This kind of ties in with Uncle John's Graduation discussion I guess.
I'm finding that all the time I spend on my quest for good acoustic tone and volume by leaving a space between the through neck and soundboard sometimes goes to waste. After they are strung up for a while ( years maybe?) the soundboard just bends till the bridge and soundboard are now resting on the neck.
In some cases, this has actually improved the playability by lowering the action but on others that already had low action, it results in "fretbuzz".
So it looks like I may need to "Graduate" to the advanced stuff like bracing or maybe even making my own boxes or soundboards.
Do you folks think bracing helps with tone/volume or does it just result in a strong top that no longer vibrates much due to the bracing since that adds mass and weight to the soundboard? I know it is essential on full sized guitars but on the small area of a CBG.
I wonder if a small block between the bridge and neck would be better, worse or about the same as bracing. A block or a screw or something sure is a lot easier.
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I think that sustain and volume are two completely different things, right? A banjo for example has very high volume but a very short sustain, or "rapid decay" of the note, but an electric guitar may have very long sustain of the note but almost no volume (until it is amplified). For an acoustic "guitar" to sound what is considered "good" it needs to have both high volume and long sustain, for the most part I think.
It's the old conservation of energy... the more energy in the string that is converted to sound, or friction, the lower the sustain...
Acoustic strings are generally thicker, and under more tension... I suppose that contributes to a higher amount of energy imparted to the string during a pick or strum, and the resulting sustain is due to the higher mass of the string carrying that momentum...
Ok, I'm done overthinking it... They sound good either way...
I have recently built my first git that wasn't a neck through. Granted, the top was tin, not woood, but I think the process of pressure will still act the same. I needed to brace under the bridge to keep the face from bowing as I tightened the strings. The same goes for the neck through. I made mine so they glued to the face of the cigar box. So far they have given good sustain.
Brace the face along the neck and I think you will see the sustain you are looking for.
Just my opinion.....
This seems to be an ongoing conversation on this forum popping up every month or two. I'm starting to think this is one of those whatever-works-for-you things. If you're having problems with having a space then I'd definitely try something else.
From my experience (which is only 6 finished builds) the neck-glued-to-box works the best. I find it's an easier build method, better volume/sustain and I've had zero deformation of the lid. Saying that, my best build in terms of volume and sound quality was my tenor uke. That neck was fixed with dowels through the heel. The bridge-saddle was glued to the top and the top was braced. The BIG difference on this box is that I built the box from scratch and used 3mm cedar for the soundboard. I think the box itself makes the biggest difference.
I have built my cigarbox ukes and banjo using the bottom of the box as the top and that seems to give a better tone. I think the bottom wood is a better grade than the top.
Are you using paper-covered boxes? Most modern paper-covered box lids are actually masonite, not wood, ergo the bottom sounds better, even tho most of those are plywood. Those masonite tops don't resonate so well. Also, all the above (IMHO, YMMV) is moot if you're amplified.
The dowel talked about from the violin is called a sound post,and is placed under the treble foot of the bridge. It is placed there to transfer vibrations or resonation to the back of the instrument as well. This has been done for hundreds of years, so it's no suprise to find it working on CBG's as well.
There is also a rail called the bass bar that runs the length of the violin and is placed under the bass foot of the bridge. It would be interesting to see if the bass bar works in CBG's as well. A bass bar resembles a support brace from a guitar.
Thanks for the clarification Gary. I thought it was to transfer vibration to the back of the violin, but didn't have any specific references. This could be a very good thing for CBG volume.
Thanks for sharing your experiment Jim. Your result is why I have always left a space between the neck and box. They start off sounding more like your no dowel sample and end up sounding more like your with dowell sound as the top collapses and touches the neck. I don't know if in this case the dowel being under enough pressure to lift the bridge a bit makes any difference or not but your test seems pretty convincing for a gap.
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