Bridge Pins…Really Make A Difference?

[Wadcutter]

Originally Posted by Herb Hunter

You have no reason to apologize. Arthur Slowhand doesn’t appear to have considered that we may have new members who are unaware of past discussions or have something new to add to the subject such as new research or fresh opinions from experts.

Thanks Herb, I appreciate that.

[Alan Carruth]

Originally Posted by Knives&Guitars

For now, I will stick with my ears and logic. If I am fooling myself...then I have also fooled some very credible Guitarists-Lutheirs as well.

I don't think you have logic on your side in this case, and since I know how easy it is to fool my ears, I've got to assume your ears are subject to the same problems. Luthiers are as easy to fool as anybody, especially when there's a large body of time-hallowed myth to back it up. A lot of the experiments I've done were aimed at those myths: "It's not the stuff you don't know that gets you into trouble, but the stuff you do know that isn't so". The hardest beliefs to counter are the ones that 'everybody knows'.

The way I see it, the 'job' of the bridge is to tell the string how long it is, so it will know what note to make. The actual termination of the string at the saddle certainly matters, and the density, hardness, and stiffness of the saddle material could be germane (although that might be hard to test out), but nothing behind the top of the saddle should have any effect unless it alters the way the top vibrates. It's easy to show that even small changes in mass, as little as a couple of grams, can do that, and the difference between a set of plastic and ebony pins can be a couple of grams. If anything behind the saddle does affect the sound it's a sign that the saddle isn't doing it's job. Of course, the bridge/saddle on an acoustic guitar can't be absolutely immobile; if it were the guitar would produce no sound, but any vibration of the string behind the saddle has to be minimal.

Most of the power driving the top comes from the vertical polarization of the transverse wave in the string: the string moves 'up and down' relative to the soundboard plane and pulls the top along with it. This is the vibration that really has to pretty well stop at the bridge; when it doesn't you get 'wolf' notes and intonation issues.

The tension in the string also rises and falls twice per cycle, pulling the top of the saddle toward the neck. This introduces some second partial to the signal, but not a lot of power. It's an ineffective way to produce sound, since half the lower bout rises as the other half falls. The top is deliberately made stiff in that sense, so it won't fold up, and you don't get much motion for a given force, particularly at low frequencies (below ~F on the high E string, 1st fret).

The actual force this 'tension' signal develops averages only about 1/7 of the vertical 'transverse' force, so there's not much power there. It's possible that some of this force could get past the saddle top to the top of the bridge, where the string bends down along the pin, but friction between the string and saddle top, and the string and the bridge, should eat up most of the tension signal before it gest down to the bottom of the pin.

There is also a high pitched 'zip' tone, that drives the bridge in much the same way as the tension change force. It varies a lot, and comes and goes in the string signal because of the way it's driven by the string vibration. It suffers, of course, from all of the inefficiencies the tension signal does, and probably has less power overall, but it is normally dissonant, and high pitched, so it's very audible. In my 'height and break angle' experiment I suspect that this was most of what people were picking up in the listening tests. Again, it's just possible that some of this could be transmitted to the bottom end of the bridge pin, If that's the case it would be easy enough to come up with a test setup that would show it. Having had some experience in this sort of thing I'd be happy to advise anybody who wanted to do it on ways to go about it, but I sure don't have the time to actually run the experiment myself.

Even if you found some signal at the bridge plate you still have to come up with a mechanism that converts that force into sound, and show how the pin material alters that. The first thing to do is when you want to explain something is to be certain there's something that needs to be explained. Find that signal.

[AcousticDreams]

Originally Posted by Alan Carruth

If it's simply based on your own impression of the sound then I am skeptical.

Originally Posted by Alan Carruth

I don't think you have logic on your side in this case, and since I know how easy it is to fool my ears,

You offer such a wealth of information Alan. You have most certainly expanded so many interesting concepts of how sound comes out of a Guitar. I have not doubts that many of your theories offer great relevance and have reasonable credibility.

But for now, Unless you tell me you are working with NASA, I shall also be a bit skeptical of the methods you have used to determine your results. While I wholeheartedly believe in Science....I also know how easy it is to make mistakes in how we conduct experiments.

Ultimately, I am Not saying you are wrong. The one thing I have learned in life is that most anything is possible.

However, ]what I would like to ask is why you feel so determined to point out each time that you are Skeptical? Or How people can be so easily fooled?]

Very honestly, you could be right. I only offer my personal observations. But isn't that what the AGF is all about? Personal observations?. Do we need to always hinder peoples personal observations by discrediting them because they do not meet the Scientific experiment requirements you would like?

If we totally negate the possibility of something by constantly reinforcing the skepticism, then maybe we will stifle that one person who will have the time some day, and correct equipment to properly do an experiment. As they will think there is no reason to even go there because someone else does not believe it.

I have learned, so, so, much from the AGF just based on peoples personal observations. It has expanded my world of tonal possibilities and I am grateful.
I have also been dubious about many factors myself. I am not innocent in this area. The difference is I did not speak out against someone else's claims. I might have offered other observations in regards there of..but with out discrediting.

Things like Pick materials, nut and saddle materials, I heard over and over again as to them making a difference . When I heard so many others claims, eventually I say " why not give it a try...it will only cost a little to find out" . Personal observation is the foundation which leads to scientific experiments.

Science is great. But so is personal observation.

[TDavis]

I’m not sure to what degree bridge pins change sonic properties…but I have often swapped Martin bridge pins simply because the thought of using plastic pins on a $3000+ guitar offends my sensibilities. I will admit though, that I have a very insensitive aural palate.

Funny thing though, I’ve gotten my share of pins from Bob Colosi…and Bob is so forthright that he will flat tell you what his products (pins, saddles & nuts) will change tone-wise…and what only look better. Haha!

[RogerHaggstrom]

Before I even start, I'm an Alan Carruth fan. I have a folder on my hard drive with a lot of text files with his snippets of guitar wisdom's I like to re-read now and then. But I have to disagree on this topic.

Weight matters in saddles and bridges. But also the saddle and bridge frequency filters that filters the full frequency spectrum coming from the strings. The material in the saddle and bridge will bounce or let pass different sets of frequencies from the strings, and thus changing the "tone" of the whole guitar.

I do one-piece segmented saddles with bone posts under each string and glued in soft wood replacing the voids between the bone posts. Spruce or cedar between the bone posts gives the guitar different tones, the cedar wood gives a "darker" tone compared with spruce. The very small difference in weigh of the segmented saddle can not explain that change in tone.

Also, the hardness of the bridge and the materials connected to the string matter. In my test guitar, I can replace a sliver of wood between the top and the underside of the saddle (the saddle ditch is actually an elongated hole through the bridge). Again, not a big change in weight. A spruce shim will dampen the volume and trebles, a really hard wood will do the opposite. The different hardness of rosewood and ebony is a major reason ebony bridges sounds a bit hard and sharp and rosewood a bit mellow in comparison (I like the sound of a rosewood bridge better).

I use spruce in my bridgeplate, not a hardwood. With spruce, I always get better dynamics and a better overall sound. I think the common maple bridge plate makes it hard to hear the sometimes subtle changes that come with different materials in the bridge and saddle.

When doing spruce bridge plates and the segmented saddle with spruce between bone posts (with a button of hard wood around the stringpin hole in the bridge plate to withstand the wear from the string's ball ends), I get a very mellow, beautiful and rich tone, but also low attack and volume. You can not be angry with the guitar with this setup, everything you do is nice sounding.

To counteract this not so pleasing behavior, I use harder wood plugs to connect the bridge plate hardwood button with the underside of the bridge. The harder the plug, the more attack, volume, trebles and distortion you get. I use plugs of different hardness to shape the sound coming from each string, the hardest plug is under the thick E string. Even six plugs of end wood spruce (effectively replacing the softer radial or tangential spruce that's in the top) will increase all of these parameters. With no change in weigh at all.

Compare with a firmly fixed string in both ends with a string with a spring in one end, or a drum skin that is tense or loose. Pretty logical to me.

I base this on my empirical experiments on many, many old parlor guitars. I always tried out my theories on one and the same guitar at first. To be sure, I have even made a test guitar where I can easily change plugs (and the hardness of the wood in the plug), saddle and the shim under the saddle to verify my findings.

So, what about string pins? They will do the same as the bridge, bridgeplate, plugs and saddle, only not as much. The material will change the filtering of the strings frequencies and the tone. The harder the material in the pin, the more attack, volume, treble and distortion you will get.

I guess one of us is right about this, I think I'm the one!

[wrench68]

Whether one likes or even is physically capable of perceiving the results of science is purely subjective. If one likes the sound, then by all means enjoy the music.

But facts and science are both absolute. I'm a mechanical engineer who analyzed machinery vibration for ten years, and then later in life applied it to acoustic guitars.

For the science of why guitars sound the way they do, my money is on Alan Carruth.

[AcousticDreams]

Originally Posted by RogerHaggstrom

I do one-piece segmented saddles with bone posts under each string and glued in soft wood replacing the voids between the bone posts. Spruce or cedar between the bone posts gives the guitar different tones, the cedar wood gives a "darker" tone compared with spruce. The very small difference in weigh of the segmented saddle can not explain that change in tone.

Also, the hardness of the bridge and the materials connected to the string matter. In my test guitar, I can replace a sliver of wood between the top and the underside of the saddle (the saddle ditch is actually an elongated hole through the bridge). Again, not a big change in weight. A spruce shim will dampen the volume and trebles, a really hard wood will do the opposite. The different hardness of rosewood and ebony is a major reason ebony bridges sounds a bit hard and sharp and rosewood a bit mellow in comparison (I like the sound of a rosewood bridge better).

I use spruce in my bridgeplate, not a hardwood. With spruce, I always get better dynamics and a better overall sound. I think the common maple bridge plate makes it hard to hear the sometimes subtle changes that come with different materials in the bridge and saddle.

When doing spruce bridge plates and the segmented saddle with spruce between bone posts (with a button of hard wood around the stringpin hole in the bridge plate to withstand the wear from the string's ball ends), I get a very mellow, beautiful and rich tone, but also low attack and volume. You can not be angry with the guitar with this setup, everything you do is nice sounding.

To counteract this not so pleasing behavior, I use harder wood plugs to connect the bridge plate hardwood button with the underside of the bridge. The harder the plug, the more attack, volume, trebles and distortion you get. I use plugs of different hardness to shape the sound coming from each string, the hardest plug is under the thick E string. Even six plugs of end wood spruce (effectively replacing the softer radial or tangential spruce that's in the top) will increase all of these parameters. With no change in weigh at all.

Compare with a firmly fixed string in both ends with a string with a spring in one end, or a drum skin that is tense or loose. Pretty logical to me.

Fascinating RogerHaggstrom! I applaud you on your experimentation and would love to Learn even more about your process.

While I do get the basics of what you are describing...if you have pictures Showing some of the process and parts I would truly enjoy that. I am truly interested. Pictures can sometimes offer a deeper clarification.

I especially enjoy your statement "I use plugs of different hardness to shape the sound coming from each string, the hardest plug is under the thick E string"

I also tailor each string with different bridge pins to shape the sound. Much like you, I use the hardest material( African Blackwood) for my Low E and A strings. Zirocote for my 3rd & 4th strings, & Unbleached oxbone for my 1st and 2nd strings. In some ways it is the same concept an electric guitar uses. As you are able to raise and or lower each side of the pickup to come closer to the string. Further I drill out the centers and add a specific size Brass and copper tube. Years of experimentation with different size tubes.

Several years ago, I use to split my saddle material with two different material. I no longer do this, as I overall prefer the harmonics rendered with unbleached bone for every string. I just balance my guitar with different bridge pins for each string...and also with a modified custom medium gauge set of strings.
Anyway...Looking forward to any pictures or further explanations you have on your process.

[Daddyo]

Originally Posted by cliff_the_stiff

Yes I do. I think the difference is subtle. I believe bone pins give me the best volume/ tone.
I find ebony pins to be pretty neutral and a good go-to particularly on bright guitars.
I don’t like plastic, and I have not tried the liquid metal pins because I don’t like how they look.

Adamantium?

[Herb Hunter]

Originally Posted by Knives&Guitars

Science is great. But so is personal observation.

Personal observation – anecdotal evidence – is no substitute for science. Personal observation has, at tlmes, had it that an aircraft approaching with its landing lights on in a twilight sky was an extraterrestrial space craft.

[talister106]

To elevate a bridge pin thread let me suggest Richlite bridge pins, debate.

[12barBill]

Originally Posted by talister106

To elevate a bridge pin thread let me suggest Richlite bridge pins, debate.

Richlite pins would produce a tonal spectrum very similar to ebony pins... sort of...

[Jim Comeaux]

Originally Posted by Wadcutter

Sorry Wade, I meant the pins that hold the strings in. Didn’t make myself too clear there.

Not to worry. You did it right the first time. The pins that hold the strings in the bridge are “bridge pins”. The pins that straps are hung from are referred to as an end pin, sometimes referred to as a strap button, in the lower bout and a strap button on the other end of the strap usually attached to the heel of the neck.

[RogerHaggstrom]

Originally Posted by Knives&Guitars

Fascinating RogerHaggstrom! I applaud you on your experimentation and would love to Learn even more about your process.

While I do get the basics of what you are describing...if you have pictures Showing some of the process and parts I would truly enjoy that. I am truly interested. Pictures can sometimes offer a deeper clarification.

I especially enjoy your statement "I use plugs of different hardness to shape the sound coming from each string, the hardest plug is under the thick E string"

I also tailor each string with different bridge pins to shape the sound. Much like you, I use the hardest material( African Blackwood) for my Low E and A strings. Zirocote for my 3rd & 4th strings, & Unbleached oxbone for my 1st and 2nd strings. In some ways it is the same concept an electric guitar uses. As you are able to raise and or lower each side of the pickup to come closer to the string. Further I drill out the centers and add a specific size Brass and copper tube. Years of experimentation with different size tubes.

Several years ago, I use to split my saddle material with two different material. I no longer do this, as I overall prefer the harmonics rendered with unbleached bone for every string. I just balance my guitar with different bridge pins for each string...and also with a modified custom medium gauge set of strings.
Anyway...Looking forward to any pictures or further explanations you have on your process.

I have actually never tried to work with string pins to tweak the sound. In old parlor guitars, ebony pins with 4 mm pearl dots is pretty much standard. And I don't think that string pins will make as huge difference as the bridge plate, plugs and saddle does, but who knows? Interesting to see that you came to the same conclusion with hard wood on the bass strings. I have found that a hard plug is especially effective on the thick E string, that string needs all the treble and volume I can give it. On a parlor guitar, I don't use any plugs on the unwound strings to dampen the dominating trebles from these strings.

Here are some slides, I have written an article about all my methods that will be published in the American Lutherie journal next issue or the one after that (according to the editor).

The segmented saddle with spruce between bone posts.






The plugs on an X-braced guitar with a spruce bridge plate.








The spruce bridge plate "cross" in a parlor guitar, no plugs needed for the unwound strings.






The hard buttons around the string pin holes.

[AcousticDreams]

Originally Posted by RogerHaggstrom

I have actually never tried to work with string pins to tweak the sound. In old parlor guitars, ebony pins with 4 mm pearl dots is pretty much standard. And I don't think that string pins will make as huge difference as the bridge plate, plugs and saddle does, but who knows? Interesting to see that you came to the same conclusion with hard wood on the bass strings. I have found that a hard plug is especially effective on the thick E string, that string needs all the treble and volume I can give it. On a parlor guitar, I don't use any plugs on the unwound strings to dampen the dominating trebles from these strings.

Here are some slides, I have written an article about all my methods that will be published in the American Lutherie journal next issue or the one after that (according to the editor).

The segmented saddle with spruce between bone posts.






The plugs on an X-braced guitar with a spruce bridge plate.





https://gammelgura.se/blogimages/202...1-07-03_59.jpg


The spruce bridge plate "cross" in a parlor guitar, no plugs needed for the unwound strings.






The hard buttons around the string pin holes.

Thanks so much for sharing these pictures. Without them I would not have completely understood just how the segmented saddle was put together. So very interesting and again...I totally applaud you on taking the time to do these bold experimentation's.

Unfortunately, I will have little to not time to do an experimentation for the next year or so, as I am about to embark on a recording journey. Something I have been meaning to do for a long time.

But afterwards...I will try out variations of your segmented saddle. I have been planning to do a laminate saddle for a long time now. Laminating Bone and brass.

And I have also long been wanting to do an experiment with greater mass Saddles. If you have not seen this new thread yet, Mike McLenison did a super interesting experiment.

https://www.acousticguitarforum.com/...d.php?t=626480

In this thread another person points out an article from Ervin Somogyi.
He talks about larger saddle mass and more string contact on saddle. He gives this example.

For what ever reason,... for my particular Style of playing, oddly the opposite works best for myself. What he considers the less efficient set up. I also do the same thing on my Nuts. I create a small surface for the sting to rest upon. It just meets my particular taste of tone.

[RogerHaggstrom]

I tried different woods between the bone posts, all the hard woods sounds pretty much the same, only the soft woods spruce and cedar sounded good. I don't think that brass will give the increased separation, dynamics and better "tone" I get from spruce/cedar. What you will get is a heavy saddle and a less metallic sound from the bone.