PDA

View Full Version : Bridge adjustment tricks



nf_arkie
Aug-13-2007, 10:20am
Howdy all,

After playing my Rover following a restring and set-up adjustment for better action, I felt like the tone had actually suffered a bit - it was kind-of plucky sounding, especially the G strings. So remembering that bridge height can affect tone, I started playing with bridge height to see if the tone could be improved with minor adjustment.

Immediately upon raising the G side, no more than a half turn, tone and sustain improved. But the ring in the E side deminished as well. So I raised that a smidge to see what happened. Well, this went on (back and forth) for a while with improvement and decline of varying degree. And the sound I was hunting for seemed to be directly affected by the relative height of the E side to G side.

I finally got the E,A, & D strings to ring pretty well up the neck, but the G falters around the 8th fret - sounds a bit dull and plucky from there up.

BTW - the action on boths sides is almost exactly 2mm at the 12th fret, and much lower seems to put it right on the edge of fret buzz when you attack the G strings more aggressively. The bridge is set slightly higher on the G side; string height at the bottom of the slot is roughly 2.1 cm compared to 1.95 cm on the E side. Also the bridge appears to cant forward (from perpendicular) slightly more on the E side, maybe 1-2 mm.

Is there a "science" to this bridge adjustment thing, or is it more of an art? Is it to be expected that an adjustment up or down on one side will necessarily affect tone across the entire bridge, and is it predictable?

Any thoughts appreciated.

Thanks - JP

mandopete
Aug-13-2007, 10:38am
Is there a "science" to this bridge adjustment thing, or is it more of an art?
I think that placement of the bridge with respect to intonation is the "science". #It's pretty easy to do with a tuner. #If the 12th fret harmonic is flat compared to the 12th fret "fretted" note the bridge need to move away from the nut, if it's sharp them move towards the nut.

Action is the "art" and one that I still have not fully come to understand. #I believe that neck angle plays a big part in this. #I have been fiddling around with the bridge on my Collings for at least 6 months now by going down maybe a 1/2 turn on the wheel and then playing it for a month or so to see if I like it. #For the life of me I can't really tell the difference. #All I know is that when I play someone else's mandolin it seems like their action is lower (and easier to play) than mine. #I'm at a loss to understand - maybe it's just all in my mind <grins>.

otterly2k
Aug-13-2007, 10:51am
Yeah, the action is always lower on the other guy's mando.

Didn't Aesop write about that?

billhay4
Aug-13-2007, 11:00am
Try this page: Mandolin Action (http://www.fretnotguitarrepair.com/Mandolin_Repairs.htm)
Bill

earthsave
Aug-13-2007, 11:25am
Bridge fit on the top is important to the sound as well. Make sure your feet are fully in contact with your top.

2mm seems kind of low at the 12th fret. But if it dont buzz then I guess it'll make for easy pickin.