Mother-of-Pearl nut?

[Richard Mott]

Dear Luthiers—In the acoustic guitar world, nuts are at least in my experience almost exclusively made of bone. (By contrast, bridge saddles on flattop guitars vary from bone to ivory, to fossilized ivory, and synthetics ... but almost never wood.) Whereas in the mandolin world, bridges are wood and mother-of-pearl is sometimes used for nuts, at least in higher-end instruments. Likewise, in some archtops (Monteleone, Gilchrist) one also sees mother-of-pearl nuts. Is there a sonic or tonal reason for mandolins (and archtops) using pearl as a nut? Or is it more a matter of tradition? And is there a clear reason for the mandolin’s divergence between bridge (wood) and nut (pearl), versus flattop guitars where bone is typically used at both nut and saddle? Any light you can throw on these choices is much appreciated! —Richard

[sunburst]

...one also sees mother-of-pearl nuts. Is there a sonic or tonal reason for mandolins (and archtops) using pearl as a nut? Or is it more a matter of tradition?

It's the latter.

And is there a clear reason for the mandolin’s divergence between bridge (wood) and nut (pearl), versus flattop guitars where bone is typically used at both nut and saddle?

Tradition again.

Now, there will be quite a bit of disagreement on these points. Some claim to hear a difference in nut material and claim that pearl sounds better, or that bone sounds better. (But then some people claim to hear a difference in the size and plating of ligature screws on saxophones!) There may be a subtle difference in sound depending on saddle or bridge material, but my bet would be that a double blind listening test would not show conclusive results. It would be interesting to have such test results but it won't happen in all likelihood.
Pearl can be more durable as a nut material, but it can also be prone to chipping. I prefer to make nuts from bone because it is a friendlier material to work with compared to pearl, but I use pearl also occasionally.

[Charles E.]

As to the bridges for guitars and mandolins, they are two different beasts. The bridge on a guitar is glued to the top with a saddle embedded into it. I requires a material as durable as bone to make it work. With mandolins ( and arch top guitars ) that is not necessary, the entire bridge and saddle can be made from ebony. There are instances where mandolin bridges have been made entirely of bone or a combination of an ebony base and a bone top but these tend to be seen on older bowl back mandolins. Heck at one time Gibson made bridges with Aluminium saddles on ebony bases.

[Ray(T)]

My understanding was that strings tend to bind less on MoP nuts but I can’t remember where I heard it.

[rcc56]

Many kinds of materials have been used for guitar nuts. Martin has used ivory, ebony, and various plastics. I believe they currently offer bone on some models. Gibson has used ebony, bone, and various plastics. Around 1980, brass guitar nuts were somewhat popular. I generally use bone in the shop unless someone requests something else.

I changed the plastic nut in a Seagull guitar to bone, and there was a moderate improvement in tone and sustain. Since it was a personal guitar, I swapped the two nuts back and forth several times just to make sure the change was real and not just wishful thinking.

I have seen one piece mandolin bridges made of ebony, rosewood, maple, and ivory. I've seen them with a metal fret or an ivory or bone saddle inlaid. I've seen adjustable bridge bases in rosewood and ebony with saddles of solid aluminum or ivory. I've inlaid bone into an ebony mandolin saddle with good results.

Nuts, bridges, and saddles are a part of the instrument we can play with. In my experience, the tonal differences are usually only slight to moderate once you get away from cheap plastics. Getting rid of cheap plastics can make a bigger difference.

Since the availability and expense of really good quality ebony and rosewood is becoming a problem, guitar makers are starting to experiment with alternatives for flat top guitar bridges. Any dense, stable wood should work. Since the market likes dark woods, it would be desirable to stain a guitar bridge made of hard maple.

I once made an aluminum nut for a Loar period F-4 at the owner's request. He liked it. That was almost 20 years ago, and the last time I asked, that nut was still on the mandolin.

[MikeEdgerton]

A few years ago I had the nut on my F5G changed to pearl. I did it because I like the way it looked. The mandolin already sounded good to me.

[j. condino]

Mammoth ivory....the purple colored has a better "chop" than the yellow.......

[Ray(T)]

I remember the brass nut fad that rcc56 mentions. People did it because they thought it increased sustain. Frets magazine investigated it and concluded that it was true but it was down to the increase in weight at the end of the neck and even better sustain could be obtained by simply screwing a G clamp on to the head; a much cheaper solution.

[William Smith]

I remember changing the bone nut to pearl on my old 30's F-7 conversion and it took awhile to get the same tone back! That also could be from breaking the bridge contact from the top? I know when you take a bridge off it'll take awhile to settle back in! Pearl looks great and its tradition on most all old F-5's that are original.

[Richard Mott]

Thanks everyone, for the helpful insights. (Especially James, for the purple/yellow mammoth ivory chop info!). It sounds like tradition for mother-of-pearl nuts may be a good part of it, but equally m-o-p is an attractive and well-suited material, maybe even helpful in avoiding strings binding up as sometimes happens. On the use of bone and ivory saddles in flattop bridges, it occurs to me that the torque in a flattop bridge, which is pulled up by the strings and over the saddle in a very tight space may result in considerably more force than the simple downward pressure of strings on a mandolin or archtop bridge. If so, that may require materials like bone or ivory less likely to fail under pressure. Anyway, thanks everyone for your input!

[William Smith]

So in the past I've seen bone or ivory saddles on traditional F-5 Loar style bridges-Does that brighten up a woody/bass type mandolin? I've never experimented with that type of configuration?

[j. condino]

The ones that I've made seem to emphasize the high end more so they appear brighter with bell like clarity, sometimes too much. They remind me of what it is like when you remove a Loar style tailpiece and replace it with a heavy brass Monteleoene style- you definitely get more highs but the overall sound shifts towards a slightly different voice. 'Great for folks who only change their strings once a decade. In the end I always went back to an ebony saddle and liked the overall increased harmonicity by just keeping the strings fresh. A bone saddle can be useful when a top is thinned too much and the high end drops off, like some mandolins that have a giant chop, but there is no treble response until you get around the 7th fret.

Get ready for three dozen half deaf old geezers to start a flaming argument about what you can and cannot hear....."d@mned kids....'whole lotta nuthn"....

[pops1]

Get ready for three dozen half deaf old geezers to start a flaming argument about what you can and cannot hear....."d@mned kids....'whole lotta nuthn"....

I resemble that remark.....

[Rob Roy]

My only experience with MOP nuts on a mando is one I tried to repair for a friend/customer. On that particular nut, the skinny areas between the courses and on the outside of the E string were weak and chipped. I had to try to cobble together a workable fix with a chunk of the nut missing so he could gig with it that night. Luckily, I was able to file the slot a few thousandths lower and that held the E string in place. I prefer bone, you just have to get the slots right and lube with graphite.

[William Smith]

Well on the bone or ivory saddle I'll have to ask my Uncle Gene Johnson as his stints and recordings with Cliff Waldron and the New Shades of Grass in 1972 and with the II Generation after his tone changed on his Loar F-5 because in the archive he was shown playing with JD Crowe and the New South and he either had a bone or ivory saddle on # 75305 as I have a few fest cd's that were made with him with that season playing and singing tenor with JD. and Keith Whitley and his Loar sounded mighty fine-different than his previous recordings? Really great!! "They" haven't released any recordings yet with Uncle Gene with Crowe!!

[Nevin]

I have an electric guitar with a brass nut. It has more sustain then any other electric guitar I have played, even unplugged, but I don't know how much of that is the nut, the bridge, the body or neck wood, etc.