The guitar saddle is the strip of hard material set into the bridge that lifts the strings to their appropriate height and angle. It is important in the production of tone because it is the terminus of the suspended strings, transferring the string vibrations into the wooden bridge and the resonant body of the instrument itself. It acts like a filter, depending on what it is made from, enhancing certain frequencies, muting some others, while letting others through unchanged. Not every guitar reacts to every saddle material in the same way. But saddles made from bone are a popular choice and with good reason.
A guitar saddle made from polished animal bone provides a singular purity to the sound waves passing through it and helps a guitar achieve optimum clarity, volume and sustain when it converts that energy into audible tone. If you have a saddle of some inorganic material designed to mimic the effect of bone you would likely be better off switching it out for the real thing.
The one exception to this would be a guitar that is overly bright and brittle, like guitars made out of maple or those with a brand new, Adirondack spruce top. In such cases you might be better off with a saddle made from fossilized walrus ivory. This material is quite different from elephant ivory, which sounds almost exactly like bone to my ear and is therefore not worth the expense nor the guilt. FWI saddles are not just good transmitters of sound waves, they actually alter them to provide added warmth and thickness to the guitar's voice at the expense of losing some of sparkle in the higher registers. But for most guitars bone is a fine way to go and it is the first choice of the world's best luthiers.
I was frankly astonished at the difference in the voice of my 1997 Martin OM-28VR when I had the stock Micarta saddle replaced with one made out of bone. Prior to this switch I had assumed any saddle changes would be hardly noticeable. I couldn't have been more mistaken. The increase in volume was immediately apparent, particularly when stressing individual notes by hammering them with a fretting finger or digging in with a pick for extra emphasis. But it was the change in the tone that really won me over.
Actually, I was initially put off by the sound of my first bone saddle. I have since come to learned that brand new bone saddles can have a shrill quality in the upper range of the treble. But this only lasts a short time. Once this saddle has been played in a while that abrasive edge burns off and what remains is a glassy clarity that simply can't be found in saddles made from materials like Micarta or Tusq. The wound strings on my OM-28VR have wonderful definition that give a detailed rendering of the fundamental note without compromising any of the smoky, Martin undertone. The unwound treble strings just make me smile and shake my head when I hear how beautifully pure they sound and how they stay that way as they hang there in the air until they slowly fade away. For my money any guitar made with a Sitka spruce top would be enhanced with the addition of a bone saddle.
A bone saddle may be good at making great guitars exude their full potential, but they make budget models sound so much better as well. Since my guitars already have bone saddles I took the saddle I recently acquired from Maury's Music and had it installed in an OM-sized Ibanez belonging to one of my best friends. This laminated mahogany guitar benefited tremendously by the addition of bone. I had already installed a set of bone bridge pins that perked up the voice a lot. But the bone saddle increased the volume, definition and sustain to the point that it sounded like a much better guitar than the one he walked out of the store with.
Even if your guitar already has a saddle made of bone you might still benefit greatly if you exchanged it for a new, compensated bone saddle. Because a set of guitar strings is made with different thickness and each string breaks at different angles when fretting up and down the neck it is impossible to achieve perfect intonation on all strings at all positions. A customary way of compensating for this is to have the saddle carved so some strings break across it at slightly different distances. In effect this makes the playable "scale" of each string slightly longer or shorter so they are as close in intonation as possible. The B string is the most noticeable when it comes to this so it is the string needing the greatest compensation. Some guitars require the compensation to be fined tuned by further shaping the saddle, but most will work great with a compensated saddle just as it comes from the dealer.
Fortunately many guitar makers are now using bone saddles in their stock models. But not all of them come compensated. If you are a player who rarely brakes away from strumming Hank Williams chord progressions down at the first fret you may not need to bother with a compensated bone saddle. But if you play up the neck at all or your music features melodic structure or a lot of sustained notes, fingerstyle patterns or chord voicing that take advantage of octave parings or the harmonic potential stretched out across the fingerboard then I would think a compensated bone saddle can only enhance the sound of your guitar, no matter how much your guitar cost or how old it may be.
Out of a possible 8 Notes on the T Spoon Scale of Guitaracity I give the Compensated Bone Saddle a polished and pure 6 Notes.