Bridge and bridge plate wood

[peter.coombe]

A question for the experienced guitar builders.

I notice that Rock Maple and Rosewood seem to be the most popular bridge plate woods. These are at opposite ends of the spectrum as far as sound goes - i.e. Maple is high damping, Rosewood is low damping. So, does the bridge plate wood make any difference to the sound? Any reason why not to use Ausse hardwoods such as Blackwood, Tassie Oak etc?

Also, how much influence on the sound does the bridge wood make in the guitar? I have noticed there is a great deal more variety of woods used for bridges in guitars than mandolins. The mandolin world uses Ebony almost exclusively and for good reason. I played around with various woods for bridges a few years ago, but Ebony has a unique sound that I much preferred. The only wood that showed any promise was Tassie Blackwood, but it was way too bright for my taste. However, I have used a Blackwood mandolin saddle with success to correct a mandolin that was unbalanced, bassy and lacking in treble. There are a few followers of Red Henry who advocates Maple bridges, but I strongly disagree with him. His argument was that mandolins are similar to violins which use Maple bridges, so a Maple bridge should work on a mandolin. My Bridge supplier made a Maple bridge for me on their CNC machine so it was identical to the Ebony bridges. It sounded louder, but somewhat harsh. I also made some Maple bridges with the same result.

Also, does the size of a guitar bridge matter much, i.e. does a heavy thicker bridge sound much different from a thinner bridge? The bridges I use on my mandolins come supplied weighing around 14gms. If I take some wood off and get the weight around 10-11 gms it makes quite a difference to the sound (improved), but if you go lower than 10gms then the sound becomes thinner and brighter. So at least on mandolins the weight of the bridge is very important. Interestingly if you just drill a couple of holes 10mm apart in the saddle then the sound improves. Why that is I have no idea. Can't be reduction in weight because it only makes 0.1 gm difference which is insignificant.

[Bob Connor]

Ebony damps high frequencies so I can see why it would be suitable for a mandolin. Classical builders rarely use Ebony as it's difficult enough to coax top end out of a classical. Greg Smallman uses Padauk

I've noticed a difference when I use Rosewood for bridges and bridgeplates.The highs have an extra zing in them that I really like so I'll use Brazilian Rosewood for bridges wherever I can.

I just got in 50 Honduran Rosewood bridge plates last week so that'll keep me going for a while.

The Hawaiian lap steel I've just built has a Rock Maple bridge plate and a Blackwood bridge and it sounds fine. But I didn't want the zingy high end sound for a slide guitar so I chose the woods to achieve that .

Just delivered a King Billy topped OM to Tassie that had a Blackwood bridge and it too sounded good (I did use a Honduras Rosewood bridge plate in that one)

The only thing I have against using Blackwood is that it's a bit light. I like the bridge to be bout 28 grams on a steel string and a blackwood one will generally come in at around 18-22 grams depending on the piece. Idid get a few pieces of Blackwood from Queensland a while back that was quite heavy and really dense - absolutely perfect for bridges.

So I guess you change things around to suit Peter. Just a little more difficult swapping out a bridge on a guitar as opposed to a mandolin.

[peter.coombe]

Thanks Bob. There is some useful info there.

Nobody else?

[ozziebluesman]

G'day Peter,

I have used Tasmanian Blackwood as a bridge plate material on four acoustic guitars and one with maple from Stew Mac as an experiment. I am happy with volume levels and have noted a warmth to the tone on all my guitars I have built. As a player I really like a big, full, warm tone from an acoustic guitar so I am striving to achieve this with all my builds. The maple bridge plated guitar had more volume though. This could have been due to changes to xbrace opening angles and bracing styles. The Blackwood bridge plate material was fine grained pieces and they where all around 2.5 mm thick. The Tasmanian Blackwood used was offcuts from my first weissenborn set supplied by Tim at Australian Tonewoods. The wood was a beautiful rich red colour, very stiff and tight grained. It was quite heavy too!

I have built three weissenborn style guitars and through my research it was traditional to use the same material as the body of the guitar for a bridge plate material. Two of my weiss guitars where all blackwood and one was Tasmanian Sassafrass where I used a piece of sassafrass for the bridge plate. This guitar had much more volume than the two blackwood guitars but the blackwood guitars had a more traditional tone. I put the extra volume down to the fact the sassafrass was half the weight of the blackwood. I feel Sassafrass makes a very good sounding instrument.

Interesting post Peter.

Cheers

Alan

[Allen]

For bridge plates I've used a lot of Qld. Walnut. It's tough and makes a good "ping" when you drop it on the tiles. I've got a lot of it left from building a couple guitars. It's way too much work to build instruments with. Just destroys edge tools so the rest is bridge plates. Also use Indian Rosewood, Honduran Rosewood, and Spruce in ukes with tie bridges.

For bridges I've used Indian Rosewood, Ebony, Minneretchi, Pink Ivory and even Lace Sheoak. The choice between them for the most part has come down to aesthetics. Colors of trim to compliment body and top.

[graham mcdonald]

I think you have to remember that the bridge and bridgeplate are effectively a big cross-grain brace on the soundboard, which will be adding stiffness in that part of the soundboard and effecting how the soundboard is resonating. That is part of the thinking behind Smallman's short and lightweight classical guitar bridges as well, perhaps, why scalloped X bracing helps the sound of steel string guitars as the scalloping offsets some of the stiffness added by the bridge.

I will disagree a little about the Red Henry style bridges. On some mandolins they work really well, on some they will make a bright mandolin entirely too harsh. I think they really came out of Red's desire to add some zing to the sound of tubby old Gibson A models. As they only take half an hour or so to make it can be an interesting exercise to swap bridges around and hear how the sound changes.

cheers

[peter.coombe]

Graham

I have made Red Heny style mandolin bridges and they certainly do change the sound very much for the better, so he is certainly on to something. I think he has changed his opinions about Ebony as a bridge material more recently, but he still mostly uses Maple. The earlier Ebony bridges he made were much too heavy, my Henry style Ebony bridge was more than 30% lighter whcih would explain why he was so negative about Ebony. When Red started his experiments they were alll done on a Randy Wood F5, the tubby oval hole Gibson sound never was part of it. The modifications I make to the Brekke bridge are based on Red Henry's work, but the Brekke is adjustable whereas Red's one piece bridges are not.

Peter

[woodrat]

Hi Peter, I like to use either Rosewood or Wenge for bridge plates. I like to hear that really glassy sound that indicates that it is a really good transmitter of vibrations. I had some Amazon Rosewood (D. Spruciana) from Gilets that was so glassy when you tapped it with the back of your fingernails and used it in several successful guitars. So that is my criteria...it has to be what E Somogyi calls vitreous in his book. Having a nice glassy tap. Just what I look for in a bridge plate. My personal feeling is that the bridge plate is one of the most important bits of timber in the whole guitar.
As for bridges I have used ebony on many of my guitars simply because that matches my fingerboards. On my recent Lutz/Mahogany OM I used rosewood instead of ebony even though it has an ebony fingerboard. That guitar sounded amazing. I remember Darrell at Gilets in Sydney once said to me that he would always use rosewood even if it meant staining black to match an ebony fingerboard because it is sonically superior. I think that there is a lot of merit in that statement after that recent experience. Also classical builders use rosewood for bridges but seldom ebony. That too leads me to think that RW is the best choice.

John

[bunker]

Hello Peter, one and all,
I only have 5 under my belt and have used maple, jarrah and sheoak for bridge plates with jarrah and mulga so far for the bridges. The mulga comes up trumps being very glassy in sound, gives a great finish and comes out around the 28- 30 gm mark. Of recent times I have noticed a few builds where the plate is made from the same wood as the top with differing grain orientation and then has a small reinforcing strip of hard wood fitted to take the peg holes and string ball ends. I can see the merit here in weight while still having something solid that the ball ends won't dig into. I am just in the throws of getting a design together for my next one and was thinking of going down this path so I guess this is a good post to throw this in and see what you think. I will be using mulga for the bridge again though.
Archie.

[woodrat]

Hi Archie, Yes I have done this too...I found the idea on Bruce Petros' website so I thought that I would give that a try. It works too. Perhaps a good idea if the bridge material is a bit on the heavy side as it makes the whole arrangement lighter.

John.

[bunker]

Hi John
Thanks for the reply. Your comment is along the lines of my thinking in so much as keeping the mass down but the strength there in this important area. I think I shall give it a go.
Archie.

[Philstix]

Interesting topic. This reply does not come out of a lot of building experience, I've only built a few, but out of a lot of repair work. I assume we are talking about steelstring bridges as they transmit vibrations a little differently than classical bridges and very differently than mandolin bridges. String energy levels are also very different. That said, I would rank the effect of which type of wood used relatively low as a predictor of sound. In rough order, saddle material, saddle height, bridgeplate stiffness, bridgeplate size and shape, bridge size and shape, overall stiffness of top, weight of bridge and plate, and finally types of wood used. Highs take a lot of energy. Harder saddle, higher saddle, stiffer bridge and plate, smaller bridge and plate, lighter bridge and plate, stiffer wood will all emphasize highs. Use what looks good and wears well. IMHO

[woodrat]

Interesting topic. This reply does not come out of a lot of building experience, I've only built a few, but out of a lot of repair work. I assume we are talking about steelstring bridges as they transmit vibrations a little differently than classical bridges and very differently than mandolin bridges. String energy levels are also very different. That said, I would rank the effect of which type of wood used relatively low as a predictor of sound. In rough order, saddle material, saddle height, bridgeplate stiffness, bridgeplate size and shape, bridge size and shape, overall stiffness of top, weight of bridge and plate, and finally types of wood used. Highs take a lot of energy. Harder saddle, higher saddle, stiffer bridge and plate, smaller bridge and plate, lighter bridge and plate, stiffer wood will all emphasize highs. Use what looks good and wears well. IMHO

Philstix, You make a lot of good points here. There are really so many variables to consider. When I said that Rosewood seems to be the best choice it is not written in stone for me. There are bits of Rosewood that I would reject because they dont have enough "glassyness" when I tap them. I really like to hear it ping. I have also used some very dense forest oak (casurina torulosa) too because it had what I was looking for.

Thanks for your input.

John

[Taffy Evans]

Just a few observations. A leading Aussie [factory] guitar maker uses ply bridge plates on some of their models, and some of it pretty thin. Ive had to replace a few due to the top bellying up too much.

On the other end of the scale I'm just putting a new top on a leading USA [factory] makers guitar and it also had a ply bridge plate, 5mm thick.

On my own builds at the moment I'm using timber I got in a large batch of boards from a mate. I do not know what it's called but it is white, hard and the dust irritates a bit, its 1/4 cut and has a tap tone I like. My guitars in which I have used it have good even tone, great sustain and are loud.

I also had some plate material from Gilet that was slab cut, what the thought on that, I've aways used B/plates on the 1/4.

[woodrat]

Hi Taffy, some people think that riftsawn with the grain at 45 degrees or so to the face is good because it is not as weak as 1/4 sawn down the grain. The theory being that the bridge pin holes weaken it down the grain lines and the ball ends put pressure along the same line. I usually go for 1/4 sawn but would not be adverse to the idea of rift if it had "the tap". I know the manufacturer you speak of (so does everyone else) that uses ply for bridge plates and I cant say that they benefit from it especially when a nice piece of real wood would cost less than a dollar and could be recouped from offcuts so potentially the cost could be less than that. But the people who put them together do it exactly as the bean counters say.

John

[Taffy Evans]

Too right John, I angle the grain of the bridge plate so that the holes are not in the same line as a grain line.
I'm just working on another top USA branded guitar [the bridge flew off] made in China, where the rosewood bridge plate is only 4-5mm wider than the bridge.

[Taffy Evans]

It looks like anything goes. "If you cant see it, she'll be right", another well known manufacturers blooper.

The shaded area on the bridge was the only area covered by the bridge plate, no wonder the top deformed and the bridge let go. The manufacturers did offer to do the repair, but were sorry the guitar was out of warranty. I left that one to the customer to sort out.

DSCF5506 (Small).JPG (47.91 KiB) Viewed 24167 times

[woodrat]

It looks like a case of Bridgeplatus Incorrectolocatus!

[liam_fnq]

Wow! what's the point of the massive slot

[Kim]

Wow! what's the point of the massive slot

It's for the pickup..Maton do much the same.

[charangohabsburg]

Wow! what's the point of the massive slot

It's for the pickup..Maton do much the same.

Wow, that's weird! Hilarious. It looks like the black hole where the owner's money goes in when the bridge or top does not fail within the warranty period.

[Bob Connor]

Maple doesn't have alot of 'ping' to it but it makes great bridge plate wood.

Lots of pre-war Martins had Maple bridgeplates.

My preference is for Honduran Rosewood but I recently used maple for a bridge plate. The instrument sounds fine.

[Taffy Evans]

Some Takamine's use the same pickup hole, but often a pinless bridge so less holes in the top to weaken it. And the bridge is glued and bolted on.

[Allen]

The Takamine that I put a new top on was like that one Taffy. Big slot and bridge pins.