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I made my first one this week. I love the looks, but it is just so heavy. I made a rosewood bridge at the same time, and while I did not put them on the scale, it is noticeably heavier.
The customer really wants ebony, but I feel it will rob tone.
Does anyone do anything to lighten up their bridges like making a few holes on the bottom?
Am I worried about something that will be just a minor difference?

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"An adventure is only an inconvenience rightly considered. An inconvenience is an adventure wrongly considered." G. K. Chesterton.

This issue is something I worried over quite a bit when I first began building 10-string classicals. Obviously a 10-string needs a larger bridge than a 6-string, and I was concerned about mass and the effect it would have on the top. When I attended last year's 10-string festival, I had the opportunity to inspect and take measurements of a number of fine guitars. One of the things I was most surprised about was that the loudest 10-string there -- a new Bernabe -- also had the largest bridge.

That seemed counter-intuitive to me. Then I got to thinking about the way the top works. Folks like Alan Caruth have forgotten more than I know regarding top behavior, but it occured to me that the bridge sits at a node (for the strings, at least), and that if this is also a node for the top, then the top is not vibrating at that point. Thus the mass of the bridge might not play as important a role -- or so I began to think.

I have built guitars -- both 6-strings and 10-strings -- using padauk, EIR, and cocobolo for bridges. The coco was the heaviest (density of about 1.1g/cc) and the paduak the lightest (density about 0.7 g/cc). But the guitar (a 6-string) I built using coco for the bridge, is also one of my loudest. Go figure.

Personally, I believe the acoustic conductance properties of a bridge are more important than its mass -- within reason, of course. In that respect, I don't think ebony is one of the best materials to use. You almost never see classicals with ebony bridges, and I believe that is why. Steel string builders can get away with ebony, I'm thinking, because it might result in a warmer sound. But this is largely conjecture on my part.

Best,

Michael

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Live to Play, Play to Live

Hi Steve,
I just bought a little digital scale (up to 500 grams) from Harbor Freight. I will weigh every bridge from here on out. I think Sylvan gave an idea about comparison months ago. For example, my eirw bridge is about 25 grams, ebony about 30 grams. I may take my cocobolo bridge off and replace it with braz RW, for the same reasons you're concerned about. You can also ebonize a rosewood if you can swing it with the customer.

Run your ebony bridge to the post office and have them weigh it. Weight is important, especially in the bridge area.

Michael,
Thank you for that response. For this koa guitar, I am a little concerned just because koa is not the greatest top wood, and now adding a heavy bridge to it. Perhaps as you say, weight on the bridge won't make that much of a difference.   I know some people like adding brass bridge pins, that certainly adds weight. This being my sixth guitar, I don't know so much more than I know about making guitars.


Terry,
I have scale, although I did not measure the bridge yet. It is noticeably heavier than the rosewood one.

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"An adventure is only an inconvenience rightly considered. An inconvenience is an adventure wrongly considered." G. K. Chesterton.

Ouch, Steve. You're correct, I think. With a koa top, ebony is not the best choice for a bridge, unless, I suppose, its owner only does heavy strumming.

The problem we face is that, because of factory hype, people think that ebony bridges are more "premium." I used to think that myself. But the truth is, according to people more knowledgeable than I, ebony tends to damp vibration. It's apparently not just weight causing this, but the nature of the wood itself.

You made that ebony look mighty pretty, though, so if that's what your customer has his heart set on, use it. No doubt you'll still make a fine-sounding guitar.

[QUOTE=CarltonM] But the truth is, according to people more knowledgeable than I, ebony tends to damp vibration. It's apparently not just weight causing this, but the nature of the wood itself.

[/QUOTE]

This old chestnut comes up time and again. I strongly recommend reading the wise words of Alan Carruth here.

Not so much "damping" as "impedance" in his view. And imho as in all things guitar wise "it all depends" - some guitar designs will work best with an ebony bridge.

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

[QUOTE=Dave White]Not so much "damping" as "impedance" in his view.[/QUOTE]
Some of my understanding of the nature of ebony is based on what Alan wrote. You're right, "impedance" might be a better word in this case. It's the reason, I suppose, that when you tap an ebony bridge you tend to get a "tink" sound, rather than the "tinggg" of rosewood. It wants to reflect vibration rather than transmit it. Good for fingerboards, though.

What d'ya think--closer?

[QUOTE=CarltonM] [QUOTE=Dave White]Not so much "damping" as "impedance" in his view.[/QUOTE]
Some of my understanding of the nature of ebony is based on what Alan wrote. You're right, "impedance" might be a better word in this case. It's the reason, I suppose, that when you tap an ebony bridge you tend to get a "tink" sound, rather than the "tinggg" of rosewood. It wants to reflect vibration rather than transmit it. Good for fingerboards, though.

What d'ya think--closer? [/QUOTE]

Calton,

I think what you said in your original post was just fine. It's just that the word "damping" has this negative connotation with people sometimes and I just wanted to remind people that "it all depends".

I make my tops with pretty big curvatures and know that too light a bridge (eg Brazilian r/w) just doesn't seem to work at all for me. I think Al gave me a glimmer of why in that post - arching makes the top stiffer and raises the pitch, and a heavier bridge brings the pitch down more than a lighter one.

This probably doesn't help Steve with his dilemmna though .

Steve,

Why not a compromise and use Macassar ebony? This is more at the "rosewood" end of the spectrum but has a lot of the looks of ebony. This has made great bridges for me.

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

Here's what I did on my latest:

1) Zootman had some very dark colored BRW...it looks like light colored ebony.
2) I thinned it to .330" at center
3) I flattened out the back side...no belly
4) I rounded over the back side significantly to give it a more streamlined appearance.

Bottom line...all the little things reduced mass ...it's 24 grams and it looks like ebony. I suppose if I had applied black FB dye it would appear to actually be ebony.

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JJ
Napa, CA
http://www.DonohueGuitars.com

[QUOTE=Dave White]........

Steve,

Why not a compromise and use Macassar ebony? ........[/QUOTE] Dave, I just realized I forgot to make this bridge a lefty, so I'll talk to the customer about using Macassar ebony. Thanks for the suggestion.

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"An adventure is only an inconvenience rightly considered. An inconvenience is an adventure wrongly considered." G. K. Chesterton.

If the Koa top is thinned and braced to its optimum then the Ebony will be fine.
it may even help with sustain!
Mike CollinsMike Collins38965.7745138889

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Mike Collins

I have a piece of Macassar E. and the stuff has a beautiful ring to it, exactly what I was thinking of using next.

Greg

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Gwaltney Guitars

Michael,
I'm sure you are right.
This is my 6th guitar. I'm not up to optimum yet.
I have the top at a tad bellow .105" and the braces are carved to the best or my ability. It has what I think is a nice tap tone now. I'm not sure how to optimize it beyond that.

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"An adventure is only an inconvenience rightly considered. An inconvenience is an adventure wrongly considered." G. K. Chesterton.

I recently made a pyramid bridge from african blackwood, rings like rosewood and looks a lot like ebony. Weighs 28g.

PaulB38965.9963657407

Another option might be Katalox (Swartzia cubensis.) Some is reddish purple, but some is very very dark charcoal-purple; darker yet when oiled. It is fine grained, very hard, and wear resistant, with a bright resounding *ping* when struck (like BRW.) You can find pieces that are very uniformly colored. Just a thought.

Dennis

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Dennis Leahy
Duluth, MN, USA
7th Sense Multimedia

nice, Paul.

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Howard Klepper
http://www.klepperguitars.com

When all else fails, clean the shop.

I agree with Dave and Mike here, i have a stealthy ebony bridge on my walnut OM-H guitar and it doesn't damp the sound whatsoever, i think that we should never focus solely on the bridge thickness itself, Like Steve said, the ebony bridge felt heavier in his hand than the rosewood one, if that's what the customer wants, that's what he should have and the whole bracing system and top plates should be treated in function of that IMHO.

I think the weight of the bridge can play a big role in what sound your looking for. If your looking for sustain a heavier bridge can help you get that assuming you have enough energy to set it into motion. A light bridge can help with quick attack and such.
Now don't ask me what an ideal bridge should weigh because it just depends near as I can tell.

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Jim Watts
http://jameswattsguitars.com

[QUOTE=Howard Klepper] nice, Paul.[/QUOTE]

Thanks Howard.

Frank Ford has to get a lot of the credit tho, he's got a pretty good demonstration on how to make them over at frets.com.

Very cool bridge Paul !

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CRAIG LAWRENCE of AUSTRALIA
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