Body shape and sound

[s_wood]

I own some Series basses with sold bodies, and some that are hollow, and there is an audible difference. I also hear an important difference between certain top woods, such as quilt or flame maple versus cocobolo, while other top woods make less of a difference. Like pclifton implies above, my experience has been that most careful Alembicians would be able to hear the difference between maple and cocobolo.  
 
There are, of course, lots of other important variables. The effect of ebony neck lams, particularly when more than one is used, is pretty profound.  Finally, there's a noticeable difference between a neck made primarily of mahogany and one made primarily of maple.    
 
And all of that is before we talk about the type and age of the strings used - not to mention amp, speakers...etc.  
 
To answer your original question, though, I doubt that the shape of the body matters much, although mass (which can be related to body size) absolutely matters.

[bkbass]

Ibanez did a computer analysis of body vibration I think during the late 70's possibly 80's. Anyway, It showed the various resonant areas. I seem to remember the upper bout or horn having an additive effect on the lower notes. If this is true then it would appear that shape does in some way affect the sound.

[artswork99]

Vibrational Analysis of Guitar Bodies (PDF) from the University of Illinois.

[mike1762]

Thanks for the link Art.  It's been a while since my last physics class, but I could sort-of follow the study.

[lbpesq]

The results suggest that electric guitars do not vibrate in the same way as acoustic guitars.
 
I suspect these guys aren't guitar players.
 
Bill, tgo

[mike1762]

Bill
 
I think you are right, the authors were probably NOT guitar players... it was an study approached from the perspective of basic science.  Was there something about the discussion and/or conclusions that bothered you?

[lbpesq]

Not bothered at all.  Actually I found the article very interesting though, admittedly, I just skimmed it.  I just thought the opening conclusion was amusing in it's obviousness.  Sort of like Scientists concluded that an electric guitar plugged into an amp is demonstrably louder than the same guitar unplugged, or those sports color commentators who come up with such insiteful comments as scoring more points helps you to win.  No disparagement intended.
 
Bill, tgo

[David Houck]

John; that's a great idea you have for us sending our Alembics to you for the comparative analysis.  But it's already been done, by Mica.
 
As Mica has stated often, and as mentioned above by Steve, some tops make a difference in the tone of the instrument, and some tops don't.  And as stated above by several, tops such as Cocobolo and Maple contribute significantly to the sound; other woods not so much.  You are of course correct in that neck woods contribute more to the sound of a neck through instrument than do the body woods.  However, there is a significant difference between a neck through with a Mahogany body and the same instrument with a Maple body.  The choice of other core body woods will also change the tone of the instrument.
 
Of course on the most important contributors to tone is the choice of fingers.  I'm always surprised at how great my basses sound when someone else plays them!

[lbpesq]

Dave:
 
Obviously, you've never heard me play your bass!  hehehehe
 
Bill, tgo

[David Houck]

Bill, it would probably sound better than me trying to do something with those really thin strings of yours.

[mica]

Just about everything impacts the sound. In my experience, mass is the most meaningful, but I'm certain that the shape itself will contribute as well.  
 
Just how much, and how to talk about it would require more careful observations and test instruments to be made for the control. Make everything the same except for the body shape, using wood from all the same lumber. Could make a nice collection
 
As far as wood overall, in Alembic basses and guitars, I find the neck is the most pronounced place the wood affects the tone. On a fretless bass, next is the fingerboard. On a fretted guitar or bass, next is the body wood (that's the core and the laminates).
 
I have been carefully studying the last several hundred Alembic basses and guitars, and I have learned to hear many things that were not obvious to me a few years ago. Coco Bolo is incredibly distinctive, as is Quilted Maple. Koa is unmistakable. A Mahogany neck gives itself away easily, but the body wood variables blur a little when paired with it.  
 
In the end, the best advice is to select woods that won't fight against the default sound you are seeking to avoid a major custom blunder. For instance, an original all-Maple Essence is probably not a good choice for a typical country band, but can be stellar with rock. If you like the look of Koa, but the warm sound with less pronounced highs is exactly opposite the tone you are trying for, then you shouldn't use it except for a decorative veneer on the peghead.
 
Though I've watched hundreds of basses and guitars through the real time spectrum analyzer, and my sensitivity to changes in tone from wood has expanded, I'm always learning more every time I try. So please, listen to as many instruments as you can and if you're really interested, keep a notebook with your observations, it's very useful for reference.

[white_cloud]

The human ear is an incredible piece of biological engineering - each being custom made by mother nature!!!
 
Your ear will never lie when telling your brain what sounds good...that is the real and exclusively individual truth about each persons preference! Mica has the best advice - listen to as many different basses/tone woods and decide for yourself what your tonal truth is! One mans meat, after all, is another mans poison.
 
The beauty of music is in the ear of the beholder as much as physical beauty is in the eye - another of mother natures classic designs
 
Happy Xmas (or whatever your preference may be)my friends.
 
John.

[adriaan]

Hi Mica,
 
In another thread you mentioned that the LP filter could be tuned higher, to compensate for a less bright sounding top wood. Judging by your comments about koa on this thread, I think that could be a sensible modification for my koa Spoiler.
 
Can it be done by simply replacing a component on the cb, or does it require benchtime at the mothership? I sent the harness over for modifications a couple of years ago (a pan pot and a 0/3/6dB Q switch) so it's no longer the stock package.
 
When I tried out a Fatboy on loan from 0vid, I thought it sounded a bit muffled, but I guess the koa may have had something to do with that ...
 
(Message edited by adriaan on December 19, 2008)

[s_wood]

Can I repeat myself?  For me, the biggest barrier to learning about the tone of different basses in a comparative way relates to differences in the strings. Unless the strings are of the same type brand, gauge and age - and they almost never are - it's virtually impossible to know whether the tone differences you hear are a function of the bass or the strings.  In many case, perhaps most, it's the strings.  If you are a roundwound player like me, just think of the huge difference in tone produced by strings that are right out of the package and strings that are a month old!              
 
Adriaan, if you are trying to wrestle more high end out of your koa Spoiler it's true that you are fighting against the inherent tone qualities of koa, which is a wood that is warm rather than bright.  Before you give up, how about slapping a set of Rotosounds or Dean Markley SR2000's on it?
 
(Message edited by s_wood on December 19, 2008)

[adriaan]

Steve, thanks for the string suggestions. I'm pretty happy with the sound of DR LoRiders (steel) for what I do, but the filter knob has to stay open: move it the slightest bit away from the maximum frequency, and it immediately loses nearly all the sparkle.
 
Even with a koa top, there are frequencies further up the spectrum from the cut-off frequency, and it would certainly help if the LP filter wouldn't cut them off quite so drastically.
 
Which leads nicely to another question: what about an LP filter with an adjustable drop-off rate? The current 12dB/octave is probably a big factor in the Q boost, but I'm not sure it's the right 'voicing' for koa.