Search found 1425 matches

by Trevor Gore
Tue Apr 16, 2019 9:06 am
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: Just closed the box - strategy?
Replies: 15
Views: 409

Re: Just closed the box - strategy?

As long as you're having fun... :D
by Trevor Gore
Mon Apr 15, 2019 9:34 pm
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: Just closed the box - strategy?
Replies: 15
Views: 409

Re: Just closed the box - strategy?

The audience will likely miss out on some bass response, but the player might not because the port will act as a "monitor" and so the player may hear a stronger bass. Maybe.
by Trevor Gore
Mon Apr 15, 2019 9:35 am
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: Just closed the box - strategy?
Replies: 15
Views: 409

Re: Just closed the box - strategy?

gerryt wrote:
Mon Apr 15, 2019 7:14 am
What I don't understand is why my T(1,1)1 is so high - currently at 109Hz
Well, don't forget the effect of the sound port. Depending on how big and whether you compensated by reducing the sound hole size, could be worth 5-10 Hz.
by Trevor Gore
Sun Apr 14, 2019 10:49 am
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: Just closed the box - strategy?
Replies: 15
Views: 409

Re: Just closed the box - strategy?

Taping bridges on doesn't tell you a whole lot. You add the mass but not the stiffness. The effect on the T(1,1)2 of adding bridges is shown in Fig. 4.6-3 (Design). For the T(1,1)1, adding the bridge typically raises its frequency a small amount on my guitars. Adding the stiffness reduces the amount...
by Trevor Gore
Sat Apr 13, 2019 5:20 pm
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: Just closed the box - strategy?
Replies: 15
Views: 409

Re: Just closed the box - strategy?

You could "blind bind" the fretboard - bind in the same wood as the fretboard, no purfling lines. That covers the tangs. Leave the end unbound.

If you thicknessed the back according to the formula, working the back brace should get you there.
by Trevor Gore
Sat Apr 13, 2019 10:28 am
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: Just closed the box - strategy?
Replies: 15
Views: 409

Re: Just closed the box - strategy?

The plots don't look much like mine but I think we can work with them. It looks like the T(1,1)1 is close to 113 Hz and the T(1,1)2 is close to 200Hz. The B(1,1) is at 238Hz, which implies that the T(1,1)3 would be around around 240Hz or a couple of Hz higher, if it were there. I guess you're using ...
by Trevor Gore
Fri Apr 12, 2019 9:14 am
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: Just closed the box - strategy?
Replies: 15
Views: 409

Re: Just closed the box - strategy?

Gerry,

Check out the last line of the last paragraph, p AI-3, (Design) for guitar holding instructions whilst tapping, then post another tap plot.

Thanks, T.
by Trevor Gore
Mon Apr 08, 2019 10:25 pm
Forum: Instrument Builders Forum
Topic: Acoustical effect of back woods
Replies: 21
Views: 967

Re: Acoustical effect of back woods

One can get very picky about the way these sorts of experiments are performed, but I'll try to stay away from that. However, trying to identify differences in sound due to the back woods when the T(1,1)1's and T(1,1)2's range over a semi-tone on non-live back instruments (no T(1,1)3's apparent, Fig ...
by Trevor Gore
Fri Apr 05, 2019 7:57 am
Forum: Instrument Builders Forum
Topic: Acoustical effect of back woods
Replies: 21
Views: 967

Acoustical effect of back woods

According to the Journal of the Acoustical Society of America (of which esteemed body I am a member) one of the most downloaded articles from the last year published in The Journal of the Acoustical Society of America is this one: “Effect of back wood choice on the perceived quality of steel-string ...
by Trevor Gore
Thu Apr 04, 2019 6:59 pm
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: T(1,1)2 and Back Question
Replies: 10
Views: 432

Re: T(1,1)2 and Back Question

Reducing to target thickness would remove about 20% of the thickness. That would of course reduce mass but also lower stiffness or is it safe to assume that the braces contribute to the majority of the stiffness? I would expect it to lower the frequency, but how much depends heavily on your bracing...
by Trevor Gore
Wed Apr 03, 2019 10:09 am
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: T(1,1)2 and Back Question
Replies: 10
Views: 432

Re: T(1,1)2 and Back Question

Kevin,

Check out pages 2-22 to 2-25 in Design (if you haven't already).
by Trevor Gore
Tue Apr 02, 2019 9:40 pm
Forum: Instrument Builders Forum
Topic: maton square head truss rod adjuster
Replies: 10
Views: 2853

Re: maton square head truss rod adjuster

Many, many years ago I made a Maton truss rod adjuster from a drum brake adjusting tool. It was a Z shaped tool with square sockets on each end, one of which was the right size. I chopped that end off and cut a slot in the stub so I could use it with a screw driver. Just did a Google search and coul...
by Trevor Gore
Sun Mar 24, 2019 12:51 pm
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: Wood for Falcate Braces in UK
Replies: 12
Views: 543

Re: Wood for Falcate Braces in UK

Some spruce will heat bend and some won't. And you can't tell until you try. That's just how it is. None of the spruce I had would bend when I first tried making falcates. But I'd heard that spruce was heat bendable and without too much trouble. When I replenished my supplies, the new stuff would be...
by Trevor Gore
Wed Mar 20, 2019 10:10 pm
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: Carbon Fiber Sheet on Bridge Plate
Replies: 1
Views: 208

Re: Carbon Fiber Sheet on Bridge Plate

There are all sorts of arguments one could put up about whether the wood should be above or below the carbon, or even whether it need be there at all. The first time I did it, I did it as per the book, and it worked well, so I stayed with it. If you put the carbon on top, let us know how it goes. So...
by Trevor Gore
Wed Mar 06, 2019 6:27 pm
Forum: Instrument Builders Forum
Topic: Weird finishing problem
Replies: 10
Views: 850

Re: Weird finishing problem

Check with Tenacious Tapes whether or not K 750 contains silicones. Some tapes do and that would explain things.
by Trevor Gore
Mon Mar 04, 2019 11:36 am
Forum: Instrument Builders Forum
Topic: Acoustic cases
Replies: 5
Views: 625

Re: Acoustic cases

Hiscox for me.
by Trevor Gore
Sat Feb 23, 2019 1:00 pm
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: To Add Side Weight or Not?
Replies: 2
Views: 306

Re: To Add Side Weight or Not?

Side mass mainly affects the T(1,1)2 resonance due to the nature of the momentum equilibrium between sides and top in that mode. Side mass will have no effect on multipole top resonances as the momentum equilibrium for those modes is maintained within the top alone. The first question when tuning mo...
by Trevor Gore
Mon Feb 18, 2019 1:09 pm
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: First Attempts: Finding Target Thickness with Acoustics
Replies: 2
Views: 441

Re: First Attempts: Finding Target Thickness with Acoustics

In general I find the plots difficult to analyses. The book gives ranges of normal values which helps. I guess you are supposed to just ignore some of the noise in the first part of the plot. Like for example in the Fc plot that first peak around 50Hz, is that just a 'shadow' of the Flc peak coming...
by Trevor Gore
Wed Feb 13, 2019 3:54 pm
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: Adapting the method to multiscale and 7-strings?
Replies: 8
Views: 805

Re: Adapting the method to multiscale and 7-strings?

What about combining a Manzer wedge with a Gore rest, to reduce the overall width? You mean the Smith wedge :D ? I've done that. It seems to work fine. I got the impression from tap test results that the air resonance wasn't as strong, as the internal pressure wave didn't build as rapidly due to th...
by Trevor Gore
Tue Feb 12, 2019 5:51 pm
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: Adapting the method to multiscale and 7-strings?
Replies: 8
Views: 805

Re: Adapting the method to multiscale and 7-strings?

I'm sure Martin will have more to say regarding your questions, Mark. One thing though, I've found that arm bevels encourage your arm to damp the top, because the bevel brings the arm closer, whereas an arm rest moves it away. Bevels can look pretty cool, though, and offer an interesting build chall...
by Trevor Gore
Tue Feb 12, 2019 5:43 pm
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: Help with my spectrum
Replies: 4
Views: 548

Re: Help with my spectrum

AKEric wrote:
Sat Feb 09, 2019 5:22 am
...would you continue to relieve the back brace at this time, or wait until the bridge and saddle are attached?
I'd leave it at the moment. It gives you more options later.
by Trevor Gore
Wed Feb 06, 2019 9:11 am
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: Help with my spectrum
Replies: 4
Views: 548

Re: Help with my spectrum

Eric, check out Fig. 4.6-3 in the Design book, Section 2.4.1.2 and Appendix VI.
by Trevor Gore
Wed Feb 06, 2019 8:49 am
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: Falcate braces - radiusing?
Replies: 7
Views: 643

Re: Falcate braces - radiusing?

The falcate braces aren't shaped on their side that glues to the soundboard. A better, more conforming surface is produced just by planing them flat. Spring-back hasn't ever been an issue for me.
by Trevor Gore
Tue Feb 05, 2019 12:33 pm
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: SS Falcate Guitar
Replies: 1
Views: 300

Re: SS Falcate Guitar

Ron, I don't sell other plans. The book is intended to be a guide that provides all the necessary information for anyone to design any type of "flat top" guitar. The plans in the book are there primarily as examples of how that can be done. So my recommendation would be to get your pencil out (or dr...
by Trevor Gore
Tue Feb 05, 2019 12:25 pm
Forum: Contemporary Acoustic Guitar Design and Build - Trevor Gore
Topic: reproducibility... or copy... of early build
Replies: 1
Views: 245

Re: reproducibility... or copy... of early build

The book discusses in detail how guitars make sound. Guitars radiate sound from their vibrating parts, mainly the top. If a guitar top vibrates in a different way, it produces a different sound. The different ways a guitar top vibrates are called modes, and there aren’t that many of them. If the mod...