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I have more experience as an engineer than as a luthier...so here's my take on this subject from an engineering perspective.

I think the functional purpose of the guitar body is to accentuate those frequencies throughout the whole range of sounds that the guitar creates. If you just wanted one note out of the guitar you would make the shape much more "regular" (either a circle or a square, or some other finite shape). By making the guitar the shape that we do, and bracing it as we do we create a variably stiff structure that is able to accentuate a whole range of tones. Things like scalloping the braces are just one more factor that can cause variation in the mass/stiffness characteristics of the soundboard...and as such it's just one more thing to throw into the mix. It will surely affect the tones...but how much and how are dependant on the rest of the structure as well as the individual pieces of wood.

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http://www.PeakeGuitars.com

SteveS...and other engineers...

Top bracing has two completely different functions:

1) Structural...to resist string pull and to maintain a reasonable semblance of the designed shape

2) Mechanical tonal shaping...EQ, if you like.   


You have to try to separate the functions in your mind to understand all that's going on.   If you look too closely from only one point of view and push it too far, you'll either have a wonderfully strong guitar top that sounds like crap, or you'll have a wonderful sounding guitar that blows up in your face.

So think of scalloping as EQ'ing the guitar top's response in one particular way.   It tends to emphasize lows and highs and because of how it allows the top to "break up" into phase/antiphase motion in the midrange, you get the familiar "smiley face" EQ that a lot of folks like to apply to an undersaddle pickup signal in order to better match the acoustic sound of the guitar.

Guitars without scalloped braces tend to have more midrange punch...which I happen to like.

Just my experience...

With all due respect, Andy, those patterns are clearly what Ervin
demonstrated in the class. To suggest that you, who by your own
admission have been building less than the two years that you have been
playing guitar, came up with those patterns of your own volition is
laughable. If the arbiter of your suggestion is how you chose to relieve
the ends of braces or minor changes in angles (incremental in my
estimation) then your claim of it being your own is rediculous. The
earliest printed version of the X with the two lower finger braces off the
lower tone bar that I'm aware of goes back to Irving Sloane who called it
the broken X bracing pattern. At a minimum that was published before
you were ten years old, and Ervin had been building for a while....

Give credit where credit is due.

[QUOTE=Rick Turner]
So think of scalloping as EQ'ing the guitar top's response in one particular way.   It tends to emphasize lows and highs and because of how it allows the top to "break up" into phase/antiphase motion in the midrange, you get the familiar "smiley face" EQ that a lot of folks like to apply to an undersaddle pickup signal in order to better match the acoustic sound of the guitar.

Guitars without scalloped braces tend to have more midrange punch...which I happen to like.

Just my experience...[/QUOTE]

That is how I prefer to use scallops as well. I get it as close to where I think I want it by thinning and tapering the brace and then to add a bit of bottom warmth I will start the scallop but usually not too radical. More of an EQ like Rick says. Most of this takes place under the wings of the bridge so what you are left with is the end of the tapered brace, what you called the stiff peak but it is really just what's left after making the EQ correction.

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Tickle your guitar daily, and it'll tickle you back.

[QUOTE=dberkowitz] With all due respect, Andy, those patterns are clearly what Ervin
demonstrated in the class. To suggest that you, who by your own
admission have been building less than the two years that you have been
playing guitar, came up with those patterns of your own volition is
laughable. If the arbiter of your suggestion is how you chose to relieve
the ends of braces or minor changes in angles (incremental in my
estimation) then your claim of it being your own is rediculous. The
earliest printed version of the X with the two lower finger braces off the
lower tone bar that I'm aware of goes back to Irving Sloane who called it
the broken X bracing pattern. At a minimum that was published before
you were ten years old, and Ervin had been building for a while....

Give credit where credit is due.[/QUOTE]

Dave,
Andy has cleary given credit to Ervin for his ability to design top bracing. Just look at the title of this thread. If you read other posts of Andy's on the subject he cleary states his strong support and appreciation for Ervin and the course.

How many different top bracing ideas did we discus and or try that week? My guess is that it would be in the hundreds? While it is true that we discussed or tried designs similar to the ones Andy has shown, to call it plagiarism is hyperbole. The fact is that Andy went home from the course and designed his bracing based on what he learned. That isn't plagiarism, that's called being a good student of the master. We looked at so many bracing schemes it is hard to imagine that anyone from the course could post something much different that what was discussed. Can you?

From where I sit, you owe Andy an apology.

You might try using email or PM with a private message first with this type of opinion before making it public.

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

Good for you, Steve.  Nice post.  

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

[QUOTE=Rick Turner] SteveS...and other engineers...

Top bracing has two completely different functions:

1) Structural...to resist string pull and to maintain a reasonable semblance of the designed shape

2) Mechanical tonal shaping...EQ, if you like.   


You have to try to separate the functions in your mind to understand all that's going on.   If you look too closely from only one point of view and push it too far, you'll either have a wonderfully strong guitar top that sounds like crap, or you'll have a wonderful sounding guitar that blows up in your face.

So think of scalloping as EQ'ing the guitar top's response in one particular way.   It tends to emphasize lows and highs and because of how it allows the top to "break up" into phase/antiphase motion in the midrange, you get the familiar "smiley face" EQ that a lot of folks like to apply to an undersaddle pickup signal in order to better match the acoustic sound of the guitar.

Guitars without scalloped braces tend to have more midrange punch...which I happen to like.

Just my experience...[/QUOTE]
Rick,
Thank you for that. I get points 1 and 2 and that those points are essential and strongly connected.

Let me see if I understand the tuning portion.
So people use the size of the peaks, length and height, to control localized stiffness as a tuning feature to in effect control mid-range? Good builders can from their experience use these peaks to control tone by tap tuning to their "signature" sound.
That must come after a lot of experience.

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

Dave
You are correct. Ervin does deserve the credit. MY ERROR   In his course we looked a vast number of patterns and alternatives. He showed us many ways to make the braces cover balanced areas of the soundboard. We all try to do our own thing but unless you go to the extreme of Smallman etc nothing will be truly original. I have made some of my own changes but Ervin certainly deserves all the credit for all of the teaching he has provided. All of us that have benefited from his expertise can certainly agree with that. Most of use an X brace and none of us came up with that idea. A lot of us use CNC to make parts but do we credit those that make stuff for us. We definitely need to acknowledge those that deserve the credit.

My appologies

I would love to thank my OLF brothers and sisters for all of the guidance they have given me over the past 2 1/2 years. Without them I would have never been able to grow like I have


Dave, How are you by the way? How is the Baritone Business?

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Andy Z.
http://www.lazydogguitars.com

The problem I have is that its not his bracing. The implication is while
Andy states that its his post-Somogyi bracing, he takes credit for a
pattern that he got from Ervin. Even your own prose belies the problem:

"Those bracing schemes are your design, not Ervin's or anyones, they are
yours right? Before the course would you have been able to do that?
Would you have even tried?
That's so cool." -- Steve


"Steve Those bracing patterns are mine based on principles that I learned
in Ervins class about how a top moves etc. Clearly they are not
Ervins He would be embarassed by my tops. I am trying new things
with each guitar. Before the course I would have never tried these
different things because I had no knowledge or foundation upon which to
create new ideas with some sort of reason behind them." --Andy

Clearly these are Ervin's patterns. From emails I got from other attendees
of this class (not necessariliy our session), some of whom post here, is
that they are in agreement with me on this one.

David
I have corrected my mistake. OK
He does deserve the credit.
Andy

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Andy Z.
http://www.lazydogguitars.com

Steve, yes, you got it.   By controlling the strong and weak areas, we can get the top to break up into it's in and out of phase motions at different frequencies.

The most extreme version of no top breakup would be a Smallman-style CF reinforced lattice bracing system.   That's a top designed for as pure piston motion as possible, and the end result is a guitar that has tremendous midrange power, and that is what makes those guitars punch to the back of an auditorium.   It also leads to the criticism of the tone as being banjo-like.

The opposite extreme would be a heavily scalloped Martin-style dreadnought which has tremendous "whump" in the bass, some nice chimey treble, and not much in the mids.   

And yes, points 1 & 2 are interconnected, and teasing apart the connection so as to be able to deal with each as separately as possible is my whole adventure in acoustic guitar design at this point. I'm looking way past the top, though, and I'm addressing the tone/structure balance of the entire guitar. For me, the top is the last thing to look at as I think that a lot of the problems with guitars are to be found in the structure of the body and neck. With those issues dealt with, then the top becomes a nice blank canvas on which to paint tone.   A lot of what I've been doing is to free the top from the responsibility of supporting the neck and fingerboard, and I find that frees me to do all the more with voicing the top.

Wow, I try not to get into these childish arguments that seem to pop up now and then, especially with the Ervin thing.

But i will just say, that David Berkowitz makes some beautiful guitars, in fact his have inspired me more than most, especially his long scale baritone.

Further, I would just say that it is a total let down to see from his above post that he comes across as a jerk.

There are proper ways to discuss, disagree, or debate opinions in a public forum.

Your comment "with all due respect..." shows that you are more like a spoiled child who does not understand the meaning of respect.

Jane...stop this crazy thing!!!!!!


George Jetson

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Andy Z.
http://www.lazydogguitars.com

Time to change my tagline. Anytime Ervins name gets brought up things somehow deteriorate.
He is such a great guy...what a shame.

He da man!!!!

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Andy Z.
http://www.lazydogguitars.com

This thread is done.

Sorry...

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