Varnishing *INSIDE* Guitar?
George Kaschner
Gervais Currie (Ger...@intlog.demon.co.uk) wrote:
: My current guitar (70's Yamaha FG140) has, somewhere along the line,
: been given a coat of varnish *inside*.
:
: Talking to various people, opinions are divided - some say it does
: wonders for projection, tone etc - others say it *can* ruin a guitar.
:
: The Yamaha sounds fine - but of course I cannot compare it to its
: original, unvarnished state.
The line that I was given at the time I first saw such a guitar was that
the interior coating was used to suppress the natural tendency for bare
wood to absorb moisture during shipping from Japan to the U.S. Whether
that was ever a real problem or if this was a fix for a problem that never
existed, I am not sure. I'd like to believe that it has little
detrimental effect on the tone. If it was proven to do wonders in favor
of tone, I'm confident that more people would be using it.
Cheers,
George Kaschner
Daniel M. Amitin
ez00...@bullwinkle.ucdavis.edu (George Kaschner) wrote:
>: Talking to various people, opinions are divided - some say it does
>: wonders for projection, tone etc - others say it *can* ruin a guitar.
>:
>: The Yamaha sounds fine - but of course I cannot compare it to its
>: original, unvarnished state.
>The line that I was given at the time I first saw such a guitar was that
>the interior coating was used to suppress the natural tendency for bare
>wood to absorb moisture during shipping from Japan to the U.S. Whether
>that was ever a real problem or if this was a fix for a problem that never
>existed, I am not sure. I'd like to believe that it has little
>detrimental effect on the tone. If it was proven to do wonders in favor
>of tone, I'm confident that more people would be using it.
Look at it this way, the varnish or finish (inside or out) does effect
your tone, more important in reduces the overall volume you can
achieve with the guitar. If you have a finished guitar the only place
sound will escape is from the sound hole itself, if unfished sound
will vibrate out through the wood.
http://www.ionet.net/~warpath/index.shtml
Michael P. Burns
Linking this thread with the one about smelling the inside of
one's guitar...I wonder if maybe plywood guitars are varnished
inside to block the yucky smell that emmanates from some types
of plywood. Maybe it's from old hide glues but sometimes plywood
can smell pretty bad, especially when it absorbs moisture.
Randy Knott
George Kaschner wrote:
>
> Gervais Currie (Ger...@intlog.demon.co.uk) wrote:
>
> : My current guitar (70's Yamaha FG140) has, somewhere along the line,
> : been given a coat of varnish *inside*.
> :
> : wonders for projection, tone etc - others say it *can* ruin a guitar.
> :
> : The Yamaha sounds fine - but of course I cannot compare it to its
> : original, unvarnished state.
>
> The line that I was given at the time I first saw such a guitar was that
> the interior coating was used to suppress the natural tendency for bare
> wood to absorb moisture during shipping from Japan to the U.S. Whether
> that was ever a real problem or if this was a fix for a problem that never
> existed, I am not sure. I'd like to believe that it has little
> detrimental effect on the tone. If it was proven to do wonders in favor
> of tone, I'm confident that more people would be using it.
>
> George Kaschner
I've read that some manufacturers have finished the inside back and
sides of their guitars to keep shrinking and swelling from humidity
to a minimum. Doing so to the back and sides would not make as big
a difference in tone as finishing the inside of the top would. I would
venture to say that such a coating could improve the volume and tone of
some plywood guitars, particularly those that are made with rather soft
wood.
Clint
George Kaschner
Daniel M. Amitin (war...@ionet.net) wrote:
: ez00...@bullwinkle.ucdavis.edu (George Kaschner) wrote:
:
: >The line that I was given at the time I first saw such a guitar was that
: >the interior coating was used to suppress the natural tendency for bare
: >wood to absorb moisture during shipping from Japan to the U.S. Whether
: >that was ever a real problem or if this was a fix for a problem that never
: >existed, I am not sure. I'd like to believe that it has little
: >detrimental effect on the tone. If it was proven to do wonders in favor
: >of tone, I'm confident that more people would be using it.
: Look at it this way, the varnish or finish (inside or out) does effect
: your tone, more important in reduces the overall volume you can
: achieve with the guitar. If you have a finished guitar the only place
: sound will escape is from the sound hole itself, if unfished sound
: will vibrate out through the wood.
Say what?! So you're saying that an unfinished guitar is going to be
louder because the finish suppresses the vibrations of the top? Maybe if
it was made of urethane of if it was not properly bonded, that could be a
case, but to say that the sound can only escape through the soundhole is,
may I say, mistaken. (I originally wrote "ludicrous" but decided that was
a little strong even if more correct).
You may check you assumption by placing a soundhole cover in your guitar.
I think you'll find that there is still a sound coming from the top. Even
in the middle of a forest with no one else to hear it. ;)
humbly,
george kaschner
Jim Pulling
On Sun, 10 Nov 1996 08:52:42 GMT, war...@ionet.net (Daniel M. Amitin)
wrote:
>If you have a finished guitar the only place
>sound will escape is from the sound hole itself, if unfished sound
>will vibrate out through the wood.
I'd always thought (based on advice early in my guitar playing
adventures) that soundhole is a bit of a misnomer. The main function
of the soundhole (I believed) was to allow air to circulate and the
real sound was generated by the vibrating wood face.
Any comments from the luthiers ??
Regards
Jim Pulling
Daniel M. Amitin
ez00...@boris.ucdavis.edu (George Kaschner) wrote:
>Daniel M. Amitin (war...@ionet.net) wrote:
>: ez00...@bullwinkle.ucdavis.edu (George Kaschner) wrote:
>:
>: >The line that I was given at the time I first saw such a guitar was that
>: >the interior coating was used to suppress the natural tendency for bare
>: >wood to absorb moisture during shipping from Japan to the U.S. Whether
>: >that was ever a real problem or if this was a fix for a problem that never
>: >existed, I am not sure. I'd like to believe that it has little
>: >detrimental effect on the tone. If it was proven to do wonders in favor
>: >of tone, I'm confident that more people would be using it.
>:
>: Look at it this way, the varnish or finish (inside or out) does effect
>: your tone, more important in reduces the overall volume you can
>: achieve with the guitar. If you have a finished guitar the only place
>: sound will escape is from the sound hole itself, if unfished sound
>: will vibrate out through the wood.
>Say what?! So you're saying that an unfinished guitar is going to be
>louder because the finish suppresses the vibrations of the top? Maybe if
>it was made of urethane of if it was not properly bonded, that could be a
>case, but to say that the sound can only escape through the soundhole is,
>may I say, mistaken. (I originally wrote "ludicrous" but decided that was
>a little strong even if more correct).
>You may check you assumption by placing a soundhole cover in your guitar.
>I think you'll find that there is still a sound coming from the top. Even
>in the middle of a forest with no one else to hear it. ;)
Don't misunderstand what I'm saying, if your guitar is unfished the
more vibrations will eminate from the *entire* guitar which in turn
raises the overall volume.
Daniel
http://www.ionet.net/~warpath/index.shtml
Rob Wolf
Jim Pulling wrote:
>
> On Sun, 10 Nov 1996 08:52:42 GMT, war...@ionet.net (Daniel M. Amitin)
> wrote:
>
> >sound will escape is from the sound hole itself, if unfished sound
> >will vibrate out through the wood.
>
> adventures) that soundhole is a bit of a misnomer. The main function
> of the soundhole (I believed) was to allow air to circulate and the
> real sound was generated by the vibrating wood face.
>
> Any comments from the luthiers ??
>
> Regards
> Jim Pulling
I'm not a luthier, but I am an engineer who likes making music.
The sound made by a guitar comes from:
a) The vibrating strings exiting the air
b) The vibrating strings moving the bridge which moves the soundboard
which exites the air.
The vibrating soundboard exites the air on the inside of the guitar and
on the outside. The inside exitation creates waves that bounce around,
kind of like a miniature reverberation chamber. The bouncing waves
affect the exitation of the soundboard (minutely), which can then affect
the exitation of the outside air. But it is the soundhole that lets
these waves out to mingle with the other sounds.
It is the complex mixing of these sources of vibration that creates the
overall tonal quality of a given guitar. This is why everyone gets so
worked up about soundboard woods, body cavity size, body construction,
and string types.
If physics of guitar sounds was simple, maybe there would be a decent
synth program for a clean steel string guitar? ;o) (*no flames please!*)
Rob
--
======================================================================
Rob Wolf Internet: rw...@on.bell.ca
======================================================================
George Kaschner
Daniel M. Amitin (war...@ionet.net) wrote:
: Don't misunderstand what I'm saying, if your guitar is unfished the
: more vibrations will eminate from the *entire* guitar which in turn
: raises the overall volume.
I must not have any fishes in my guitar then 'cause it's loud. ;)
George Kaschner
Charles Tauber
Daniel M. Amitin wrote:
>
> Don't misunderstand what I'm saying, if your guitar is unfished the
> more vibrations will eminate from the *entire* guitar which in turn
> raises the overall volume.
>
> Daniel
>
Daniel,
And, I suppose, your statement is based upon having played a sufficient
number of finished and non-finished guitars and measuring their sound
output. Otherwise your statement would be unfounded arm-chair
speculation which would serve no purpose but to expand the already too
large "mythology" of things having to do with the guitar.
No offence intended, but let's keep it in the realm of reality, shall
we. Or at least state that you we speculating (aka "making it up as we
go along").
Charles
Charles Tauber
Jim Pulling wrote:
>
> On Sun, 10 Nov 1996 08:52:42 GMT, war...@ionet.net (Daniel M. Amitin)
> wrote:
>
> >If you have a finished guitar the only place
> >sound will escape is from the sound hole itself, if unfished sound
> >will vibrate out through the wood.
>
> I'd always thought (based on advice early in my guitar playing
> adventures) that soundhole is a bit of a misnomer. The main function
> of the soundhole (I believed) was to allow air to circulate and the
> real sound was generated by the vibrating wood face.
>
> Any comments from the luthiers ??
>
> Regards
> Jim Pulling
Jim,
That is my understanding, also.
Charles
.
Al Sato
Charles Tauber <tau...@candu.aecl.ca> wrote:
>Jim Pulling wrote:
>>
>> I'd always thought (based on advice early in my guitar playing
>> adventures) that soundhole is a bit of a misnomer. The main function
>> of the soundhole (I believed) was to allow air to circulate and the
>> real sound was generated by the vibrating wood face.
>>
>> Any comments from the luthiers ??
>>
>> Regards
>> Jim Pulling
>Jim,
>That is my understanding, also.
>Charles
Charles,
I suppose this falls in the realm of idle speculation on my part, but
it is a question that has been nagging at me for some number of years
at very low priority. When a loudspeaker designer designs a ported
enclosure for a speaker system, that port can be "tuned" to augment
bass response in a narrow frequency band. Is there any such tuning
possible on a guitar? A big difference between the two might be that
the principal vibrating membrane is the one with the hole on a guitar.
Is the effect not present or is it present but "in the noise" so to
speak?
Thanks.
Al Sato
>.
Craig Reynolds
In article <3289CA...@candu.aecl.ca>, Charles Tauber <tau...@candu.aecl.ca> writes:
|> Daniel M. Amitin wrote:
|> >
|> > Don't misunderstand what I'm saying, if your guitar is unfished the
|> > more vibrations will eminate from the *entire* guitar which in turn
|> > raises the overall volume.
|>
|> number of finished and non-finished guitars and measuring their sound
|> output. Otherwise your statement would be unfounded arm-chair
|> speculation which would serve no purpose but to expand the already too
|> large "mythology" of things having to do with the guitar.
|>
|> No offence intended, but let's keep it in the realm of reality, shall
|> we. Or at least state that you we speculating (aka "making it up as we
|> go along").
Charles,
In the future, please be more careful when reading posts. Daniel
was referring to an "unfished" guitar. Presumably, a guitar that
has no fish inside it will be louder than one chock full o' fish.
Then again, I've never played one. (Or smelled it's soundhole.) :)
With apologies for the non-informative post...
Speculatively yours,
Craig
--
Craig Reynolds, Administrator University of Pennsylvania
GRASP Laboratory Philadelphia, PA 19104
Charles Tauber
Al Sato wrote:
> Charles,
>
> I suppose this falls in the realm of idle speculation on my part, but
> it is a question that has been nagging at me for some number of years
> at very low priority. When a loudspeaker designer designs a ported
> enclosure for a speaker system, that port can be "tuned" to augment
> bass response in a narrow frequency band. Is there any such tuning
> possible on a guitar? A big difference between the two might be that
> the principal vibrating membrane is the one with the hole on a guitar.
> Is the effect not present or is it present but "in the noise" so to
> speak?
>
> Thanks.
>
> Al Sato
>
> >.
Al,
Good question. I don't claim to fully understand the phenomenon, but
the size of the soundhole can, and, by some makers, is varied to affect
the bass/treble balance/response. Smaller soundholes tend to favor
treble response, while larger ones favor bass response. In addition,
the response of the air volume contained within the body is also varied
by some makers to affect the bass/treble balance and response. I
believe that this is refered to as the "0" mode of vibration of the
guitar. Perhaps Gila (Eban) might be able to add to this, being more
knowlegeable that I on this subject.
Charles
Lee Cunningham
Charles Tauber wrote:
>
> Jim Pulling wrote:
> >
> > On Sun, 10 Nov 1996 08:52:42 GMT, war...@ionet.net (Daniel M. Amitin)
> > wrote:
> >
> > >If you have a finished guitar the only place
> > >sound will escape is from the sound hole itself, if unfished sound
> > >will vibrate out through the wood.
> >
> > adventures) that soundhole is a bit of a misnomer. The main function
> > of the soundhole (I believed) was to allow air to circulate and the
> > real sound was generated by the vibrating wood face.
> >
> > Any comments from the luthiers ??
> >
> > Regards
> > Jim Pulling
>
> Jim,
>
> That is my understanding, also.
>
> Charles
>
Hey guys, the body is a "speaker enclosure" and the top is the "cone".
In either case the enclosure acts as an amplifier and "lens" for the
sound coming from the tops vibration. For a demo, find an electric
guitar player with a Pignose amp. Listen as you open and close the
back of the amp.
Now to the topic of varnish ... I don't think varnish inside makes my
ol' faithful '69 Yamaha "humidity-proof", but it may act as a buffer to
slow down the effects of humidity change. I DO think that the old box
has mellowed out over years of use, not remained the same as the day it
was sprayed and shipped. If varnish permanently stabilized the wood, then
most guitars probably wouldn't change much over time, considering the
percentage of finish coverage on most guitars.
-leec
--
-------------------------------------
Name: Lee Cunningham
NYNEX Science & Technology
914-644-2266
le...@nynexst.com
-------------------------------------
david_means
In article <3289EF...@on.bell.ca>, Rob says...
>
>Jim Pulling wrote:
>>
>> On Sun, 10 Nov 1996 08:52:42 GMT, war...@ionet.net (Daniel M. Amitin)
>> wrote:
>>
>> >If you have a finished guitar the only place
>> >sound will escape is from the sound hole itself, if unfished sound
>> >will vibrate out through the wood.
>>
>> I'd always thought (based on advice early in my guitar playing
>> adventures) that soundhole is a bit of a misnomer. The main function
>> of the soundhole (I believed) was to allow air to circulate and the
>> real sound was generated by the vibrating wood face.
>>
>> Any comments from the luthiers ??
>>
>> Regards
>> Jim Pulling
>
>
>The sound made by a guitar comes from:
>
>a) The vibrating strings exiting the air
>b) The vibrating strings moving the bridge which moves the soundboard
>which exites the air.
>
>The vibrating soundboard exites the air on the inside of the guitar and
>on the outside. The inside exitation creates waves that bounce around,
>kind of like a miniature reverberation chamber. The bouncing waves
>affect the exitation of the soundboard (minutely), which can then affect
>the exitation of the outside air. But it is the soundhole that lets
>these waves out to mingle with the other sounds.
>
>It is the complex mixing of these sources of vibration that creates the
>overall tonal quality of a given guitar. This is why everyone gets so
>worked up about soundboard woods, body cavity size, body construction,
>and string types.
>
>If physics of guitar sounds was simple, maybe there would be a decent
>synth program for a clean steel string guitar? ;o) (*no flames please!*)
>
>Rob
Rob,
I'm not really a luthier either, but I play one on TV.
Seriously, though, I too am an engineer who loves making music and who
has some experience in acoustics. While I think your description is
fairly accurate up to the point of discussing the function of the
soundhole, there I believe you may be overlooking the primary effect.
Acoustically, the soundhole functions much like the port on a ported,
or bass reflex, loudspeaker enclosure. The size of the soundhole, in
correlation with the size of the volume of air inside the guitar,
principally determines the air resonance frequency of the guitar. At
this air resonance frequency, the pressure wave generated by the BACK
of the soundboard exits the soundhole IN PHASE with the wave generated
directly by the FRONT of the soundboard, reinforcing its strength.
A clever guitar designer can adjust the air resonance frequency (by
adjusting the size of the soundhole relative to the air volume) to
boost the guitar's total sound output at low frequencies where the
output generated directly by the front of the soundboard is beginning
to fall off, extending bass response without creating a peak in the
response (a boomy bass).
This is my take on it. If I'm too far off the mark, will some REAL
guitar acoustician like Al Carruth please correct me!
Dave Means
dme...@fcc.gov
Doug French
Al Sato (n...@centtech.com) wrote:
: Charles Tauber <tau...@candu.aecl.ca> wrote:
: >Jim Pulling wrote:
: >> I'd always thought (based on advice early in my guitar playing
: >> adventures) that soundhole is a bit of a misnomer. The main function
: >> of the soundhole (I believed) was to allow air to circulate and the
: >> real sound was generated by the vibrating wood face.
: >>
: >> Jim Pulling
: >Jim,
: >That is my understanding, also.
: >Charles
: Charles,
: I suppose this falls in the realm of idle speculation on my part, but
: it is a question that has been nagging at me for some number of years
: at very low priority. When a loudspeaker designer designs a ported
: enclosure for a speaker system, that port can be "tuned" to augment
: bass response in a narrow frequency band. Is there any such tuning
: possible on a guitar?
I suspect that the main advantage to a guitar with a sound hole vs.
on without it is in the reduced "stiffness" of the system with the
hole. There is a parallel between the ported speaker boxes you
mentioned and 'closed-box' speaker systems. The closed box system
is 'stiffer' and generally requires more power to produce the same
acoustic loudness that is produced from an equivalent 'ported' system.
Since the amount of power that can be transfered from the strings
to the soundboard is generally limited by the strengths of the materials
of the guitar the open soundhole is the more efficient and desirable
design. You are correct that the ports on ported speakers are "tuned"
to the particular speaker/box combination. Ports can add better than
a half octave of acceptable bass response to a well designed speaker.
: A big difference between the two might be that
: the principal vibrating membrane is the one with the hole on a guitar.
: Is the effect not present or is it present but "in the noise" so to
: speak?
IMHO, the soundhole is there both for it's open-box efficiency and
it's bass extending characteristics. The best of both worlds, so
to speak. I'd also guess that it would also be much harder to build
and repair closed face guitars :)
A rough parallel lies in the design of a violin. There is an
internal brace under the bridge between the back and front of the
violin. It's placement is critical to the sound produced by
the instrument as it changes the vibration 'modes' of the instrument.
So I doubt that the effect is "lost in the noise" even in the
simpler design of the guitar.
As for the finish on the inside of the guitar, the original poster
didn't say if the finish was only on the insides of the sides and
back, or if it was also on the inside of the soundboard.
It would seem reasonable that coating both sides of the wood would
slow down the rate of absorption of moisture from the surounding air
as well as equalize the rate of expansion of the two faces of each
piece of wood. Wouldn't this (in theory) reduce the stresses that
a guitar undergoes as it expands and contracts with changing
conditions? As to finishing the inside face of the soundboard,
perhaps the increased stiffness of the face could be offset by
careful and skillful redesign of the soundboard and the bracing.
But that is the domain of a luthier, not this humble electrical
engineer.
paul...@erinet.com
In article <56fqcu$i...@lana.zippo.com> David Means writes:
>From: David Means
>Subject: Re: Varnishing *INSIDE* Guitar?
>I'm not really a luthier either, but I play one on TV.
>Seriously, though, I too am an engineer who loves making music and who
>has some experience in acoustics. While I think your description is
>fairly accurate up to the point of discussing the function of the
>soundhole, there I believe you may be overlooking the primary effect.
>Acoustically, the soundhole functions much like the port on a ported,
>or bass reflex, loudspeaker enclosure. The size of the soundhole, in
>correlation with the size of the volume of air inside the guitar,
>principally determines the air resonance frequency of the guitar. At
>this air resonance frequency, the pressure wave generated by the BACK
>of the soundboard exits the soundhole IN PHASE with the wave generated
>directly by the FRONT of the soundboard, reinforcing its strength.
>A clever guitar designer can adjust the air resonance frequency (by
>adjusting the size of the soundhole relative to the air volume) to
>boost the guitar's total sound output at low frequencies where the
>output generated directly by the front of the soundboard is beginning
>to fall off, extending bass response without creating a peak in the
>response (a boomy bass).
>This is my take on it. If I'm too far off the mark, will some REAL
>guitar acoustician like Al Carruth please correct me!
>Dave Means
>dme...@fcc.gov
I thought that "porting" speakers only really did any good if for all other
intents and purposes, the speaker was an "infinite" baffle, that is, solid
enough (.75" plywood or whatever) to keep vibrations from straying out the
front, back and sides. For that reason, the "ports" on boom boxes and cheap
bedroom plastic stereos are for show, and serve no real purpose. Usually
people port speakers to lower the "resonant frequency" from, say 90hz to 50hz.
But a 90hz wave is not likely to get "trapped" inside a wood enclosure less
than an eight of an inch thick, unless I've got MY physics all screwed up. So
the "porting" function, if it is effective at all, would only be effective
down to the lowest frequency that the guitar's construction otherwise
restricts from coming out the back and sides, which would be, what, 200hz or
higher?
Just pooling my ignorance here. :-)
Chuck DeHart
In article <563u15$f...@ionews.ionet.net>, war...@ionet.net says...
>
>ez00...@bullwinkle.ucdavis.edu (George Kaschner) wrote:
>
>
>>: Talking to various people, opinions are divided - some say it does
>>: wonders for projection, tone etc - others say it *can* ruin a guitar.
>>:
>>: The Yamaha sounds fine - but of course I cannot compare it to its
>>: original, unvarnished state.
>
>>the interior coating was used to suppress the natural tendency for bare
>>wood to absorb moisture during shipping from Japan to the U.S. Whether
>>that was ever a real problem or if this was a fix for a problem that never
>>existed, I am not sure. I'd like to believe that it has little
>>detrimental effect on the tone. If it was proven to do wonders in favor
>>of tone, I'm confident that more people would be using it.
>
>Look at it this way, the varnish or finish (inside or out) does effect
>your tone, more important in reduces the overall volume you can
>sound will escape is from the sound hole itself, if unfished sound
>will vibrate out through the wood.
>
>
>http://www.ionet.net/~warpath/index.shtml
>
Daniel,
I am curious about your statement that the overall volume would be reduced.
How have you come to know or believe this?
Otherwise, I have to agree with George that, if an interior finish somehow
added to the sound, it would probably be a standard practice by now. I make
sure that all interior surfaces are sanded/burnished to the backside of 600
grit sandpaper, and shellac only the back braces.
Thanks,
Chuck
David Bucher
As regards the idea of sealing or finishing the insides of guitars, I believe
that its a blend of fashion and tradition nothing eles. Many older
instruments have finish and even parchment, linen and gutta percha and
other coatings inside. Ervin Somogyi finishes (lightly!) the insides of his
guitars. It does indeed make it easier to clean the inevitable dust that
collects inside of the box. I tried finishing the insided of a few of my
guitats but people don't seem to like it. Its not what they expect or are
used to seeing so I no longer do it! I solved the problem of dust by
rubbing to a finer polish, the insides (plates, braces, patches etc) so
they're smooth to the touch. This also inproves the craftsmanship of the
instrument as a whole, a practice I STRONGLY recommend for all!
As far as sound is concerned, the top might br muffled somewhat by a
thick interior finish but a thin seal coat will do NOTHING to the sound.
The back and sides are (here we go again) mostly a framework of support
for the membrane of the top. And as for the idea that "sound comes out
of the wood"...well, what can one say to that? Just ask Steve Klien about
soundholes! (ask me too!).
David Bucher, luthier
http://www.mcn.org/b/goldenwood/
David Bucher email: dbu...@mcn.org
The Golden Wood Stringed musical Instruments Aero-Pac# 11
33700 S.Hwy.One Tripoli# 829
Gualala, CA 95445 Eye of the Storm Rocketry
Ph. 707 884 4213
Lothlorien Orpheus Caras Galadon
mez...@pacbell.net
> : >Jim Pulling wrote:
>
> : >> I'd always thought (based on advice early in my guitar playing
> : >> adventures) that soundhole is a bit of a misnomer. The main function
> : >> of the soundhole (I believed) was to allow air to circulate and the
> : >> real sound was generated by the vibrating wood face.
> : >>
> : >> Jim Pulling
If there was no soundhole, no sound would get out and you'd have a silent
guitar. Then if you made a soundhole later, all the stored up sound would
come flying out at one time. Better off putting a soundhole in, in the
first place, Mez thinks.
Mezzoro
Of course, if you didn't have a soundhole, you wouldn't lose picks in
there. There must be a hundred picks lost inside my guitar.
david_means
In article <paulrace.9...@erinet.com>, paul...@erinet.com says...
>higher?
>
>Just pooling my ignorance here. :-)
>
Hi, Paul,
Well, we may indeed be pooling ignorance, but that can be a lot of fun, too!
Two points: first, let's get the terminology straight. I've built a few
ported speaker enclosures in my time, so here's my understanding... an
infinite baffle is simply a sealed enclosure that is big enough that the
compression of the air inside from the movement of the speaker cone (or in
this case the guitar soundboard) is insignificant in its effect on the
movement of the cone (or soundboard). That is, the compliance of the cone
(or soundboard) is not changed by any "air spring" effect from the
compression of the air behind it. The infinite baffle totally isolates
the front wave from the back wave of the radiator (cone or soundboard),
which is good from the standpoint of smooth frequency response, but does
nothing to prop up the "bottom end" which will fall off below the free air
resonant frequency of the radiator.
An acoustic suspension enclosure, on the other hand, uses a sealed enclosure
that is small enough to allow the trapped air to act as an "air spring" to
stiffen the compliance of the radiator (cone or soundboard) and raise its
resonant frequency. This would probably have little or no utility in the
guitar analogy, except possibly to tame an overly floppy soundboard!
The ported enclosure, which I believe the acoustic guitar really is,
functions as I described in my first post. And I think it is pretty neat
that luthiers discovered the benefits of porting hundreds of years before
loudspeaker designers did. Even though stringed instruments had sound-
holes for centuries before the loudspeaker was invented, it still took
twenty or thirty years for loudspeaker designers to catch on to the
benefits!
My second point regards your comments about the enclosure thickness. Here
is where the guitar and loudspeaker models diverge significantly. Whereas
it is the function of a loudspeaker and its enclosure to REPRODUCE an
acoustical representation of an electrical waveform as accurately and
colorlessly as possible, a guitar is tasked with PRODUCING an interesting
and highly colored acoustical waveform. This is why the ideal material
for a loudspeaker enclosure (except for considerations of portability!)
is something like concrete, the thicker the better -- totally rigid,
inert, and free from resonances. This is also why you want something that
is full of interesting resonances for guitar sides and backs -- you want
to create a colorful, complex sound that is full of harmonious overtones --
and thin hardwood fits the bill. It is not a matter of sound leakage --
on a guitar you want all of the plates to be vibrating in interesting ways.
The frequencies you are tossing around (90 and 50 Hz) may be typical of
free air resonance and low-frequency cutoff frequencies of small ported
speaker systems, but the natural resonance of a guitar soundboard is on
the order of a few hundred Hertz. According to Abe Cohen's old tome
on enclosure design, the "propping up" effect of a properly tuned port
extends about one octave below the free air resonant frequency. I guess
that makes getting sufficient levels of the fundamental from the low
E string (83 Hz) sort of a "brute force" affair.
Of course there is a lot more to guitar acoustics than just port tuning
effects. Designing for optimal low-frequency port reinforcing benefits
may well screw up high frequency response. This is still very much a
black art.
Sorry for the long, looooong post, but these things don't lend themselves
to succinct discussions. I find it fascinating that something so
outwardly simple as a guitar can be so damned complex when you study it
closely. I hope others who have studied this will chime in and feel free
to tell me that I'm full of hot air if they've got some sound analysis to
back themselves up!
MHO,
Dave Means
dme...@fcc.gov
David Bucher
>If there was no soundhole, no sound would get out and you'd have a silent
>guitar. Then if you made a soundhole later, all the stored up sound would
>come flying out at one time. Better off putting a soundhole in, in the
>first place, Mez thinks.
>Mezzoro
>Of course, if you didn't have a soundhole, you wouldn't lose picks in
>there. There must be a hundred picks lost inside my guitar.
>
About ten years ago I made an experimtntal guitar for a client who just couldn't decide how the soundhole would be decorated and whe=
re to put it. So I told him that I could leave quite a bit of room among the braces for a soundhole that could be placed, sometime=
in the future, more or less where he wanted it. I finished the guitar and strung it up and delivered it to the client with the sug=
gestion that he set it on a stand down the hall where it could be viewed from all angles and be picked up and played for purposes of=
inspiration. Maybe in a couple of months a design and placement might come to him. =
Well, sure enough in
three weeks I got a call from him saying that he had arrived at a descision and could I come over and pick the guitar up? When I go=
t there I could tell that the guitar had been played a lot even though you couldn't hear much when you strummed, but the scratch ma=
rks on the top showed considerable picking had taken place. He'd taped to the top a 4.75 " ellipse with the decoration penciled in =
and said that this was the shape and place where the soundhole should go. "Can you do this? he asked. "Sure, I said. I'll just ma=
ke a template for the trimmer and buzz it out"
I left with the guitar and, arriving back at my shop, I quickly generated an elipse on my computer, made the templates for the =
variuos sizes I needed and, after first removing the strings, clamped the guide on the guitar and flipped on the trimmer. First I b=
uzzed out the channels for the rosette being carfull to pencil some regestration marks on to the top for proper placement the soundh=
ole template. I then removed the rosette pattern and clamped down the soundhole pattern.
It was then that I noticed the pecular buldging of the top as though I'd built a pretty high arch into it. Althoiugh I do arch t=
ops slightly, I DID NOT put this much curve into it! I thought maybe the deformation might be a result of string tension but knew t=
hat this could not be in only three weeks. Besides, the deformation I was seeing was all wrong for this type of problem. Curious, =
I determined that I would put the mirror into that baby just as soon as I got that hole punched through! Flipping the switch on the=
trimmer, I began to drop the bit into the wood of the top. The bit began to cut when...the whole guitar exploded on my bench with =
an increadibly loud bang sending a shower of small wood fragments and slivers everywhere. Several pieces stuck, like shrapnal, in m=
y face while other pieces were lodged in my sweatshirt and shop apron. The neck flew into my paint shelf knocking several gallons o=
f laquer to the floor, there to splash all over everything within range. The bridge shot up , glanced off of the shop cieling and b=
ounced off my sander and then into the coils of fretwire hanging on the wall, sending them clattering to the floor to bounce wildly =
about like springs!
When the dust settled, all that was left was the back with several sections of side still attached. I thought to myself "that g=
uy! He must have set me up by getting some kind of bomb inside the guitar. But when I examined the wreakage closely it became clea=
r that no flame or fire was involved. There were no scorch marks or burns. There was no smell of fuel or chemicals as one would ex=
pect with a bomb. After much thought and carefull consideration, I determined that it was that pesky 'ole sonic energy stored up w=
ithoiut relief for more than three weeks to be suddenly released when I punched the bit into the top.
Let that be a lession to you all. Don't ever play a guitar without a soundhole, NOT!!!
Chuck DeHart
In article <328bcb9f...@158.43.128.9>, jim.p...@dial.pipex.com says...
>>sound will escape is from the sound hole itself, if unfished sound
>>will vibrate out through the wood.
>
>adventures) that soundhole is a bit of a misnomer. The main function
>of the soundhole (I believed) was to allow air to circulate and the
>real sound was generated by the vibrating wood face.
>
>
>Regards
>Jim Pulling
Jim,
That last question is the kind that really opens up this stuff.
Re: Soundhole funtion:
I will try to delineate my experience from training from speculation. Preface
here that speculation rules my vision of the way a guitar sounds. Read to the
bottom to find out why. Ask me the same question in 20 years and I may have a
different response. Hope others will comment:
Experience: Tap the bridge of your guitar with no strings on while holding your
hand over the soundhole and you should feel air moving.
Speculation: The same thing happens when you pluck a string (hard to get your
hand close in there at the same time the string are on and there is a differenc
in amplitude that may make it harder to feel the air move.) Now imagine
blowing smoke rings out of your soundhole. Are they perfect rings or wobbly and
ill formed?
Training: A wider diameter soundhole creates more treble. Smaller will make
more bass response. (I think I read this somewhere once also).
Speculation: Soundwaves eminate from both the inside and outside of the top
(The top has two faces). Also from the edge of the soundhole.
Speculation: The larger lower bout acts to compress air into the smaller upper
bout, giving the signal eminating from the area of the soundhole a boost to
help project the sound. Probably also helps project whatever vibrations bounce
around the interior of the instrument. (The only other reason I can think of
having a smaller bout is to help get a "corrugated" effect into the design to
help make the instrument stronger for a give amount of wood.)
Speculation: Putting a heavy finish on the inside of the top may reduce volume
by "weighing" down the top/ restricting its vibration. Otherwise, a heavy
finish probably does more to change the tone of the instrument; changing it to
sound more like vibrations bouncing off a finishing product and less like the
vibrations of a unique assembly of finely selected woods.
So, the next instrument I build will be designed with the following concepts
unless somebody can convince me it shouldn't be: Design your soundhole with a
reinforcement (and for the rosette) that helps "blow smoke rings"; that does
not wobble. I cut a spruce circle slightly wider than the rosette and glue it
with the grain running perpendicular to the grain in the top. Sand everything
inside to the backside of 600 grit sandpaper so dirt and moisture have less
surface area to accumulate. Shellac spruce back brace to help them stay more
stable and, maybe, reflect sound better (than softer unfinished spruce).
Much of the design of a guitar results from people who experimented over many
many years. That which pleases the ear, tends to be replicated. One can think
about the guitar as a product of engineering and try to isolate all the
variables and predict sound. Or, one can examine the historical form, replicate
and experiment. My intuition, based upon concepts like those listed above,
tells me not to put a heavy finish on the inside of my guitar.
Anybody ever built or heard a guitar without a smaller upper bout?
Anybody read this far?
Later,
Chuck
Mark Blanchard
In article <56qf1h$4...@s10.mcn.org>, David Bucher <dbu...@mcn.org> wrote:
After much thought and carefull consideration, I determined that it was
that pesky 'ole sonic energy stored up w=
> ithoiut relief for more than three weeks to be suddenly released when I
punched the bit into the top.
> Let that be a lession to you all. Don't ever play a guitar without a
soundhole, NOT!!!
Wow!! great story. That's the kind of thing repairmen have nightmares about.
I'm not sure I believe the "sonic energy" theory though. It sounds to me
like the guitar was pressurized, perhaps by being assembled at much higher
atmospheric pressure than on the day it exploded. Or maybe it was much
warmer that day, or both.
I hope this sort of thing never happens to me!!
--
Mark Blanchard
Mammoth Lakes, CA
Charles Tauber
Chuck DeHart wrote:
>
> Re: Soundhole funtion:
>
> Training: A wider diameter soundhole creates more treble. Smaller will make
> more bass response. (I think I read this somewhere once also).
>
Interesting, my experience suggests the opposite.
Shellac spruce back brace to help them stay more
> stable and, maybe, reflect sound better (than softer unfinished spruce).
>
For reasons I've not tried to explain, I find mahogany consistently
sounds better for back braces, at least for what I'm doing. An old
Ramirez guitar that is in for repair has Spanish Cedar back braces.
I'll probably try that next.
>
> Anybody ever built or heard a guitar without a smaller upper bout?
No, but prior to Torres, guitars had nearly equal sized upper and lower
bouts. One of the improvements in guitar design attributed to Torres
was the increasing of the size of the lower bout.
> Anybody read this far?
Yes.
>
> Later,
> Chuck
gegu...@aol.com
Hi! I was cruising by and saw my name mentioned in a November 14 posting,
so here I am, stopping in for a while. But there's not much I can add
since everybody made so many good points especially about soundholes! Of
course David Bucher's exploding guitar really ought to be checked with a
Geiger counter -- sounds like some kind of spontaneous fission... with
"critical tension" maybe playing the role of "critical mass." Or maybe it
was neutron bomb, since David says there were no signs of fire-damage
etc...
Well here are some sources I've been learning from: Two of the key people
who did research on guitars' low-order vibration-modes including the
so-called "air mode" are Thomas Rossing (from Illinois) and Graham
Caldersmith from Australia. Rossing's written two textbooks: "Science of
Sound" (1982) published by Addison Wesley in 1982 (now in its second
edition) and together with N. Fletcher, "Physics of Musical Instruments"
published in 1991 by Springer-Verlag, I think it now has a soft-cover
edition.
The good point about the books is that they are likely to be readily
available in a nearby library. Rossing also wrote a paper titled "Sound
Radiation from Guitars," in a GAL publication, American Lutherie #16
(Winter 1988). Here's a quote that'll address one of the points that came
up here:
"
"At low frequency, the top plate transmits energy to the back mechanically
via the the ribs, and acoustically via the air enclosed in the body. Sound
is radiated by the top plate, the back plate, and by the soundhole.
Although this is also true at high frequency, the contributions from the
back and soundhole are relatively unimportant compared to the multipole
radiation by the top plater itself. At high frequency we have to consider
the frequency response of the bridge, which acts as a mechanical filter."
Graham wrote a few articles for thhe Catgut Acoustical Society Newsletter
(now called CAS Journal). In "Plate Fundamental Coupling and its Musical
Importance" he writes that
"It has been shown that the air and main wood modes are not independent
modes of vibration but are in fact a resonance-doublet, caused by the
coupling of the air pistons in the soundhole to the fundamental mode of
the top plate via the elastic air volume enclosed in the instrument body."
Graham also wrote a wonderful paper called "Dissolving the mysteries," in
one of the old GAL Quartelies (Vol. 10 #4, 1982). Here he says that
"The fundamental mode of vibration of the guitar face (meaning top) is
coupled to the air-piston in the soundhole through the elastic air volume.
At the air resonance, the air piston is blown out by the face moving in
during cycles of vibration, but it overshoots, producing a net volume
flow. At the main wood resonance the face and air piston move in and out
together.
The GAL item is out of print, but you can read Graham's "Radiation from
Lower Guitar Modes" in American Lutherie #2 (June 1985). He also has two
papers in the Journal of Guitar Acoustics, which Tim White re-issued
recently. Tim isn't hard to find, try e-mailinh tp...@aol.com.
Ok but what does all of this MEAN? Well, the guitar's soundbox-plus
soundhole acts in part like a coke or wine bottle, where you can produce a
nice note by blowing across the bottle's opening. It's basically a
Helmholtz resonator, where the the air "at" the opening and the air
inside the "cavity" form a vibrating system that is analogous to a
mass-and-spring system. If you increase the air-volume, all else
unchanged, the note's frequency will go down. Of course you can make it go
up by filling the bottle with a liquid (or fish.. :-) :-).) Redusing the
size of the opening (as you would if you partially blocked it with a
fish...)tends (in theory) to make the frequency go down, and vice versa.
This is a very rough description, in the papers and textx I mentioned
everything's described much more precisely.
So now you produced you nice note with the bottle. But if you "slapped"
the side of the bottle with your fingers, you'd hear a faint, weak, echo
of that very same note. (Aside: I think I hear a teeny-weeny variation in
pitch, I don't know if I'm imagining this, or if it's the
high-harmonics-content that comes with the slap, anyway it's extremely
small if it's even there at all). Well, how can it be that we "excite"
that vibration when presumably it's just "an air thing?" The reason is
that unlike the theoretical object, the walls are not totally rigid. They
can move, so they move the air enclosed inside, which starts to vibrate
"on its own tems" as it were, i.e at its own natural frequencies. So even
though you get "more bang for the buck" by blowing air across the opening,
you can "access" that "air mode" from the walls. Except now it's not
really an air-mode, it's air-and-walls-mode.
And one should raise the question: If the shape of the resonator is not a
"simple" one (like a sphere with a round opening in it) how do we know
where the "enclosed air-volume" ends and the "piston at the opening"
begins?
Now in a guitar, this happenes to an even greater degree! That's why you
can, say, with holography, see two similarly-shaped modes with one
circular nodal line going around the guitar's lower bout, maybe in some
guitars reaching partlky into the upper bout. It shows the coupling
(energy transfer or "sharing") between the air mode and the top's lowest
mode in which it vibrates in and out or up and down like a trampoline. So
you get "two for the price of one," plus the "air modes" energy at a lower
frequency.
Without this coupling, the modes would be at around (roughly, don't hold
me to it) 160 Hertz. Because of the coupling, we get one at around 85-110
Hz (between low E note and low A note on sixth string) and another at
around 190-210 Hz (notes somewhere on fourth or third string). If you
listen carefully, you can actually HEAR where each one is by playing a
chromatic scale on the guitar.
In many cases, the BACK enters the picture too, so we get three for the
price of one! The former case is called bass-reflex and this is
double-reflex.
There's an article of mine in American Lutherie #8 (Dec, 1986) where you
see this, and you also see how important the ":wall compliance" is,
because it describes an experiment where I took out BOTH top and back
waist-bars. The guitar's body-outline was unchanged. The depth of the
sides varies only minutelky, if at all. The soundhole diameter was
practically unchanged. But many modes, including the presumed air-mode
dropped in frequency, just because of the increased wall-compliance! (Some
modes really took a nose-dive!)
This and other experiences in acoustics labs convinced me that the
distinction between "structural" and "acoustical" parts of the guitar,
especially the top, isn't very useful. Some people call the waist bar
"harmonic bar." I recall one "expert" saying: "What a horrible name! The
bar is purely structural!" Well, this and verious other accounts show
this bar is very very "harmonic."
All this also suggests the following: We tend to think of air-volume and
soundhole diameter as the main things controlling the frequecy of the "air
mode." But practical experience shows that varying the wall-compliance may
be a more effective way of doing so in guitars.
Finally, I want to mention another paper: "Inertance of Guitar Sound Hole"
by Fred Dickens (another person whose papers you ought to read) in Catgut
Acoustical Society Newsletter #29 (May 1978). It talks a lot about the
importance of wall-compliance, but what makes it especially fascinating
for me is the suggestions that OTHER FACTORS BESIDES THAT may be playing a
very important role. One such is the proximity of the back to the
soundhole. Fred concludes that "The exponential-like rise in hole
inertance as H (side-height) is reduced would seem to indicate that under
certain circumstances, say a guitar with stiff sides and large plate
compliance, one could obtain a decrease in the air resonance A0 for a
sufficient reduction in side height."
This starts to point in the direction taken by some postings here: Not
just the air-volume, but the SHAPE of the air-cavity is important.
Now I'm speculatin 9instead of quoting) but all these things may also
explain Charles Tauber's "counter-example" where a smaller sound hole
helped the treble:
Maybe something in the design made the top stifer, or altered its
frequency in a certain way. Maybe something in the structure altered the
configuration of the air-cavity. But finally (that is another topic). Is
he talking about a lowering or raising of mode-frequencies, or a change in
the tone-quality? This is a whole other subject but lower mode-frequencies
do not always mean more bass and/or a warmer sound, and higher ones do not
always mean more treble and/or a crisper tone!
THE PLOT IS THICKENING !
Gila Eban
Al Sato
gegu...@aol.com wrote:
(much good material snipped)
Gila,
Thank you very much for your informative posting. I intend to look up
these references ASAP. A lot of questions along these lines have been
resonating (mode 1 or higher) in my mind for a while. Which is why I
asked Charles about this. He was right to point toward you.
This is not to denigrate any of the other informative postings or the
lovely flame wars ;^) but a pearl like this (no comments about swine,
please!) really makes my day on this newsgroup.
Thanks again.
Al
Giri Iyengar
Chuck DeHart wrote:
> Re: Soundhole funtion:
> Training: A wider diameter soundhole creates more treble. Smaller will make
> more bass response. (I think I read this somewhere once also).
Chuck,
Benedetto's book actually states the opposite. He says that smaller
soundholes will yield a more focused, trebly sound. Do you recall
where you might have read this?
I recently played two almost identical Dupont Macaferri-style guitars.
(Damn, I'm *never* sure of that spelling.) One had the large "D" sound-
hole and the other had the smaller oval one. The guitar with the smaller
soundhole had a distinctly punchier, focused sound. Obviously, there
are differences inherent to *any* two guitars, but I feel quite comfortable
attributing this particular difference to the soundhole design.
On the other hand, a larger vibrating soundboard area seems to be
conducive to a warmer, bassier sound. So a soundhole that increases
the 'active' soundboard area may help emphasize low-end. However, I
think the treble-enhancing effect of a smaller hole outweighs this
effect, at least in this case, and probably in most. Steve Andersen
builds an archtop with an oval soundhole in the upper bass bout. One
of his goals with this design is to increase the sounboard area and
thus make the sound warmer. Seems to work really well for him. Keep
in mind that the soundhole here was about as large as a 'normal' one.
..Giri
Charles Tauber
gegu...@aol.com wrote:
>
>
> Now I'm speculatin 9instead of quoting) but all these things may also
> explain Charles Tauber's "counter-example" where a smaller sound hole
> helped the treble:
> Maybe something in the design made the top stifer, or altered its
> frequency in a certain way. Maybe something in the structure altered the
> configuration of the air-cavity. But finally (that is another topic). Is
> he talking about a lowering or raising of mode-frequencies, or a change in
> the tone-quality? This is a whole other subject but lower mode-frequencies
> do not always mean more bass and/or a warmer sound, and higher ones do not
> always mean more treble and/or a crisper tone!
>
> THE PLOT IS THICKENING !
>
> Gila Eban
Hi Gila,
Thanks for the informative and thorough response.
As far as your speculation on my "counter-example", it could well be
due to any of the things you suggest. In practical terms, on large
steel string acoustic guitars, I find that a smaller soundhole gives a
more "focused" sound with a less "boomy" or "muddy" bass response. I
don't make dreadnaught sized guitars; instead I make small bodied
guitars that are less deep (smaller air volume). Part of my preference
for the sound of small bodied instruments is likely the result of the
smaller air volume. The volume/projection of the small instruments is
not reduced, and is usually as loud or louder than much larger
instruments.
Charles
david_means
In article <19961122055...@ladder01.news.aol.com>, gegu...@aol.com says...
>
<long, but excellent post snipped>
>
>THE PLOT IS THICKENING !
>
>Gila Eban
Great post, Gila!
Good to hear some luthier/scientists weighing in to help dispel some of
the simplistic myths. Maybe now some of the folks who don't give a hoot
about the science behind all this will at least have some realization of
and appreciation for the complexity of the interactions.
Dave Means
dme...@fcc.gov
spe...@usit.net
d
>It would seem reasonable that coating both sides of the wood would
>slow down the rate of absorption of moisture from the surounding air
>as well as equalize the rate of expansion of the two faces of each
>piece of wood. Wouldn't this (in theory) reduce the stresses that
>a guitar undergoes as it expands and contracts with changing
>conditions? As to finishing the inside face of the soundboard,
>perhaps the increased stiffness of the face could be offset by
>careful and skillful redesign of the soundboard and the bracing.
>But that is the domain of a luthier, not this humble electrical
>engineer.
This is what I've done in building boats and repairing houses. I've
coated both sides before construction. I believe Overholtz or some
such name in California used Thompsons Water Seal, a clever idea. Not
where glue would go, of course. Many times I've seen the braces form
ridges on the face; this is excatly the type of deformation I was
reducing in finishing both sides so that the take-up of moisture was
even. Were I to build guitars, I would finish the insides!
Steve
Chuck DeHart
In article <3291BA...@candu.aecl.ca>, tau...@candu.aecl.ca says...
>
>Chuck DeHart wrote:
>>
>> Re: Soundhole funtion:
>
>>
>> Training: A wider diameter soundhole creates more treble. Smaller will make
>> more bass response. (I think I read this somewhere once also).
>>
>
>
Charles,
Thanks for your response. I have been hoping someone would bring up the "E"
(xperience) word for this subject. I imagine a number of dynamics occur with
change in soundhole. Which ones will/may dominate is something to be
experienced.
>
>
> Shellac spruce back brace to help them stay more
>> stable and, maybe, reflect sound better (than softer unfinished spruce).
>>
>
>For reasons I've not tried to explain, I find mahogany consistently
>sounds better for back braces, at least for what I'm doing. An old
>Ramirez guitar that is in for repair has Spanish Cedar back braces.
>I'll probably try that next.
>
>
I was taught to use either mahogony or spruce for the classical and have used
both. Enjoy the Spanish Cedar.
>>
>> Anybody ever built or heard a guitar without a smaller upper bout?
>
>No, but prior to Torres, guitars had nearly equal sized upper and lower
>bouts. One of the improvements in guitar design attributed to Torres
>was the increasing of the size of the lower bout.
>
>> Anybody read this far?
>
>Yes.
>
Thanks again,
Chuck
>>
>> Later,
>> Chuck
David Bucher
spe...@usit.net wrote:
I believe Overholtz or some
>such name in California used Thompsons Water Seal, a clever idea. Not
>where glue would go, of course. Many times I've seen the braces form
>ridges on the face; this is excatly the type of deformation I was
>reducing in finishing both sides so that the take-up of moisture was
>even. Were I to build guitars, I would finish the insides!
>
>Steve
Speakijng of Overholtzer, he was a great guitarmaker with some wild
ideas which I think many luthiers (including me!) use where they might.
If you can find his book, get it! I've got one and he more or less did it him
self in the Leo Fender/Doc Kaufman style but for classic guitars! He
WAS NOT afraid to go against tradition (as I often am!).
Charles Tauber
David Bucher wrote:
>
> Speakijng of Overholtzer, he was a great guitarmaker with some wild
> ideas which I think many luthiers (including me!) use where they might.
> If you can find his book, get it! I've got one and he more or less did it him
> self in the Leo Fender/Doc Kaufman style but for classic guitars! He
> WAS NOT afraid to go against tradition (as I often am!).
>
> David Bucher, luthier
>
David,
Have you ever played an Overholtzer guitar: I've not had the oportunity?
Any comments on the instrument(s) that you played?
If you have not played any of his intruments, one what do you base your
opinion that he was a great guitarmaker? I was relatively unimpressed
with his book and his fixation on aluminum jigs and fixtures. The book is
certainly worth reading, but I don't consider it one of the important,
must-read books on guitar making.
Just my opinion.
Charles