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So,they built their guitar too weakly,and used the doctor to shore it up? Frankly,I really don't care what their motives were. I try to build them right,as do the 99.9% majority,without having to resort to such crutches.

George,

Your personal preferences for sonic choices other than a Breedlove aside, what difference does it make? There are examples of designs where the structure of the design was inadequate and made up for in some other fashion -- Greg Smallman comes to mind with his wafer thin tops, balsa wood braces and graphite glued over the top of his braces to make up for the fact that there wasn't enough structure. That Breedlove does so in a non-traditional fashion is immaterial to the fact that their instruments function as intended -- they play in tune, have good action, are balanced in their presentation note to note and across the fingerboard, have more than acceptable volume, and their top doesn't dive down.

Every approach to instrument making involves sacrifices, including traditional scalloped top bracing. On average, a traditional scalloped top guitar will have a warm woody presentation when compared to say a Somogyi, which does not have scalloped top bracing. That being said, the Somogyi will have better note-to-note separation and clarity across the guitar's range than a traditional instrument. That is not to say the Somogyi isn't warm but rather that his approach garners a greater level of clarity than the inefficiencies inherent in the traditionally braced guitar, but it does so while losing some of the woodiness or rather the frequency components that we generally identify as "woody." I'd argue he dialed out the frequencies muddying up the presentation.

By the same token, Breedlove's gain a change in their attack transient at the expense of the percussive presentation of traditional instruments. That they do so in a manner that continues to be successful despite your consternation at their approach is immaterial to that success. It's not for everyone, any more than yours or my own instruments are for everyone.

In sum, why does their choice make their methodology wrong? Remarkably, of the guitar companies started at the beginning of the 1990's, they are one of the few still standing and that's saying something. A number of very fine artists have of their own volition chosen Breedloves -- Ed Gerhardt, California Guitar Trio (who incidentally played Somogyi's too), Alex Degrassi, and so forth.

Breedlove chose to build a different kind of guitar -- that it isn't a Model T doesn't make their approach wrong, it merely makes it wrong for you.

If I may comment on the Bridge Doctor system.

We've been using them as standard features in the last few (4) guitars we've made, and the tone is anything but shoddy. In fact, I feel that the guitars that have had these bridge doctors in them sound better than the guitars that have not had them.

To be fair, we have also been experimenting with channels routed in the top, similar to Taylor's relief channel, for the same amount of time, on the same instruments. This could account for the richer tone alone, not the bridge doctor. Although I do not believe that the bridge doctor has any detrimental effect on the tone of my instruments.

Understand, I am 18 years old. I am working on only my 10th guitar. This is only my unsolicited take on the doctors so far - ask me again in 10 years, 100 guitars from now, and I will have a better idea of it's true effectivness.

_________________
Jake

~Make a joyful noise unto the Lord~

Congratulations! You go get em'.

I have a question. Do you make your own? Or do you use the store bought ones? Stew Mac? How much do they weigh? Any thoughts on tone, for better or worse, if the rod hits the tail block in the center of the block? Or more towards the back? Or the top? How far away is the rod from the top at the bridge?

Thanks!

Glen

We do make our own. The design with the JLD is basically, what you see is what you get. There aren't really any secrets with it. It's basically a chunk (such a crude word, but what can you do?) of wood screwed to the bottom of the bridge (the bridge is still glued to the top, obviously), and a longer dowel rod that runs to the tail-block, which has a corresponding hole drilled into it to allow the rod to seat. The chunk hanging from the bridge, we use a nylon screw and brass inserts to allow the user to tweak the bridge up and down if over time humidity or pressure take it's toll on the bridge position. We use a hex cap screw behind our string ports on our bridge (we use a pinless design) and sometimes it is covered by a dot of ebony, or other appropriate material. You could save time and stress buying one, but I like to make my own everything, if i can - that way I KNOW it is compatible, and I KNOW it is what I want.

As far as tone and such goes, like I said, I only have completed 4 guitars with this setup. The guitars have all sounded great, but there are other factors coming into play too. We (this is my Dad and I's hobby) have also been using soundports, relief cuts (akin to Taylor's relief cuts on thier tops) and we have taken a 1/8" off our bracing width (we were bracing way too wide), we've been using x bracing on our backs too. We've kinda revolutionized the way our guitars have been built all at once. I do know that the guitars sound fantastic, and those who have played them have really enjoyed them.

The bridge doctor isn't a "right" or a "wrong." It is simply a "difference." Just like tap-tuning or dove-tailed neck-to-body joints, some do it, some don't. Just do what works best for you!

I'll post some pics too, maybe they will help.

_________________
Jake

~Make a joyful noise unto the Lord~

Here is a picture of the bridge

_________________
Jake

~Make a joyful noise unto the Lord~

Removing or disengaging the Bridge Doctor in a Breedlove guitar will void the warranty and
will also put the guitar in jeopardy.

The Bridge Doctor is secure using a screw through the bridge and top and the Spruce rod
rests against the front of the rear block to provide resistance to the torque forces on the bridge
and the top created by the strings' tension.

The beauty of a Breedlove guitar with the standard Bridge Doctor installed is that the top
has been braced exceptionally lightly and voiced with the additional structural aid provided by
the unit in mind. A Breedlove that was built with the Bridge Doctor installed will be in danger
of top failure if it weren't in place.

It's a very practical device that has served the repair industry by allowing repair people to
pull a distorted top on an older guitar back into shape and to prevent a bridge from doing
damage that is beyond repair. I've installed over 50 of them and every guitar owner was
very happy with the addition of them to their guitar. They also noticed an improvement in
tone, volume and intonation of their guitars after the installations.

Regards,
Kevin Gallagher/Omega Guitars

Consider this:
The pure compressive and tensile strength of Spruce gives most guitars a 20:1 or greater safety factor........ A guitar *Never* fails from the top tearing behind the bridge or crushing in front of the bridge... *Ever*

When the top is built way too light... what failure mode do we see? Torque at the bridge causing the top to buckle in front of the bridge..... but most guitars are designed with at least a 6:1 safety factor resisting torque here too.... They usually don't collapse, but end up sounding tubby.

Think of an empty Coke can... A 200 lb man can stand upright on 1 empty coke can... if the sides are intact. Once the side buckles... The whole can crushes instantly.

Same thing going on with a Bridge Doctor on an *Extremely lightly* built guitar... The JLD basically twists the top back flat.. Puts the top back into pure tension/compression rather than allowing it to buckle.... This mostly keeps the bridge from "Rocking" and pushes the intonation back to where it needs to be.

Now... in a properly built guitar that doesn't need the help... it just adds weight.... which may be why it sometimes seems to help out those cheap-o tinny sounding plywood wonders.. Glue about 1-oz to the bridge and it would probably sound about the same.

That's my mental model for what is going on at least...

Thanks

John

It is true that a Bridge Doctor can rob a little bit of tone if a top is already braced heavily, but
chances are that the reason for top distortion in front of and behind the bridge under string tension
is that the top was too lightly braced or has been under excessive string tension for a long time.

The large hump that is fairly common behind the bridge on guitars is usually accompanied by
the dropping of the top in front of the bridge toward the soundhole. It is failure of the top even
though it doesn't and in a catastrophic event like a bridge lifting and tearing off or the top pulling
away from the kerfing and coming off of the guitar. It is an absolute failure, in any case and no matter
how you explain it, and it can be recovered from to a good degree with the installation and the
proper adjustment of a JLD Bridge Doctor unit.

It's amazing how far from correct that the intonation can wander when the bridge is allowed to
roll forward as the saddle is used as a lever to work on the fulcrum that is the front edge of the
bridge as the strings try to pull it off of the top. The top surrenders, the bridge rolls forward allowing
the top edge of the saddle to close the gap between itself and the nut. I've repaired lots of guitars
with this condition and the Bridge Doctor is the least expensive, least destructive and easiest
solution available.

It is also a very lightweight unit that actually aids in the vibration commnication between the
components of the guitar's body. It can actually offer an increase in volume, sustain and projection
of a guitar when installed. The whole weight being a tome robber argument really doesn't apply
since the function of the piece promotes the transportation of vibration from the highly active
area under and around the bridge to the rear block and, in turn, the back and sides of the guitar.

Since all of the parts of a guitar contribute to various degrees to the tone and volume of the
guitar, it serves to purpose that anything that physically activates parts that may otherwise be less
affected or even static, will contribute in a positive way to the tone and operation of any guitar
that it is in.

Regards,
Kevin Gallagher/Omega Guitars

I make classicals and I was planing to make a under-built acoustic with a bridge doc inside, and many opinions in this thread are very encouraging to me!

CW, I would actually recommend against that. Bridge trusses add mass and change the attack transient of the guitar rounding its presentation. This is fine in the context of a steel string that has high frequency energy to spare; however, in the context of a classical where the overwhelming desire of builders and players is to get strong trebles which don't come without effort on a classical guitar, adding a bridge doctor of some kind (even scaled for the classical) would be counterintuitive. Everything classical builders do is to reduce weight so the top can move quickly -- thin tops, rosewood bridges (less weight = less damping = less contribution to low end frequencies), so adding something that would both dampen and restrict vibration would be a mistake in my estimation.

Thanks for your concern, but I meant I'd like to try it on my steel string which is yet to be built.

Sorry, CW. Missed that. --db

[quote="Jake Archer"][The design with the JLD is basically, what you see is what you get. There aren't really any secrets with it..
quote]

I was wondering, since the weight issue comes up quite a bit, what would happen if you cantilevered the block to the North? Wouldn't more of the weight be hanging off of the front of the bridge? Might change something tonally for better or worse? Or if you reversed it and had the weight hanging to the South? And it would weigh less because the rod would be shorter? And with the option of leaving it hanging straight down, that would be three ways to do it on one guitar? And if you made two sets of each, one out of mahogany and one out of bass wood, six ways to do it on one guitar?





Why does the big hunk of wood have to hang down so low? I would change the name of "big hunk of wood" to "slimline tone enhancer" or something like that. If it was shorter leaving the rod closer to the bridge, wouldn't it take more force on the rod to rock the bridge flat? Hence driving more of the vibrations or whatever into the tail block? Or would it need to come down so far to find a sweet spot that works better? And would it change anything if the rod hit the tail block by the top, in the middle, or on a piece of homemade kerfing with a hole in it where the back and the tail block meet? One way might leave the guitar more responsive for finger style and one way might leave it better for heavy strumming?

I could do all of these experiments myself but, since you are right there thinking about it and doing it anyway?

Glen

I dont see much difference in how the weight of the unit hangs .. its still just a mass hanging from where ever the thing attachs. If it was heavy enough, liek a piece of steel, then it would impart its own torque to the bridge - but not made out of spruce - too light to really ahve an effect. Making it shorter wont do much either IMO, the reason its longer in the first place is simple physics .. torque = force x distance ... so with the longer piece hanging from the bridge, the less force it will take on the rod to correct the top's belly - which is what these things were designed for in the first place.

Note - David doesnt use it to correct top belly in his baritones - he uses it to alter the attack of the notes. I like the way mine sound the way they are .... so no JLD for me.

I also dont see how where it hits the tail block will make any difference in tone ... the tail block adds nothing to the tone of a guitar, its pretty inert I would think ...

Also your S shaped piece will actually weigh more than if it were just straight like the real thing ... so making the rod shorter is offset by the added wieght of the block.

_________________
Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Hi Tony

Thank you for the response.

I don't see much of a difference on how the weight of the unit hangs either. But it might make a difference. And it might not. What's a couple of grams one way or the other? But when you strap strings to it and hit the big E chord, it might make more of a difference when the thing is bouncing around all over the place. Then again it might not. Maybe it should be made heavier to impart it's own torque on the bridge one way or the other? Who knows?

I'm not thinking that we are going to put a bridge doctor in a Gibson L1 and have it blow away all of the guitars at the next Montreal guitar show. I don't think that that is going to happen.

Actually I could care less if someone put a JLD in one of their guitars or not. But if someone brought a guitar to my shop that needed one, I would certainly like to have some info about what to do, and what not to do, with one before I went hacking into someone's family heirloom. That one I would care about. A lot.

For example: Say someone had an old guitar that they wanted to, or needed to, put in a JLD. If installing it one way killed 15% of the total responsiveness of the guitar, and installing it another way only killed 5% of the total responsiveness of the guitar, wouldn't it be nice to know which direction to head for from the start? And what if someone figured out how to make the guitar 5% more responsive with a little bit more bass with one? And then shared their findings with someone else who in turn learned something else from it? Wouldn't that be cool? It probably wouldn't make the Gibson king of the next Montreal Guitar Show. But it should make the owner of the Gibson about 5% happier.

Less force on a longer hanging piece to correct the tops belly makes sense. What is the difference in poundage to correct a tops belly with the rod 2" from the bridge as opposed to 3" from the bridge? How much poundage does it take to correct the belly in a top? Does anyone know? And how do you measure it?

"I also dont see how where it hits the tail block will make any difference in tone ... the tail block adds nothing to the tone of a guitar, its pretty inert I would think ..."

I would think that the tail block is not inert. When I play my guitars they vibrate from the end pin to the tip of the headstock. And the tail block is right in between those two points. If doing something as simple as cleaning the dirt off of a guitar, or changing the bridge pins from plastic to ebony, will change the voice of the thing, one would think that changing the tail block from bass wood to cocobolo should do something. One or the other should be filtering out certain frequencies more then the other. Let alone stabbing it with a rod that is connected to a big heavy block hanging from the bridge. We all know what happens to the tone when we add weight to a tail block.





I don't believe that the S shaped block is going to weigh more then the straight block. For one, I don't know how much a bridge doctor weighs. And I have asked. And I have not built an S shaped one yet. I'm pretty sure that with some space age technology and some hide glue, I should be able to laminate something together that is just as strong and lighter then a square block. Maybe T shaped. The part that hangs down only needs to be wide enough to hold the rod? And maybe drill some holes in it to make it lighter yet. Which might make it strong and flexible. Which might work better yet.

I'm not trying to be argumentative. I was just wondering how these things work because, I have one of my guitars that someone left in the hot car in Arizona with medium gauge strings on it about 500 times. And it is going back for more. I may need to be putting one of these things in it soon.

Thank you for giving me some more things to think about.

Glen

The earliest Breedloves had bridge trusses made in house. These were a wider block that tapered both back and down and had a smaller dowel. Then there was an adjustable, i.e., distance between the two contact points, that was made with wood and PVC -- not the best system. Then they changed to the current model which isn't perfect, and I modify mine.

I'm not sure what advantage one would get from the aforementioned "S" shaped block. There's more than enough leverage as it is. I think adding mass would be counterproductive. You're already adding probably 20g extra weight that you would otherwise no have, and you have the resistance of the dowel resting on the endblock. Properly adjusted, this dowel is only tight enough to keep it from rattling and the dowel can be rotated by hand with no string tension. Adding mass would further restrict vibration. If there was a way to have it functional and not have it be as heavy, that would be better.

Another reason for the long block is so that the dowel can be below the centerline of the endblock so there is room for the end pin or jack.

Some good ponts David ....

on my previous post .. the unit, if the width is the same , has to weigh more in the S shape - there is simply more side area vs a straight one - might not be much, but its there.

does adding mass via the cam clamp anywhere else on the body edge do the same thing ?? - if so, then the neck block really has no effect - its purely the mass of the clamp. I understand the sides vibrate, that makes a bunch of sense, but they dont add to the guitars tone like a back or top does.

_________________
Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Can this bridge doctor be used on a lattice top classical? I have e that has a rolling bridge. The a guitar top below the bridge is raised a bit and is indented slightly in front of the bridge. Pats post of a TUBBY sound with little sustain is exactly what this guitar has. Is this a potential fix?
Kent Bailey

_________________
Wood Creations by Kent A. Bailey
EXCELLENCE IN SCULPTURE, CARVING, LUTHIER, ARCHITECTURAL MILLWORK AND DESIGN

http://www.kabart.com

So if I reversed the rod making it pull from the neck block instead of pushing from the tail block that would change the tone???????????

I guess I have some experimenting to do?

Thanks!

Glen

Kent, the guitar is tubby probably because its underbraced in some fashion. You might try using different strings, higher tension and perhaps composites. This will help. The Bridge Doctor wasn't really designed for what you're dealing with.

Thanks D!

I suppose I could angle the rod any direction that I wanted to. Landing it just about anywhere inside the box that I wanted to. Might have to glue in a little block with a hole in it to keep the rod from sliding around. That would be easy enough to do.





Glen

Interesting: this discussion ranges from, "Those can't work", from those who have no experience with JLD, to, "Here's how they work", from those that do.

Breedlove guitars sound terrible, and have failed in the marketplace--and it's all the fault of the JLD, right? Heh heh...

_________________
https://soundcloud.com/jeffreylsuits/he ... -runnin-13

First:
A couple of grams one way or the other at the bridge can make a difference in the tone. I'd think keeping something like the Bridge Doctor as light as possible would be a good idea.

Second:
There's a world of difference between the forces the BD puts on the tail block, and what you get from adding a honking big clamp. I have known some very smart people, and good guitar makers, who added weight to the tailblock to reduce it's motion. The best one I know gave it up after a while, as it didn't seem to make much difference, but the reasoning behind it made a lot of sense.

The BD is mostly pushing the block in and out along the center line of the box. I've never seen a structurally sound guitar in which the block could move much in that way, so I question how effective that could be in producing sound. OTOH, these things are complicated enough that almost anything could happen. I'd want to see some good strong documentation, though.

[quote="Alan Carruth"]First:
A couple of grams one way or the other at the bridge can make a difference in the tone. I'd think keeping something like the Bridge Doctor as light as possible would be a good idea.
quote]

I would think so too. I wouldn't be above replacing the bridge with one made out of Koa to keep it all a little bit lighter. Having the rod pull from the neck block instead of pushing from the tail block, you could use a thinner rod? Saving some weight there too? But then the guitar community would probably scream like a gut shot cougar if you could see the rod through the sound hole. And you could probably save more weight, make the rod almost invisible, get the needed pull from the neck block that you needed, with a couple of strands of dental floss. And then there would be the big debate about what sounded better? Waxed dental floss? Or un-waxed dental floss?

I'm just thinking about how to put one into an existing guitar without changing the voice of the thing. Or, if it makes it better, that would be cool too. Or which way would be the least destructive to the voice of the thing. Any ideas of how to do that, or what not to do, from anyone, would be greatly appreciated. Of course, having no one else see or hear the guitar first, it would all be speculation at this point. But I'll take what ever I can get.

Thanks everyone.

Glen