link to a site that will? the action is pretty low on the high strings and I'm getting a lot of buzzing (more than I should). Thanks for any help you can give!

Berkin5 years ago
Something's loose, it sounds like.
korondot5 years ago
I recently received an old acoustic from my uncle i was so excited my mother told me that pratice would be painful and give me blisters but i didnt beleive it until a few weeks of pratice so i got the thinking maybe i should give up guitar im not man enough come to find out the previous owner of the guitar glued the bridge back on(unevenly) after it had come off it was a slapdash job and because of this fretting is difficult and requires to much effort the strings are raised off the fretboard any way to perform a DIY repair without caused further damage
gmoon6 years ago
I believe it's just a height adjustment, and not intonation; so messing with it shouldn't be difficult. Simply loosen the tuners a bit, figure which direction is which (up or down), then adjust the screw in 1/4 turns until it you're satisfied....

Here's a forum link on the subject. Based on this, it does appear that many are set too low...
Exitao gmoon5 years ago
It is definitely about height adjustment. The first response was absolutely correct. The action is measured at the bridge and the 12th fret and it's rare that adjustments are ever made at the nut

I study flamenco guitar, but I started using a classical. The action on a classical is significantly higher than on a flamenco, so I got out the sandpaper and sanded down the saddle at the same time I attached my tap plate. See this link for a classical/flamenco set-up by a luthier; you'll see pics of him sanding the saddle. http://www.fernandezmusic.com/ClassicalGuitarSet-up.html

Clearly if you lower your action too much, you will get extra buzz, more than just from poor fretting. It's tricky too, because if you sand it too much, you need to get another piece of bone (happened to me). But a lower action can provide a quicker response, especially with the kind of attack required by flamenco. I have no idea why they would bother on that kind of guitar, unless they're also popular with fingerstyle musicians.
I actually googled your guitar and found a bunch of reviews on one page - read comments about the action, to see confirmation that I'm not deceiving you.
http://reviews.harmony-central.com/reviews/Guitar/product/Epiphone/FT-130/10/2

That's not a problem with your epiphone, you just adjust screws to your liking. However, so people would suggest that because the saddle is supported in part my those screws, you are losing sound quality; vibrations should travel through the strings, through the saddle, through the bridge and into the sound-board, amplified by the resonance chamber... Your saddle is likely not in full contact with the bridge, but it's factory made so you're probably not missing out on much anyway...
ravenx996 years ago
You can adjust the action (distance between the strings and fretboard) by changing the height of the saddle. In traditional acoustic guitars, this requires either sanding down the saddle (to lower the action) or installing a taller saddle (to raise the action). Lowering the action makes the strings easier to press to the frets, but too low produces buzzing. Most factory guitar "settings" produce an action that is too high for comfortable playing. The action can be changed when you adjust the neck of the guitar by means of the truss rod, but changing the action is not the truss rod's purpose (despite an earlier comment). The truss rod adjusts the bow of the guitar's neck against the tension of the strings. Adjusting the bow changes the action as a side-effect, but adjusting to change the action this way can result in an incorrect bow. The action is also affected by the height of the nut, where the strings leave the neck to the tuners. Like the saddle, action adjustment at the nut requires filing the nut down or replacing it with a taller one. But you only need to adjust action at the nut if the strings are not the desired height from the bridge at the first few frets... a high nut can make the first fret very hard to play.
ravenx996 years ago
Did you ever find a good answer to this question? I have a Korean-made Harmony that clones this adjustable bridge and it's not clear to me how it works either. (Gibson nuked and restarted their forums, and archive.org doesn't have a copy, so the above forum link doesn't produce any information on this topic.)
And it turns out that all of the comments after the very first one are irrelevant. Just turn the screws to raise and lower the saddle.
NachoMahma6 years ago
. See page 19 of this PDF, courtesy of Gibson/Epiphone.
A decent document, but unfortunately this isn't a tune-o-matic bridge (see pic.) Those are only used on electrics, and require a separate tailpiece--also lots of solid structural wood underneath. Even on "semi-hollow bodies" there's a solid chunk of wood running down the center of the body.
N_LPfeat6.jpg
. Sorry about that.
Well, this appears to be a pretty rare bridge (and was discontinued some time ago.) Not an easy thing to track down. Still, looks like a height adjustment, and not intonation. Don't see how HAL 9000 could mess up the sound much by adjusting it.... Bridge height (if easily done, as in this case) would the first thing to try, anyway, if it was "fretting-out." (the link I gave below has since been redirected by Gibson, and doesn't seem to have any pertinent info anymore...)
. I've seen that bridge (from the original post) on guitars, but I can't find anything about it on the Web. It looks to me like turning the thumb screws would adjust the height. . I'm no luthier, but, like you, I don't see how you could set intonation with that bridge. . BTW, everything I read on bridge adjustments said to loosen the strings before adjusting. . . OT question: Why do I seldom (if ever) see intonation adjustments on acoustic guitars, yet it is common on electrics?
RE, acoustic vs electric:

--Thicker strings tend to be closer to the ideal (once the thickness itself is compensated for--the angle of an acoustic bridge.) Acoustics usually use .13 or .14 for the high E, vs. .09 or .10 for electrics--some even use an .08. With thinner strings the difference between the wound and unwound strings is bigger, too.

You'll see a lot of archtop electrics with a straight bridge (or "fixed" compensation)--jazz players use heavy strings, too.

--You tend to play more up the neck with an electric; the farther from the nut you play, the more incorrect intonation becomes obvious.

--With poor intonation, the "beats" you hear playing multiple notes (in unison, or intervals) sound retched. It's the effect you get when overlaying two nearly identical sounds are just slightly out of tune. With lotsa volume and distortion it's pretty bad....
. Thanks
arhodes186 years ago
well from what i know about it you adjust the neck not the bridge. this is called a raise action, i get mine adjusted at the shop. the buzzing sound is called fretting out btw. you can do it on your own though by finding an allen wrench screw on the neck (called a truss rod) this will probably be on the inside of the sound hole just visible at the base of the neck. it may also be on the headstock concealed by a cover. once you find it you have to find which way to turn it. be careful not to over adjust it though.
Wario6 years ago
Great question, nice guitar