1. I Am Your Anchor; I Am Your Rock.
Which is to say, solidity is important. This is the body-end termination point for your strings’ speaking length, and their vibration needs to pass through the bridge to get into the tonewood in the body. Therefore, the quality of the body’s resonance is going to be in great part determined by the composition and quality of the bridge (and tailpiece, if they are separate units). For that reason, the bridge is an essential link in the tone chain, ranking right up there with your guitar’s pickups and the wood the body is made from in setting the core tone of the instrument, especially if you want to hear deep, harmonically rich resonance throughout the body of the guitar. As such, the bridge’s solidity also greatly affects sustain.
2. Lightly Coupled Set-Ups Can Be Useful in the Tone Equation.
Less-than-rocklike bridges can also contribute positively to the signature tones of several seminal guitars. For example, Gretsch guitars mounted with a Bigsby B3 or B6 vibrato tailpieces—which lack tension bars—will have fairly low string tension over a floating bridge, and the relatively light coupling of this setup is an important part of the jangle content in “that great Gretsch sound.” Similarly, Fender Jazzmasters and Jaguars are made with vibrato units that present low string tension over moving “rocker” bridges. You can buy a device to increase string angle over the bridge, and therefore tension, which the maker purports will “improve tone,” but the only certain thing is that it alters the tone. Many fans of these guitars will tell you such an alteration robs the instruments of some of their distinctive sonic character.
3. Composition Affects Tone.
Bridges and bridge saddles made from different materials resonate differently, and therefore make your guitar sound different. Stamped steel (’50s and ’60s) and die-cast Mazac (’70s) Strat bridge saddles sound different; brass, threaded steel, and notched steel Tele saddles sound different; chrome-plated steel and nickel-plated aluminum wrap-over bridges sound different; floating bridges made from rosewood and ebony sound different; and so on. Tonehounds will venture opinions as to which sounds better, but the only sure thing, objectively speaking, is that changing from one type to the other will change your tone slightly.
4. You Won’t Play in Tune If It Isn’t Set Correctly.
The adjustable element of your guitar’s intonation is set right here, and if you don’t get it right, you’ll never quite play in tune, no matter how accurately you tune up. Guitars with three-saddle Tele-style bridges, wrap-over bridges, and singlesaddle floating bridges offer less and lesser abilities to fine-tune intonation, but Tuneo- matic bridges and Strat-style vibrato units and their derivatives provide excellent facilities for precise adjustment. This is also where string height is set, so it’s critical to any proper setup in several ways.
5. The Bridge Is Crucial in Determining a Guitar’s Feel.
In addition to all of this, different bridges can make guitars feel different to play. Although the tension required to bring strings of the same gauge up to pitch is the same, those strung on a Strat-style vibrato or a Bigsby unit will have a slightly looser, spongier feel and be easier to bend than strings on a wrap-over or Tele bridge or similar. This is because the springs in the vibrato unit offer a little “give” when you push the strings, and the added string length behind the bridge saddles contributes to this feel, too.