Members Michael Martin Posted January 18, 2007 Members Share Posted January 18, 2007 I've been GASing over, of all things, an older Epi FT model (from 70s) that has an adjustable bridge. Which raises the issue: why aren't these (adjustable bridges) common on acoustics? They're the norm on electrics...at the very least, such a bridge would vastly simplify the process for bridge height adjustment. The Epi sounds really good and the adjusters still work...so what's the reason? (I'll bet Freeman has something to say about this?) Link to comment Share on other sites More sharing options...
Members Freeman Keller Posted January 19, 2007 Members Share Posted January 19, 2007 You are talking about one of these, right? Here is what Frank Ford said about them "Each little saddle insert may be adjusted for optimum intonation correction. This is a swell idea from the standpoint of tuning. Just "dial in" each string, and the job's done! The only problem is that, tonewise, it sucks. The massive brass and steel hardware is a very effective mute, literally impeding movement of the bridge by the vibrating string. More of the string's energy is "reflected" back on itself, and dissipated as heat, and a bit more vibration of the other anchor point of the string (the peghead.) If you doubt this effect, sit and play an unplugged solid body electric guitar sometime. You'll easily be able to hear the peghead vibrating." Freeman's thoughts: Remember that the big difference between an electric and an acoustic is that the string drives the saddle which vibrates the top (you never hear the string itself) and the old bone saddle seems to be a pretty good way to achieve that. I've been reading Roger Siminoff's book on tap tuning lately and have come to realize that the bridge/saddle on a fixed bridge guitar (normal old pin bridge) actually "rocks" the top to make it vibrate, while a floating bridge (like an archtop) has a vertical component of the strings vibration into the top. That is why an archtop has two wimpy little tone bars and your Martin has the big old X brace. One thing that I have always wondered about, however, is why we don't see more of two piece saddles like this (but without the pinless bridge) Thanks for asking Link to comment Share on other sites More sharing options...
Members Treborklow Posted January 19, 2007 Members Share Posted January 19, 2007 I personally like them for the easy adjustments, but some of the Gibson adjustable saddles were made of a ceramic material that did not transfer the string vibrations very well and they sounded a bit odd. Even the wood ones didn't transfer sound as well as a tight fitting bone saddle. That is probably the main reason most makers don't use them. I suppose the best sounding guitars have a fixed saddle that has been height adjusted. Link to comment Share on other sites More sharing options...
Members Freeman Keller Posted January 19, 2007 Members Share Posted January 19, 2007 I'll add a comment that on another forum someone asked how to eliminate the adjustable bridge. I suggested filling the hole left when it was removed with a nice piece of rosewood or ebony and routing a slot for a nice bone saddle, properly compensated. Several people chimed in to say that was a good idea. I've never dealt with one so I really don't know. Link to comment Share on other sites More sharing options...
Members drnihili Posted January 19, 2007 Members Share Posted January 19, 2007 One wonders whether modern technology might not come up with a solution to the problems noted by Mr. Ford. Link to comment Share on other sites More sharing options...
Members J. Posted January 19, 2007 Members Share Posted January 19, 2007 I remember a little adjustable saddle called the "grandaddy" or something like that. Musician's Friend used to sell it as an aftermarket replacement part a handful of years ago. Link to comment Share on other sites More sharing options...
Members Terry Allan Hall Posted January 19, 2007 Members Share Posted January 19, 2007 I'll add a comment that on another forum someone asked how to eliminate the adjustable bridge. I suggested filling the hole left when it was removed with a nice piece of rosewood or ebony and routing a slot for a nice bone saddle, properly compensated. Several people chimed in to say that was a good idea. I've never dealt with one so I really don't know. I've repaired a bunch of 'em...putting in a solid saddle really woke up the tone in every case...adjustable bridges lose a lot of bass. BTW, you can buy drop-in compensated replacements made of bone or rosewood. Link to comment Share on other sites More sharing options...
Members Freeman Keller Posted January 19, 2007 Members Share Posted January 19, 2007 StewMac sells a little gizzie that is supposed to help get the saddle located and cut right on a conventional drop in, I've considered buying it each time I make a new one The Intonator Link to comment Share on other sites More sharing options...
Members Michael Martin Posted January 19, 2007 Author Members Share Posted January 19, 2007 Actually, the bridge on the Epi is not one that has adjustments for each string--There's one saddle for all 6 strings with thumbscrews on each end. I have an old bass (Japanese EB-3 copy) that has the same kind of bridge. But thanks to all for the info. Link to comment Share on other sites More sharing options...
Members Freeman Keller Posted January 19, 2007 Members Share Posted January 19, 2007 Oh, so you mean like an archtop or a mandolin? They are adjustable for height with the little thumbscrews and the intonation is set by the way the saddle is notched. They usually just sit on top of the top and can be moved back and forth to tweek (or screw up) the entire intonation. I alluded to the big difference between a fixed (pin type bridge) and a floating (archtop) bridge in my first comments. As the string vibrates it is alternately stretched and relaxed (yes it is going up and down too) but with a fixed bridge the energy of the stretching is transmitted to the top by the string "pulling" and relaxing the bridge and bridgeplate. It actually rocks the top using the top of the saddle as a fulcrum. Some energy is transmitted thru the saddle, some thru the ball ends of the strings up against the b/p. But basically, all of the string's energy goes into the top at the bridge (it has to). On a floating bridge, the string is still stretched and relaxed (as well as moving up and down). Much of the energy is transmitted to the trapeze tailpiece (and to the rigid end block), but there is a component that goes into the bridge and vibrates the top. In the case of the floating bridge, it moves up and down, not rocking the top. The energy is much less, so the top does not have to be braced as rigidly. Most archtops (and mandos and violins) only have the carved top and one or two tone bars (which aren't there to strengthen the top as much as tune it). Violins have their little sound posts and one bar. Anyway, the whole thing is brace much lighter because the forces are much less. As an aside, that is why the steel string X brace was developed - the rocking of the top needs to be controlled, yet the top need to be free to vibrate as a drum head. OK, to make a short story long, that type of bridge would work if the top was designed and braced accordingly Class dismissed Link to comment Share on other sites More sharing options...
Members SpaceCowboy409 Posted January 19, 2007 Members Share Posted January 19, 2007 My first good acoustic was a '65 Gibson Dove with the bridge that Freeman Keller's top photo shows. It really wasn't a very good sounding guitar. Link to comment Share on other sites More sharing options...
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