Say, in a fiddle, there is a bass bar of wood running in the top, inside, just under the foot of the bass strings.
Would such a beast be helpful in bringing out those lost bass tones in a cbg? I have never made even something similar twice in a row, so I can only compare apples to oranges. Maybe you builders with dozens behind you might have some insight.
You need to be a member of Cigar Box Nation to add comments!
I posted yesterday in another group discussion about this exact topic, strange I found it here. Anyways this is what I've noticed. My first five builds, I glued a 1x1 to the inside of the bottom of the box, then inserted a 1/4x2 on top of it, running the length of the box and cut slots...action is lower than usual. The next five builds I cut the slots the "traditional" way but cutting from the top inside of the box and glued directly to the body. On the first five, the body is supported by the bracing as I thought this may reduce neck tension by distributing it through the body and in turn what I have noticed is that the bracing supports extra tone even though it reduces the inside airspace of the box.
This advice of keeping the components of a CBG in proportion with each other makes sense to me at a gut level. After all, the head, neck, and "tail end" of the "stick" are like the transmission medium and when the wave reaches the end of the stick, it is reflected back and this can, at various points along the neck make the signals add together in strength (creating a standing wave) or it can wipe out the signal, or (usually) do something in between -- usually either degrade the signal a bit, or just not be strong as it could be (compare to the points where there are standing waves). In computer/network cabling situations, we need to terminate the cable with resistors that closely match the impedance of the cable to minimize the reflection, as it tends to degrade the basic signal strength (and we basically ignore the signal boosting additive effect that reflections can also give us). With a guitar neck, I don't even know how one would go about terminating them to effectively eliminate the reflection, and for amplification reasons, we may decide that we don't want to. The trick then is to find the right length of the "stick" (head, neck and tailpiece) that will set up a standing wave in the area of our resonator (cigar box) so that it can be experiencing maximal signal strength (vibration) when we pluck a string. But, then with CBGs, we are talking 3, 4, or 6 stings all tuned differently, and our model suddenly gets too complicated for my simple mind to comprehend. Well, I wish I were better versed in physics so I could give you an answer, but perhaps that's what this proportion formula is trying to do. Does this supposition create any more ideas we can discuss?
-Rand.
Zandi Z said:
this is actually a response to Mark aka Junk Box Instruments. i posted it as a blog, but it has not appeared...sooo...
Mark wanted to know more about what i said about proportions... and do i measure or eyeball it ? I do measure, but eye-balling is ok, too.
My basic premises are these:
'the box' is an amplifier.
'the stick', with hardware, is The Machine.
Why Proportions ?
the most efficient way to get the Box and/or Stick to resonate or 'amplify,' is to 'feed' them 'vibrating lengths' to which they might be most sympathetic....
this minimizes the energy needed to 'push' them to getting them to vibrate and to keep them vibrating.
The Box:
the length of the box is my Basic Unit... i generally round that out to an average between the inside length of box and outside length.
my Scale Length is a WHOLE NUMBER multiple of the Basic Unit.
eg: if BU is 8 inches, Scale Lengths would be 1,2,3,4,5,etc, times as long as the box...... 8 inches, 16 inches, 24 inches,32 inches, and 40 inches, etc.
The Stick:
i choose, or calculate a Scale Length...
i divide that Scale Length value by 4 to get a Stick Unit.
eg: 16 inch Scale Length = 4 inch Stick Unit.
Total Stick Length is equal to 6 Stick Units.
1 Stick Unit is headstock.
4 Stick Units from nut to bridge...(Scale Length).
1 Stick Unit from bridge to tail end.
The Result:
Scale Length is both proportional to the Box and proportional to the Stick .
the possibility of resonance is enhanced;
the possibility of dampening is reduced.
.....resonance is the most efficient way to transfer energy.
To Finish:
a person could place the center of the box directly under the bridge.
i prefer to mount the box so that the bridge sits from 2/3 to 3/4 of the way down the length of the box towards the tail....
i use movable bridges...
experimenting is a great part of this adventure...
i measured LOTS of instruments to see what their proportions were... then, i experimented lots.
thanks for asking, Mark...........zandi z.
Zandi Z said:
Amen, Steven. What you said was elegant in its simplicity. i am a novice player and a novice cbg builder. I am, however, in my Golden Years, as 'they' say. To my eyes and ears, what you said was particularly profound...it is very commonly ignored, perhaps because of its very simplicity.
"Look carefully at traditional acoustic instruments that work well. Notice the various dimensions mentioned above in relation to each other. Try to emulate these proportions in the instrument you are building.
It is the relationships of these factors that count, not the exageration of any one of them". thanks for voicing that...zan.
I am on my 2nd guitar and wanted to try and make it louder unplugged and to try and improve the tone quality. I have seen classical guitars with a double top. SSOO I made a frame out of paint stur stick wood and used mono kote to cover it..like a membrane ,I drilled some small holes under the saddle thru the top of the box. i glued two small dowels in the holes so that they would contact the bridge..and attached the membrane box to the dowels on one end and the neck on the other. We will see if it makes it louder..or changes the tone quality.
this is actually a response to Mark aka Junk Box Instruments.
i posted it as a blog, but it has not appeared...sooo...
Mark wanted to know more about what i said about proportions... and do i measure or eyeball it ?
I do measure, but eye-balling is ok, too.
My basic premises are these:
'the box' is an amplifier.
'the stick', with hardware, is The Machine.
Why Proportions ?
the most efficient way to get the Box and/or Stick to resonate or 'amplify,' is to 'feed' them 'vibrating lengths' to which they might be most sympathetic....
this minimizes the energy needed to 'push' them to getting them to vibrate and to keep them vibrating.
The Box:
the length of the box is my Basic Unit... i generally round that out to an average between the inside length of box and outside length.
my Scale Length is a WHOLE NUMBER multiple of the Basic Unit.
eg: if BU is 8 inches, Scale Lengths would be 1,2,3,4,5,etc, times as long as the box...... 8 inches, 16 inches, 24 inches,32 inches, and 40 inches, etc.
The Stick:
i choose, or calculate a Scale Length...
i divide that Scale Length value by 4 to get a Stick Unit.
eg: 16 inch Scale Length = 4 inch Stick Unit.
Total Stick Length is equal to 6 Stick Units.
1 Stick Unit is headstock.
4 Stick Units from nut to bridge...(Scale Length).
1 Stick Unit from bridge to tail end.
The Result:
Scale Length is both proportional to the Box and proportional to the Stick .
the possibility of resonance is enhanced;
the possibility of dampening is reduced.
.....resonance is the most efficient way to transfer energy.
To Finish:
a person could place the center of the box directly under the bridge.
i prefer to mount the box so that the bridge sits from 2/3 to 3/4 of the way down the length of the box towards the tail....
i use movable bridges...
experimenting is a great part of this adventure...
i measured LOTS of instruments to see what their proportions were... then, i experimented lots.
thanks for asking, Mark...........zandi z.
Zandi Z said:
Amen, Steven. What you said was elegant in its simplicity. i am a novice player and a novice cbg builder. I am, however, in my Golden Years, as 'they' say. To my eyes and ears, what you said was particularly profound...it is very commonly ignored, perhaps because of its very simplicity.
"Look carefully at traditional acoustic instruments that work well. Notice the various dimensions mentioned above in relation to each other. Try to emulate these proportions in the instrument you are building.
It is the relationships of these factors that count, not the exageration of any one of them". thanks for voicing that...zan.
Amen, Steven.
What you said was elegant in its simplicity.
i am a novice player and a novice cbg builder. I am, however, in my Golden Years, as 'they' say.
To my eyes and ears, what you said was particularly profound...it is very commonly ignored, perhaps because of its very simplicity.
"Look carefully at traditional acoustic instruments that work well.
Notice the various dimensions mentioned above in relation to each other.
Try to emulate these proportions in the instrument you are building.
It is the relationships of these factors that count, not the exageration of any one of them".
thanks for voicing that...zan.
Very informative. I tried a new (to me) pick up mounting in my recent 3 string. Piezo mounted by cutting a wine cork and sandwiching element between cork, top and back of box. After snooping around in here, I'll be removing that and freeing up the top I tried so hard to keep free in the first place. I think that will make it sound even better un-plugged.
Thanks!
I think in general a really wide bridge just adds mass to the top and damps vibrations. Violins have a really small bridge footprint on the top. Banjos also have a very small bridge foot print. Guitars with tailpieces also have small bridge footprint (except the Telecaster, but that is a special case related to the pick up.)
However if the bridge is glued to the top as in many acoustic and classical guitars, you need a glue patch large enough to prevent the strings from tearing the bridge off the instrument top.
Think of the top of your instrument as the cone of a speaker. You want it to vibrate as freely as possible.
Best Regards,
Steven
Diane said:
Well, thanks! That's very helpful. So how does a really wide bridge affect things? Lately I've got bridges several inches wide and am thinking that is making things louder. However, again, since I have never built the same thing twice, apples to oranges . . .
(My fiddle is coming along, slowly, but coming along . . .)
Well, thanks! That's very helpful. So how does a really wide bridge affect things? Lately I've got bridges several inches wide and am thinking that is making things louder. However, again, since I have never built the same thing twice, apples to oranges . . .
(My fiddle is coming along, slowly, but coming along . . .)
Doc Oakroot is correct is describing the roles of the soundpost and bass bar in a violin or other bowed instrument. You definitely do not want a sound post in a plucked instrument. The soundpost is a fulcrum point around which the bow drives energy into the instrument top. You don't need that in a plucked instrument, and it would only stop vibrations in the top.
Think about energy inputs.
With a bowed instrument like a violin or bass the player can easily control the attack, volume, timber and release of the sound by using the bow. The instrument receives a relatively large, continuous and controllable energy input.
A plucked instrument, like a guitar, banjo or mandolin has a very limited energy input. You can control the attack and initial power of the pluck, but you cannot add additional energy. The energy decays immediately as the pick leaves the string.
A bowed acoustic instrument will always be louder and have more sustain than a plucked acoustic instrument of the same size. Simply based on the method of energy input.
That is why many of you guitar builders are concerned about resonators and electric pickups. You are trying to take that small initial energy input and multiply it.
Regarding thin tops, think about the thickness of a banjo top compared to a guitar top. If you have a guitar and a banjo top of equal size, which is louder? The banjo. Why? The banjo top has less mass to be driven by the energy input. So more of your input energy comes out in sound, and less is lost in moving the mass of the top.
So yes, thin tops are louder. Thin tops are also fragile, so (in a guitar) you have to design a spidery bracing system that allows the top to withstand the static loading of the string tension and the up or down pressure of the bridge, but also offers the least possible resistance to sympathetic vibration with the string. Top thickness and bracing systems are half magic and half science. Here is the place to play.
Volume is also dependant on the internal volume of the box. Bigger is better up to the point at which the available energy input is overwhelmed by the mass of air you are trying to move. At that point the sound just gets lost somewhere inside the box.
Volume is also dependant on the relation of internal volume to the area of the opening. The vibrating top pumps the air in and out of the sound hole, energizing the air that strikes your ear. If the sound hole is too small, the energy never gets out of the box. If the sound hole is too large, the energy is not focused, and is dissapated.
Bass vibrations have longer wavelength than treble ones. They need a bigger top surface and larger internal volume to propagate. Because Cigar Boxes are by nature smaller than ordinary acoustic guitars, you will never achieve the bassiness in a CB that you can get in a standard instrument.
How to use this information in a CB context?
Look carefully at traditional acoustic instruments that work well. Notice the various dimensions mentioned above in relation to each other. Try to emulate these proportions in the instrument you are building. It is the relationships of these factors that count, not the exageration of any one of them.
For a plucked instrument, start with a relatively large box that has a thin, solid wood top with no paper on it. And go from there.
Hope this helps, Best Regards, Steven (CarolinaFiddle)
When you put in your bridge post, do you center it up under the bridge or stick in under the treble foot/end like a violin? I didn't know posts were a matter of course for some builders.
steve (Roots) said:
I like that design so if u need to put a bridge post under bridge for bracing u can come off of that. Also on the bolt on design u can shim under bolts if u want your neck to angle down. That will help in string clearance. I dont know if this design is better than any but it's good to experiment.
Replies
-Rand.
Zandi Z said:
i posted it as a blog, but it has not appeared...sooo...
Mark wanted to know more about what i said about proportions... and do i measure or eyeball it ?
I do measure, but eye-balling is ok, too.
My basic premises are these:
'the box' is an amplifier.
'the stick', with hardware, is The Machine.
Why Proportions ?
the most efficient way to get the Box and/or Stick to resonate or 'amplify,' is to 'feed' them 'vibrating lengths' to which they might be most sympathetic....
this minimizes the energy needed to 'push' them to getting them to vibrate and to keep them vibrating.
The Box:
the length of the box is my Basic Unit... i generally round that out to an average between the inside length of box and outside length.
my Scale Length is a WHOLE NUMBER multiple of the Basic Unit.
eg: if BU is 8 inches, Scale Lengths would be 1,2,3,4,5,etc, times as long as the box...... 8 inches, 16 inches, 24 inches,32 inches, and 40 inches, etc.
The Stick:
i choose, or calculate a Scale Length...
i divide that Scale Length value by 4 to get a Stick Unit.
eg: 16 inch Scale Length = 4 inch Stick Unit.
Total Stick Length is equal to 6 Stick Units.
1 Stick Unit is headstock.
4 Stick Units from nut to bridge...(Scale Length).
1 Stick Unit from bridge to tail end.
The Result:
Scale Length is both proportional to the Box and proportional to the Stick .
the possibility of resonance is enhanced;
the possibility of dampening is reduced.
.....resonance is the most efficient way to transfer energy.
To Finish:
a person could place the center of the box directly under the bridge.
i prefer to mount the box so that the bridge sits from 2/3 to 3/4 of the way down the length of the box towards the tail....
i use movable bridges...
experimenting is a great part of this adventure...
i measured LOTS of instruments to see what their proportions were... then, i experimented lots.
thanks for asking, Mark...........zandi z.
Zandi Z said:
What you said was elegant in its simplicity.
i am a novice player and a novice cbg builder. I am, however, in my Golden Years, as 'they' say.
To my eyes and ears, what you said was particularly profound...it is very commonly ignored, perhaps because of its very simplicity.
"Look carefully at traditional acoustic instruments that work well.
Notice the various dimensions mentioned above in relation to each other.
Try to emulate these proportions in the instrument you are building.
It is the relationships of these factors that count, not the exageration of any one of them".
thanks for voicing that...zan.
Thanks!
However if the bridge is glued to the top as in many acoustic and classical guitars, you need a glue patch large enough to prevent the strings from tearing the bridge off the instrument top.
Think of the top of your instrument as the cone of a speaker. You want it to vibrate as freely as possible.
Best Regards,
Steven
Diane said:
(My fiddle is coming along, slowly, but coming along . . .)
Think about energy inputs.
With a bowed instrument like a violin or bass the player can easily control the attack, volume, timber and release of the sound by using the bow. The instrument receives a relatively large, continuous and controllable energy input.
A plucked instrument, like a guitar, banjo or mandolin has a very limited energy input. You can control the attack and initial power of the pluck, but you cannot add additional energy. The energy decays immediately as the pick leaves the string.
A bowed acoustic instrument will always be louder and have more sustain than a plucked acoustic instrument of the same size. Simply based on the method of energy input.
That is why many of you guitar builders are concerned about resonators and electric pickups. You are trying to take that small initial energy input and multiply it.
Regarding thin tops, think about the thickness of a banjo top compared to a guitar top. If you have a guitar and a banjo top of equal size, which is louder? The banjo. Why? The banjo top has less mass to be driven by the energy input. So more of your input energy comes out in sound, and less is lost in moving the mass of the top.
So yes, thin tops are louder. Thin tops are also fragile, so (in a guitar) you have to design a spidery bracing system that allows the top to withstand the static loading of the string tension and the up or down pressure of the bridge, but also offers the least possible resistance to sympathetic vibration with the string. Top thickness and bracing systems are half magic and half science. Here is the place to play.
Volume is also dependant on the internal volume of the box. Bigger is better up to the point at which the available energy input is overwhelmed by the mass of air you are trying to move. At that point the sound just gets lost somewhere inside the box.
Volume is also dependant on the relation of internal volume to the area of the opening. The vibrating top pumps the air in and out of the sound hole, energizing the air that strikes your ear. If the sound hole is too small, the energy never gets out of the box. If the sound hole is too large, the energy is not focused, and is dissapated.
Bass vibrations have longer wavelength than treble ones. They need a bigger top surface and larger internal volume to propagate. Because Cigar Boxes are by nature smaller than ordinary acoustic guitars, you will never achieve the bassiness in a CB that you can get in a standard instrument.
How to use this information in a CB context?
Look carefully at traditional acoustic instruments that work well. Notice the various dimensions mentioned above in relation to each other. Try to emulate these proportions in the instrument you are building. It is the relationships of these factors that count, not the exageration of any one of them.
For a plucked instrument, start with a relatively large box that has a thin, solid wood top with no paper on it. And go from there.
Hope this helps, Best Regards, Steven (CarolinaFiddle)
steve (Roots) said:
-
1
-
2
of 2 Next