The Luthier Community

Hey Todd,

Nice looking twins. Smoking rosettes! How did you do the little crossing on the sides of the rosettes?

Erik

You install in this order*:

1. Inner wood, for me it's 16 pieces grain out.
2. Then I route the outer rings and install them.
3. Route the inner cavities leaving the .75" transition off.
4. Carve the transition for one ring (inside-out on one side and outside-in on the other).
5. Install (glue in) that ring, and a filler strip.
6. Cut through the band and carve the transition for the outer ring.
7. Install middle and outer ring.

*Design the idea for the rosette (as a spin off of a friends design of the back twist lines) and have him CNC it with permission.

Video of Rene Izquierdo, classical instructor at the UWM playing the Adi twin.
http://www.youtube.com/user/ToddLGuitars

So I had to revoice the Cedar as it sucked. I posted in another location but thought it might be good to post here too.



So I took Bryan Galloups "Dynamic Voicing Seminar," http://www.galloupguitars.com/featured-seminars.htm#top and I'm writing a story for the FJ on my time there, but needless to say I'm in a whole other rabbit hole nowadays as far as my voicing knowledge goes. I've had this Cedar guitar that I built for Healdsburg 2 years ago and I built it with a twin that had the same BRW flitch matched back and sides but had an Adi top. To Be honest that guitar kills and this Cedar is simply OK to BAD (Boring).



Same Bracing, same pattern, but the the top was set to my Cedar thickness (before my voicing education) and the back was a little over sanded. There was a nail rust line that I thought was just oxidation and as such thought I could just "sand it out." Wrong! Anyway the back was left a little thinner but still in the normal range acording to all the specs that everyone tells you for a Steel String back.

But now the knowledge of what my back and top should be doing has hit and I've found that my top is the same tone as my back with the bridge glued on and the saddle and pin weight in so they are acting as buffers constricting each others movement rather then complimentary partners in moving the air.

The main problem is that I didn't know what I was doing in bracing my top and back. Not many builders do in the beginning I think. I went to my favorite builders shop looked at his guitars tops. Measured his braces: their thickness and height, placement as they fanned and connected to the x-brace over the top and sides, and scalloped them exactly like he did, same bridge plate design and proportion, it should have been good, right? It should have sounded like his, right? I used Cedar I bought from him and BRW I bought from him. I expected the same results that he gets. WRONG!!

It's kind of like what everyone else does (Younger builders especially- "younger builders" being less then 50 guitars). Make a Martin: X-Forward or X-Back, 5/16-1/4 brace thickness depending if you like "Vintage" or "Modern," scallop like this,... the reality is wood is wood and no two guitars sound the same. Densities are different, Speed of Sound is different in those densities, Modulus of Elasticity (the ability to flex under force) is different. I'm not talking Sitka to Red Spruce different, I'm talking Sitka top 1 to Sitka top 2; same tree same flitch.

This cedar guitar of mine just SUCKS!! At least for what I want and know it can be. OK, it sounds great but it doesn't project well and it doesn't vibrate with my hands as I play. I don't feel connected to it as I play. It doesn't make me want to play it until my arms fall off. It's a good guitar but not a great instrument.

Part of the problem is that I used an African Blackwood bridge which is heavier then my usual ebony bridge. Know your bridge weight with saddle and pins. Weight is a damper and top tone note lower'er, a gram here or there makes all the difference. Be aware!!

So to remedy the guitar I'm going to shave my top braces to lower the pitch of the top to the intervole I want it to be set apart from the back, I'm planning on taking pics out in the shop tonight as I revoice but there's only so much I can say, and show, without stepping on the toes of my Teachers. But it'll get your mind going enough to see what's happening.

Yes it's a big tease but we don't talk about voicing as clearly as we could and this might help some of us see "what's next." What more of us could start paying attention to.

Got it done tonight and man it's now amazing, dead strings and all. I took pics before I started shaving and after. Now that I know how to voice properly before I get the back on I won't have to do this again but it's nice to know that I can fix a BAD sounding guitar.

Here's what it sounded like, sorry I forgot to play it with strings on.


Now my Back started at a Sharp G# to in tune G#. So and G#3 +.35 to .06c. There are 100 cents between every half step so I was right on the cusp of it being a sharp G. (Just 57 cents away.)


Which is what the Top was, G3 +.41c to +.76c.


So the top and back we're really just, on average, 40 cents away from each other. Which is waaaaay to close. And being that close the top and back basically got in each others way. The air pump couldn't function because both doors were opening and closing at the same time, creating a vacum... so to speak. Neither one could move at it's optimum.

Here's what the braces looked like before I started to shave them down. They looked so clean and pro, right?!?!




First off: When shaving braces you want to shave width not height. Tone is carried in height so the taller your brace is the more tone you'll allow to travel down the length of the brace, the more tone you'll maintain in your top. Now when you can't can't shave anymore width then you take height. Your taking off weight to allow the top to vibrate more which lowers the pitch.

Start by shaving down the X-brace. If you use an X Brace it is your "Tone Setting" brace. Your other braces (Finger braces and Tone bars) are your "Tone Affecting" braces. Think of it this way, high school choir style, sing a D on the word La. Now Sing that D on the word Lo (Low). The X-brace is your D note, it sets the majority of the sonic area for your top. The tone bars and finger braces affect the way that D note is delivered (going from an A sound to an O sound). Obviously eliminating the tone bars weight will lower note of the top, I'm just saying that the tone bars-- for the most part, affect the tone of the note set by the X-Brace.

Here's what happened after I took a small amount of shavings off from the X-Brace only. I kept the shavings so you could see how much I actually took off.


So there is a lot of control left out there to explore. Knowing the intervals you want your top and back to end up at is essential. Because just like mine were too close together, they can also be to far apart. Where rather then working together they just wobble and shake for the sake of shake rather then for the sake of projection and tone transfer.

They're not pretty now, but my guitar sounds better then most now.




Now, the most important thing to go by is that I took these braces down to a point where the top gave me a specific tone. The shape, the scallop, and the layout of the braces don't really matter as much as the the way you link the back and the top together.

The end result: Monster volume and clarity. Definitely not the BS tone I had before. It was good but not exciting. Guys would play it and gave it right back. You can see me playing it on the video and I can't stop until I'd heard a full phrase of my tune. I was confused about how great it sounded. It's inviting and raucous,warm and brilliant, I'm finally proud of it. I'm not over selling here, you can hear it when I strum the stings and my Iphone Mic shows you how great it became. Do it to your Guitars, check em out, see what your tops are and your backs are pitching at. If you really want to study it and be able to link it all to great tone call Bryan Galloup and check it out.
http://www.galloupguitars.com/school.htm

There's so much more to this in the building stages, it'll blow your mind. This is just the fix; a correction for a bad guitar. New construction, it's insane what you can control and Bryan and Sam's system is an an actual set your numbers here and your parts there and you can then control your tone. It's INSANE!!!

A little Background on what the logic is behind this before I show my results. Bryan and Sam have spent the last 5 years working on voicing. They measured the tap tones from their favorite builders and favorite guitars. Old 1930's Martins, old killer Gibsons, and modern day builders that sell for high, high dollars. They found that most of the guitars they loved fell in a specific intervallic range and the guitars they didn't like were way outside that range or too close together (like mine). If you don't mind a little math, and want an actual layout of how-to, do yourself a favor, builder to builder, and check them out. I may be down a whole other the rabbit hole, but man I feel like I gained 5 years of better guitars in an instant.

Thanks guys, I'm so stoked on my build potential I feel like I have to share. It's insane what I just did. Insane!