Acoustic Guitar Construction in the small shop -- Kenneth Michael Guitars LLC

Information, ideas and help for those constructing scratch built acoustic guitars or acoustic guitar kits - © 2017
It is currently Thu Nov 23, 2017 9:51 pm

All times are UTC - 5 hours [ DST ]


Forum rules


The purpose of this forum site is to provide a means for acoustic guitar makers at all skill levels to forward information, share experience and ask questions if project obstacles are encountered. We ask that egos be left at the door – the highest levels of courtesy and respect are to be shown to all. Posts containing disparaging comments will be removed. The “Acoustic Guitar Construction Forum” is owned by Kenneth Michael Guitars and is copy protected. Direct links to luthier suppliers are not permitted and will be edited.



Post new topic Reply to topic  [ 5 posts ] 
Author Message
 Post subject: Increasing volume?
PostPosted: Thu Oct 15, 2015 8:33 am 
Offline

Joined: Mon Oct 12, 2015 8:21 am
Posts: 2
Hi,
I just finished my first guitar. Although happy to finally got it togehther im a little bit dissapointed in the volume of the guitar.
What parameters would one elaborate with to increase the volume? Im thinking soundhole dimension, body depth, bracing etc would all play a part but I have no clear idea of how these parameters should be altered.

The guitar is an OM based on martin drawing with Germans spruce top/chechen bs.

Best regards, Daniel


Top
 Profile  
 
 Post subject: Re: Increasing volume?
PostPosted: Thu Oct 15, 2015 9:00 am 
Offline

Joined: Tue Dec 13, 2011 11:23 pm
Posts: 3924
Who's drawing?

If its Scott Andes version you can pretty much assume that its way over braced. Shaving braces on a completed guitar is a "pita" but can be done -- there's info on the internet and also in Don Teeter's repair publication.

Personally I'd start by thinning the perimeter on the lower bout -- generally getting the outer 1" or so down to .08" or a little less really free's up the sound board and all kind of good things can happen.

_________________
ken cierp
http://www.kennethmichaelguitars.com/
Store Front
http://www.cncguitarproducts.com/
KMG Guitar Kit Information
http://www.kennethmichaelguitars.com/kitinfopackage.html


Top
 Profile  
 
 Post subject: Re: Increasing volume?
PostPosted: Thu Oct 15, 2015 9:08 am 
Offline

Joined: Tue Dec 13, 2011 11:23 pm
Posts: 3924
Also don't over look the some what obvious here --- just because you like or are accustom such and such strings does not mean they are right for this guitar. So ---- what I am saying is that before modifying the instrument try a little heavier strings, even changing one or two in the set can be dramatic. This is a tip I got from Bob Taylor years ago, I had a disappointing 815 model -- his simple tip worked like magic.

_________________
ken cierp
http://www.kennethmichaelguitars.com/
Store Front
http://www.cncguitarproducts.com/
KMG Guitar Kit Information
http://www.kennethmichaelguitars.com/kitinfopackage.html


Top
 Profile  
 
 Post subject: Re: Increasing volume?
PostPosted: Thu Oct 15, 2015 9:42 am 
Offline

Joined: Mon Oct 12, 2015 8:21 am
Posts: 2
Yes i have that plan but the bracing is motsly based on this drawing:
http://www.best-eurospruce.com/resource ... tar_en.pdf
with the x-brace 1 inch from the soundhole and about 1/4 thick braces. The only difference is that mine has about 1/2 inch deeper body. I thought that would increase the volume but maybe im not thinking right?


Top
 Profile  
 
 Post subject: Re: Increasing volume?
PostPosted: Thu Oct 15, 2015 11:15 am 
Offline

Joined: Tue Nov 27, 2012 8:01 pm
Posts: 727
Location: Kalamazoo, MI
Daniel,

You have reduced the width of the top braces, which should help, not hurt. Shifting the X forward a tiny bit as you did should not hurt volume and might boost bass a bit. Likewise adding depth to the body should help both, especially bass response. Everything Ken says should boost volume. Heavier strings are easy to try. I would add three considerations for the future:

1. The two lower back braces (.39" wide x .75" tall) seem very large to me and might be interfering with the back's contribution.

2. .11" for the top seems reasonable, but if volume is a problem, then maybe go a little thinner overall and be sure to follow Ken's suggest for thinning the perimeter. In any case, the lack of at least a Popsicle brace under the fingerboard, even on an OM, seems like it leaves upper bout underbuilt. Adding weight in the form of stronger bracing under the fingerboard should not affect volume much, if any. If you are thinning the top by hand the upper bout can be left thicker with the lower thinner to gain volume without compromising strength that much. You can also thin the lower after getting the basic thickness by careful sanding once the top is braced, going by "feel" or by actual measurement or both. Measurements are possible, even after gluing the top to the rims, if you have one of several gizmos for measuring in that circumstance. I have an electronic one that uses a magnet and steel ball that seems accurate. It certainly is easy to use, even if the back is also glued on. It was expensive, but worth it because it takes the mystery out of the "feeling" approach so that I have a better idea of what I am actually doing. If you like checking out the dimensions of other guitars, it is indispensable.

3. Finally, the two sound hole braces between T1 and the Xes could be thinner, but taller, instead of wider but flatter. For the same amount of wood you would get better transmission of the stress from the strings between T1 and the Xes. From a structural point of view, the soundhole is traditionally placed in a very problematic spot, though it looks great there. In practice, the upper bout does not vibrate much when compared to the lower bout, so adding weight to get resistance to the collapsing effect of string tension does not hurt volume and tends to enhance playability by stabilizing the action, once it is set.

In summary, it looks like you are at the point where minor changes might make a fairly large difference.

_________________
John

http://brokenheartguitars.com


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 5 posts ] 

All times are UTC - 5 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group