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whats everyone's favorite wood for bridge plates? thicknesses?

is there a major difference in tone using rosewood or say maple?

is there any other kinds of woods widely accepted?

i have so many questions about one little piece of wood that nody will see haha. also i went searching and no specific topic or much discussion that i could find on them so i figured id start it off.

A common mis conception is that Rosewood will give more bass. I believe this is because of the huge rosewood bridgeplates used by Martin for a few years. Maple is actually a little warmer sounding that most Rosewoods. My preferences are for Maple for a vintage tone, and Honduran Rosewood for a more modern tone. I normally thickness them around .090". I've used Adirondack Spruce( a little bit thicker) for a bridgeplate on a couple with a "platemate" where the strings seat, and a 1/4" brace directly behind the bridgeplate.

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Paul, I was thinking of posing this question too. I'd like to know what the effects are of larger vs. smaller and heavier vs. lighter bridge plates on tone and volume...?

I always think of the bridge plate as simply the 'inside part' of the bridge. The effects on tone and volume and what have you from making it heavier or lighter or whatever are pretty much the same as those of making the bridge itself heavier or lighter. In many cases it ends up, IMO, being a matter of folks hearing what they expect to hear. If you think maple plates are 'warmer' sounding than rosewood, then you'll probably hear that. I found it interesting that, when I had people try my 'matched pair' guitars at an ASIA meeting, without telling them what the difference was, many asked if it was the bridge plate material. It wasn't; one had 'standard' bracing and the other 'double-X'.

For me the biggest 'job' of the bridge plate is to keep the string balls from tearing up the top. It needs to be hard, tight grained, and tough. lt also helps if it's not too prone to splitting, since it's a drag to replace a split bridge plate. In light of that, I'd avoid flat cut _anything_, but especially Brazilian rosewood, which is quite prone to splitting. Skew cut hard maple is good, but I prefer skew cut persimmon. It's not as easy to get, though.

I've wondered about the bridge plate as well... but more in the context of using a truly pinless bridge (not even the little "Doolin pins" ). It seems that it becomes unnecessary (in terms of the string ends messing up the top) and could be replaced by a lighter and stiffer lattice bracing.

So would the effect of such a construction (pinless bridge + lattice) on tone be basically the same as a traditional construction (bridge + bridge plate) of equal weight?

Christian

But isn't the plate adding to the stiffness of the top at that area and by being coupled to the X braces acting as a gusset and when the bridge is glued on even more stiffing that area. After all the bridge is a brace and a very inportant one as it's the first point that the string energy is distributed to the top face and braces. I would also think that having the hardwood plate also helps to keep the soft wood top from deforming from the torque of the bridge. You can get away with it on a classical I would think being the torque is less then a steel string. I could be wrong though. Just some thoughts I'm having about it. I might think that the position of the plate and bridge from the X and the mass and density and dampening quality of wood might have a bigger influence on the tone. An the X angle and it's distance from the sound hole. But I could have the wrong logic here.

Chris, I'm only thinking out loud with that idea...

...but the idea seems like an application of the cube rule. You replace the 0.08"-0.1" thick hardwood bridge plate with a spruce lattice. If the braces of the lattice are only 0.25" high, you'd have a substantially stiffer, but also lighter structure below the bridge to resist the torque. You could also couple the lattice to the x-brace.

Again, I'm just thinking out loud, and I may very well be missing the obvious.
Christian

its a matter of tone aswell.

when i went to NI i asked mr lowden or mr Mcillroy (cant remember, both use pinless bridges though) about using a softwood bridge plate (i realise that it isn't the same as a lattice, but it is halfway there) and the reply was that they had tried that and it gave a different tone and they preferred the tone of the hard wood bridge plate.

however lowden has quite alot of bracing in that area and mcillroy has a humongous amount of bracing in that area, so UMMV

plus adding all that extra stiffness right where the bridge goes - is it really needed? and imagine making a lattice caul to glue the bridge on! suppose you would have to vacuum it?


it is something to think about though, with a bit of thought and trail and error, it could help, i just wonder whether putting alot of stiffness in such a small area would have the desired effect? after all, there is a big fat x brace there....

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I'm also just thinking out loud Christian. It's reading that dang Responsive Guitar that has me thinking about a whole lot of things I never thought about before.
You know that Mario Proulx has a little brace that he adds I believe behind the bridge plate that he claims improves the tone sometimes. I think it might be a balancing act for sure. I'm just wondering about the deforming effect. Well if you try it be sure to report back.
Maybe we'll get some more thoughts and info on it.
I'm also not to clear on what the lattice would look like.
What do you think the effects of the less mass might have on the tone?
If you get too stiff there you could sort of lock up the top and screw up the mono pole. That might give you less volume and less bass responce as the top can't move up and down as freely.

Chris, I'm really tempted to try. It's just my personality I guess - I finished only one steel-string guitar so far, am still struggling with lots of stuff, but somehow I just want to experiment
If I go for it, I'll definitely report back!!! If it turns out less than good, I'll learn how to replace a top...



I sure hope so too...I asked that question before and got very few answers...probably most builders have never tried it (for good reason?)



Me neither It would really be starting from scratch for me. I have a hunch that I'd make the braces 1/8" wide, maybe start with 3/8" height and have them 1"-1 1/4" apart. Based on absolutely no experience whatsoever



You know, I could reiterate what other builders say about less mass in the bridge area (more bass response?), but again...it's not my own experience I would base that on.

After I got the idea, I did some research and found that Michael Greenfield had done something like that. In an interview about a guitar for sale at http://www.12fret.com, he states:
"I went to a pinless bridge so that I didn’t have to design my strutting pattern around a traditional bridge plate with six holes drilled through it. It allows me to do anything I want underneath the top, for instance my lattice bracing pattern that this G2 utilizes."

So it seems that I'm not completely mad with regards to this idea. You can admire the guitar here: http://www.12fret.com/new/Greenfield_Michael_G2_Jun9pg.html and listen to a sound clip of David Martin playing this guitar here: http://www.12fret.com/new/SoundFiles/Greenfield_Michael_G2_Jun9.mp3

Of course it's impossible to tell, which aspect of the sound is due to the bracing and pinless bridge, but I really love the tone. Maybe I'll just contact Michael Greenfield and see what he is willing to share



Yes, I guess that's the case with any bracing...if you overbuild, you lose volume and tone. I'm optimistic about the lattice though, as it is really stiff on one hand, but allows the bridge to move nonetheless. This is really nicely illustrated in this video about John Williams picking up a Smallman (around 3:30 in the video)

http://www.youtube.com/watch?v=tCtalGJcP8A

best, Christian

Sounds like a good idea to contact him and see what he has to say. You might also ask him about the bracing in the G2 while your at it.

Weight is the enemy of tone. I use flat cut maple. I also always make my bridges concave along their length. A bit less than 1/16" in 6" length. This helps keep the corners of the bridge from pulling away from the top when the top invariably takes a little belly. I also make the bottoms of classical bridges concave,but use a spruce plate beneath them. I glue them down with a pre fitted curved caul that I fit before the back is put onto the guitar. On classicals,the caul has to be grooved to fit over the fan braces. You need to be sure to get 100% glue contact when gluing the concave bridge down.

As an illustration of how critical weight is,I was asked to make a Gibson Mastertone banjo sound better. The owner was convinced that his was no good. It had a rosewood bridge on it that was the same dimensions as a regular maple bridge. I could have taken the banjo home,and charged the guy some money for adjusting his banjo. All I did was sit there and put the maple bridge back on. It came to life at once. Several guys had me work on that same model banjo. Mostly they just needed the skin tighter. By the way,those 3 footed banjo bridges are also bad for tone. Cut away that middle leg,and it will sound considerably better. Then,sand the bridge down as thin as it can stand the string tension. That helps a lot. Do not use those banjo bridges with thick ebony tops. They look cool,but also hurt tone.

Now,of course,guitar bridges must be made of substantial wood so they don't self destruct. I use Brazilian rosewood,flat cut for strength. I never use ebony. It is too heavy,and it is brittle. I had a Martin bridge's saddle crack right over while stringing one. It was one of their models that always had a high saddle (D-35?). Can't recall. It took the front of the bridge right off. It really wasn't my fault,but of course I had to replace the bridge for free.

Don't you sand your bridge to match your top radius?

Yes,I failed to say that,but I add a little more curve to the bridge because the top will curve under tension.

hello everyone just thought id ask two questions since ye'r on the subject

Does anyone have a preference to which way the grain runs on flatsawn wood
should it be rainbow'ed ?(sorry) so it would comform with the shape of the top ?


Would it be suitable to make plates from an old fretboard
is the grain tight enough ?

hope you get what i mean when i say rainbowed but it was the only thing
i could think of because its never upside down
thanks again for the advice ..tomas

i was thinking of just cutting up a bridge blank into a few plates. has anyone ever used walnut? its really dense and is not prone to cracking or much change with humidity. i have cutoffs from the neck block on my first. i thought it would be interesting to maybe even use cutoffs from my first koa back, or the bubinga or cherry from #2 and 3 that im working on now. but would this stuff be good enough? seems like they would be dense enough... maybe not the koa. just looking for ways to save time and money.

Did you read my post? Don't weigh your top down with un- needed extra weight. Walnut would be o.k.,Koa,no. Bubinga- too heavy. Do not worry about saving nearly NO money when a bad choice wil hurt your tone.

I'm going to be trying elm for my bridge plates as it won't split very easy as rosewood does.I thought about useing walnut, but it might split under tension.I have been useing maple and like it as well.Elm is one of the hardest woods to split for firewood, so i think it might work well.As for tone, we'll just have to see.

My question on Elm would be, why is it hard to split? Some woods might be hard to split because they are "punky" or "springy", not because they are hard. In that case, I'd think they would have high damping properties, which wouldn't seem to be good for a bridge plate.

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I disagree that extra weight is always to be avoided in the bridge area. Depends on a lot of things. I've removed light bridges from guitars to replace them with heavier ones and seen a vast improvement in tone.

But no need to argue. Try it on some guitars. Stick 5 or 10 or even 20 grams of washers, nuts, whatever you can find on a bridge with some putty or double stick tape and see what happens. In my experience, it will help some guitars and hurt others.

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i completely agree with not compromising the guitar guitar over saving a few bucks. I don't think any of us here are trying to do that. Guess i should have mentioned that.
just trying to figure out what i can use and not waste.

Elm should not be appreciably heavier. However,what makes elm stronger is that it grows in spirals that reverse every so many years. We use it on wagon wheel hubs in Williamsburg for that reason. BUT as thin as your bridge plate is going to be,you may very well NOT have the benefits of the grain reversing. Maybe if you cut it just right you could get grain reversal,but the growth rings are also curved,while the bridge plate is flat. So,you may not get the grain reversal in that thin a piece.

Chasson,you do it your own way,and I'll do it mine. Your contention that weight doesn't matter is counter to common sense.

Hare is my reasoning,and it is borne out as far as I am concerned by the radical change upon tone between light vs heavy bridges in banjos. If you read my earlier posts,I told how I changed a rosewood bridge on a banjo back to the usual maple one,and completely opened the tone back up. Lightening the banjo bridge further enhances the tone,as it does on violins,which I also make for professional players.

The string has only a certain amount of energy when it vibrates,to impart a movement in the bridge. It is elementary physics that the grater the mass of a body is,even in outer space,the greater the moment of inertia is to set it in motion. Add to this the more delicate the harmonics of the string are,the greater the importance of moving the bridge is with that small amount of energy.

One of the worst flat top guitars ever made was the Gretsch rancher. It had a very large bridge,and added to it was a metal string bar from their trapeze tailpiece from their arch top models.

It makes sense that a lighter bridge will allow greater vibration to be incited.This includes the bridge plate under the bridge.

You cannot always judge what is really best from using factory made instruments as examples. Use of large,heavy bridge plates makes the top less able to assume a dome under the bridge,causing it to come loose and causing warranty work for the company.

One of the best sounding guitars ever made was the Gibson advanced jumbo. It had a small bridge. Indeed,all of their early jumbos had small bridges. Some of these early advanced jumbos have incredible tone. They were not built like Martins with bigger,heavier bridges and massive bridge plates. Things have changed over the years,and not always for the best. Larger,heavier bridges have replaced the earlier,lighter ones. Even acoustic bridges with metal adjustable bridge saddles have been incorporated into more recent designs. A lot of this shift is to make less warranty work for the factorys. Some are to add "features" for the ignorant.

These earlier Gibsons seem to be exceptions to the rule that most factory guitars are actually over built for the sake of durability in the hands of players who may range from professionals who know how to care for their guitars,to rank amateurs.

Right now I believe that the top and the bridge must be in a certain equilibrium (or at least within a range) to make for a good guitar. A very light bridge coupled to a very heavy stiff top seems to be unable to move the thing properly. It should sound thin and weak, or at least that is what I feel it could happen.
While a too heavy bridge...well that is easiest to check, attach a 10 to 20 grams bolt to a bridge and you will see. It definitly cuts down on the responsiveness.
Perhaps the tension of the strings should be matched prportionaly too, and the player attack as well.

This thinking seems to match to what gathers up in the real life:

stiff Adi top top, ebony bridge, heavier strings, flat picking and strumming.
lighter top, rosewood bridge, low/medium strings, fingerpicking etc. etc.

In the nylon group, flamenco guitars have the tops slightly thinner and seem under-braced compared to their classical counterparts, but the bridges are considerably lighter too... They sound very different of course, but they work.

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I totally agree that using factory instruments as a guide isn't relevant. I'm talking about lightly built, responsive guitars. I agree with your quote above to a point. But one can go too far in that direction. Yes you have a limited amount of energy but if all that string energy gets released too quickly, you can end up with a guitar that lacks focus and is jangly. And light bridge patches with light bridges can lead to drastically increased string noise too.

I'm absolutely not saying that heavy bridges are always good. I'm just saying that on lightly built guitars, it's possible to go too light.

Not trying to start an argument. It's just that I've very intentionally experimented with this several times (with the aid of a second set of experienced ears) and I've had different results than you.

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