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Hey guys, Working on my first build, an LMI Custom Parlor.

I have my back on and just finished carving the braces on the top and am just getting ready to put the braces around the sound hole and put the bridge plate on.

The guitar is" Spruce top, Rosewood back and sides, ebony fretboard and bridge.

I am curious if anyone has used an ebony bridge plate and what the results were?

ebony split. Didn't like it for a plate but would use it for a veneer over maple.

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

To what end? Usually you try to keep mass down in the bridge area. Maple and rosewood will both do the same job with less weight. Some people use a spruce bridge plate with an ebony cap to catch the ball ends.

Thanks for the replies gent's, I have replaced a couple of 70's Martin bridge plates from rosewood to maple and from hearing them before and after they have a much brighter sound. I have also replaced a few bridges from Rosewood to Ebony and it does the same thing. I put an Ebony bridge on my little Gibson LG-0 with the X braces that that has quite a brilliant sound for all Mahogany.

So I got to thinking about an ebony bridge plate and wondered if it would make a difference in sound.

I know a lot of people say that ebony isn't a good tone wood because it is so dense but from my limited experience it seems to add a lot brilliance to the sound.

Just wondering if anyone tried it for a bridge plate.

Cheers,
Bob

Edit:


I guess what I actually meant was used for a bridge in relation to the mass of ebony

I did use it once as stated. The plate split.

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Thanks guys,

@John, Just out of curiosity, you had an ebony plate on a guitar and it split so I am assuming you swapped it out for Maple? Was there a distinct difference in sound between them?

I will go with the maple bridge plate that I originally intended on this one since it is my first so I don't want to make this one an experiment but was just curious.

Cheers,
Bob

You might consider orienting the grain of the bridge plate so that it is parallel to the soundboard's grain rather than across. That way the force doesn't act on a weakened area but the grain would reinforce the plate against the bending force of the string...

It makes sense when you think about it... the holes create a weak point.

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Typhoon Guitars
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ebony is more brittle and I didnt like the brashness. Maple sounded much better.

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

I have done a few, but to keep the weight down, I made them narrow (about 5/8"). They sounded fine, but I did not like the risk involved in using a plate that small.
If you want a bit more sustain and brilliance, I recommend a black locust bridgeplate. It is not much heavier than hard maple, but it is stiffer and harder.

_________________
John

Ebony is dense, but that's not all there is to it. It also has high damping properties. Think of lead compared to brass; lead is denser, but it' s never used for making bells....!

If you want dense, and keep damping low, try African Blackwood or Cocobolo(both of which are true rosewoods, BTW). Both are denser than ebony, yet have some of the lowest damping of all woods.

@ Grunpy, Thanks for that explanation, that is probably the best example I have heard about using Ebony.

I wasn't aware that Cocobolo was more dense than Ebony, I have been under the impression that it was a good replacement for Brazilian Rosewood. I have used it on a couple of guitars to replace cracked rosewood bridges. I (or my clients) didn't notice a big difference in the sound but the color and grain was almost a dead match to the old ones.

Thanks again
Bob

What exactly does dampening mean? I dropped the african blackwood bridge blank and compared it to ebony, and while there is a difference it's not really night and day. It really took some careful listening to tell them apart but I can tell that african blackwood has a sharper crack when dropped compared to ebony.

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

I agree with grumpy... African/Gabon ebony dampens vibrations, and in my experience just sucks high frequencies right out of the tone. This is not necessarily a bad thing... it can really mellow out a uber-bright guitar or one with harsh, shrill trebles.

And John is spot on too: it is very brittle/splitty which is a great reason to avoid it as a bridge plate.

I would add that Macassar ebony and Malasian blackwood are two notable exceptions... they are true ebonies that both ring like a bell, are dense, and are much less likely to split, though they are more brittle than maple and Indian rosewood.

@James Ringelspaugh, I am not sure I agree with that. I have replaced a few bridges on guitars from Rosewood to Ebony and it has been my experience that Ebony dampens the low end and seems to bring out the mids and high end. They also don't seem to have the sustain that Rosewood had. I have replaced bridges on 3 different Martin D18s and each one seemed to have a brighter and a bit more harsh mid tone to them(normally D-18s tend to be bass heavy so that is why I have had requests to swap out the bridges. One of them was a referral from the first one I did and the third was my own.


I currently have a block of Gabon ebony I have made a couple of them out of and I didn't notice that it took away from the highs and mid frequencies, although one is on my Gibson LG-0 that I rebuilt with X-bracing and I didn't hear it before I got it (the back was split at the seam and half falling off) plus it had the crappy black plastic bridge so anything would have been an improvement.

@Tai Fu, I doubt you would hear a lot of difference in a piece of wood as small as a bridge when dropping it. My guess is if it was a larger piece you would hear some difference if taping it with your finger. Over the last few years I have been taping almost every piece of wood I find. I find it pretty amazing that to nearly identical pieces of wood can sound so different.

Technically, damping refers to the rate of energy dissipation in the material. One measure of it is the 'Q value', which is the proportion of energy dissipated for each full cycle of vibration. Thus a Q value of 50 means that 1/50th of the remaining energy is gone per cycle. You can see that this works like compound interest, or fret spacing. Frets spaced such that each one is 1/17.81715 of the remaining distance to the saddle, and 12 frets give you half the string length. If you had a piece of material that had a Q value of 17.81715, then half the energy would be gone in 12 cycles, and so on.

The Q values of woods vary a lot, and depend as well whether you're talking about vibration along the grain or across it. You might see a Q value of around 60 along the grain for a piece of softwood with high damping, and some redwood and Brazilian rosewood will run closer to 150 or even a bit higher. Note that there's no necessary relationship between Q value and density: balsa can have about as high a Q value as spruce, and Spanish cypress has about as high a Q value as the rosewoods.

Obviously, materials with high Q values tend to 'ring' longer. A low Q value will also tend to kill high frequencies faster than lows: 100 cycles at 100 Hz takes one second, while at 1000 Hz it takes 1/10 second, so if the energy drops by half in 100 cycles, you'll lose the highs first. Q value also tells you how hard it is to get the thing going off resonance: eardrums have very low Q and a more or less 'flat' frequency response: it's about as easy to move them at one frequency as another. Something like a bar of aluminum, with a Q around 1000, will be very hard to drive off resonance, and gives a musical tone when struck. The quartz crystals in watches have Q values in the millions, which is why they only go at one frequency, and make good time bases.

This doesn't always work the way you think it might on guitars. Western red cedar tends to have very high Q compared with spruce, which should give it better high frequency response. However, cedar topped guitars are generally known for having a 'warm' or 'dark' sound. Maple, with a much higher damping factor than rosewood, tends to make 'brighter' sounding guitars. We tend to equate 'bright' with a lot of highs, and 'dark' or 'warm' with more lows, but here we may see the reverse. I'm not sure what gives here, but it's probably more complicated than it 'ought' to be.