Soundhole size and effect on body resonance

[Dave Bagwill]

Considering the spectrum of theory and practice, a fella just has to choose what works for him. I haven't had the opportunity to compare 400 guitar tops - actually, 7 so far - so I am not as trustworthy an 'ear' as someone more experienced. OTOH, the technical testing I want to do will yield repeatable results so that I can compare more closely, from instrument to instrument, what the heck is going on. Over time, perhaps the 'ear' will become a reliable intstrument for testing as well.

I appreciate your post Ray - I get it.

[Tim Benware]

So the same amount of energy results in 2x the volume; interesting. The obvious question is: why not a second port, or a third, each one tuned to the rest of the box? I must Google.

In theory it should double but in reality there is more that comes into play and it doesn't. Extra ports won't help. Think of it in this respect there are two movements of the cone (driver) forward and backward the forward facing cone takes advantage of the forward movement and the tuned port takes advantage of the backward motion of the driver by sending the reflected waves of the backward movement out the port in phase with the next forward movement. Remember, sound is fast. So no need for more than one port.

[ken cierp]

When we were selling mountain dulcimers -- the light went on regarding the increase volume and improved tone of an instrument that was place on a stand vs the same one played on the performer's lap -- the improvement was not subtle -- significant, quantum is more like it. So what I have on the drawing board is a true double back design with the inner reflective back totally insulated from the outer back. I am thinking that the inner back could be made with different woods different thicknesses, different braces etc. I know it adds to the confusion (I think of it as opportunities) --- one thing for sure the volume of the instrument will louder then the traditional guitar.

[Dave Bagwill]

Now THAT is provocative, in the good sense!!

[Dave Bagwill]

Come up with a fairly easy to install retro-fit back and it sound like you might have a winner of a product. In fact, it would not have to be fancy or shape-specific if it was adjustable. Just any sort of thin material that could affix firmly to the rim, for instance, and give 1/4" of clearance or so.

[ken cierp]

Good idea!

[TonyinNYC]

Lot's of folks would tell you that the over sized sound hole in Clarence White's D28 Brazilian made all the difference in the world....and I think it DID! In Clarence's hands.

Tony Rice, who now owns the guitar and plays it regularly, says he can't tell any difference...and I Believe him! He isn't Clarence white.
Everybody holds and plays the guitar differently.... because of that, it really does sound different.

Proof? Take ANY guitar and hold it in your lap, pull it tightly to your belly and play it....then move it away from your body so there is no contact with the back of the guitar and play it...the tone and the volume will differ greatly.

There have been thousands try to duplicate the sound of Steve Ray Vaughan and his Strat...isn't going to happen, even with all the electronics we have today, even with the same guitar...nope...his own brother admits he can't do it!

So many variables..and yet, there are SOME who can build with repeated success...why? what IS the secret?...the tech builder will tell you it's testing grain strength, thickness, bracing... the other end of the spectrum will tell you they can Just "HEAR it" they don't measure anything..they will all tell you to some degree anyway...it's the type of FINISH or lack of it...thickness...right, I've never seen a ruler on a spray gun...then there's the wood...I've seen and played one of Taylor's "Pallet" guitars (Made from an oak pallet he picked up in the lot out back) and I can tell you it was superb!

A couple of years ago in Denver, Wayne Henderson told me it was quality of workmanship and paying close attention to dimensions, properly glues joints and repeatability. From the guitars of his that I've played, including #400, he's doing something right!

Who really knows? :)

A great deal of the sound produced by a guitar has to do with the player. How many times have you had a great player pick up your guitar and you said, "That guitar has never sounded that good!" and its not the music he is playing, its how it sounds! John Mayer is a guy who can almost play like SRV, but he isnt SRV, so he can never sound exactly like him even if he owned SRV's strat.