Stone guitars

[PlainSongs]

Saw a video of a guy playing an alabaster flute on Youtube and it turns out this Italian dude makes all manner of instruments, including guitars and drums, in stone (inspired by Etruscan flutes):

http://www.alabastrosonoro.com/index.htm

Check out a collection of all-stone tunes of various styles at

http://www.alabastrosonoro.com/audio.html

Not sure you can hear it's stone -- nice though.

Finally, you can get this kind of sustain from a 16-kg stone guitar (this one homemade in Sweden I think):

[JonPorobil]

Wow. How much does it weigh?

[signboy]

Well, given the average weight per cubic centimetre of stone, the gravitational flux enhancement effect of Swedes, and accounting for the pickups and other such routing, I'd say it's roughly 16 kg.

[jb]

What does sustain have to do with the body of the guitar? Isn't sustain all about the nut, bridge, and string? I mean, I guess I can see an argument for the body dampening the part of the string that's after the bridge-- but really that's kind of minor. Tone on the other hand, I can see the body having something to do with that. Sort of.

[PlainSongs]

Good question, JB. I copied this "listen to that sustain!" from the Youtube blurb (it's without added sustain effect of course - or so it says), but then I wondered myself.

This page says:

"In almost all cases a solid body guitar has a much longer sustain than a semi-acoustic guitar. This is because the material of the body, i.e. the wood, helps the guitar sustain it's notes for longer. Therefore more wood there is, the longer the sustain."

So if air is less dense than wood and sustains less, it makes sense that stone (denser still than wood) sustains even more. What's the details of the physics though? Maybe it's just because the waves travel more slowly in denser material, and have a substrate for a longer time to keep on waving about in?
But on the other hand, too much material would inhibit the waves, you'd think. A foot-thick cymbal wouldn't work very well... or would it? Maybe it would be very faint but sustain a long time?

[Project-D]

A foot thick cymbal would work awesomely sustain-wise. The only problem is you'd have to hit it with a 20 pound hammer. In essence you'd have a church bell. They sustain forever but it takes a lot of energy to get them moving.

[jb]

But in this case, the virtue seems to be that the body *doesn't* vibrate. Thus allowing the string to vibrate longer because of less energy transfer from string to body?

I dunno man, not buying it. I suspect the diff between sustain on a semi-hollow and a solid-body lies more in the thickness of the strings and increased surface area contact with nut and bridge and tuners. I guess you could make a case for increased stiffness in the neck and such helping prolong sustain... and I *guess* you could chalk up some (miniscule) amount of sustain length to energy transfer from body through string... but still.

[adam b]

very dense materials conduct sound better, ie. less volume loss
string is attached to bridge which is attached to body, and the string vibrations move through all of these
hence, a body made from stone will dampen the sound less and thus sustain the note for longer in the string.

tone is dependent on the material structure and the guitar shape, as the movement and reflection of various frequencies will change with the material it's passing through.

[PlainSongs]

But in this case, the virtue seems to be that the body *doesn't* vibrate.

But it does, right?

I think of it this way now. You put energy into the object, which process turns mechanical energy into specific sound energy. If the object is dense it will trap the waves for a long time rather than transmit them quickly to the air for your ears to hear. So it will sustain well but it's quiet - unless, like Project-D said, you strike it very hard, or you amplify it. That's a downside of a stone guitar: needs more amplification.

Stuff must be ringing all around us but too quietly to hear...

With an acoustic it would be too quiet to use a big slab of dense material, so they are built for quick release of the vibrations to the air, which makes them loud but without much sustain.

Here's an appropriate tune on limestone:

[signboy]

I'm+pretty+sure+it's+a+simple+case+of+what+the+string+is+anchored+to.+
Eg%3A+have+you+ever+played+a+really+lightweight+bass%3F+They+sustain+like+an+upright.+
When+you+pluck+the+string,+it+actually+shakes+the+body,+transferring+most+of+the+energy+as+
the+body's+movement+acts+like+a+shock+absorber.+When+the+body+weighs+a+ton+(like+all+my+basses,+I+see+to+that),+the+string+doesn't+weigh+enough+to+shake+the+body+as+much,+
and+keeps+all+its+energy
.+There+are+plusses%2Fminuses+to+both+heavy+and+light+bodies,+but+the+weight+of+the+body+
DOES+directly+affect+the+guitar's+sustain.
[edit]
so, posting from a non-pda phone= no go.

clicks & whistles...

Okay, I have some signal again. What I meant was that... aw, never mind. Everybody gets it anyway. Tie one string to a
couch cushion, and tie another one to the coffee table. Then pull em tight and pluck em, see which one sustains longer.
Heavy body, neck-through design, and a solid bridge. Need that.

[Teplin]

The hell...?

[Henrietta]

I would think the ability for a solid body to sustain would be related to how much vibrational energy can travel though the body without attenuating. The string keeps vibrating, but over time the string vibration energy won't be as strong. A strong coupling and a dense body will transfer the energy a lot more efficiently than light materials or poor bridge coupling, and so is able to transfer perceptable amounts of energy from the same string for a longer period of time. If that makes sense.