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Is weight of a finished acoustic really that critical? I know that some people have preferences and limitations, but...
Having done some restoration on old pianos, I`ve come to realize the stability and strength of hard maple that is used in the pinblocks and the action parts. I own one that turned 100 years old last year, and aside from dust and battle scars, things have aged well (which I can`t say for myself).
Granted, we don`t want an upright piano sitting on our knees!

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Give me 50 cents worth of regular.
Check my oil too, if you don`t mind,,,

Thats a hard question to answer, everything plays a roll in the final out come or sound of an acoustic guitar. If you PILE on the finish, you'll likely kill the tone, if you use a 10 lb neck, the guitar will fall off your lap, if your guitar is heavy for reasons of an overly thick top and or back and sides, again, your probably gonna kill the tone. So yes the weight is important, just how much weight are you talking about

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Lance@LuthiersForum.com

Actually, I am referring to the overall weight of the finished guitar, but mainly the weight of the basic materials of the body and neck. Recently mentioned using maple as my primary wood of choice due to the abundance in my occupation with a co-worker who plays electric. The response was a roll of the eyes and with a heavy sigh, he replied, "I don`t want a ton hanging around my neck and shoulders for two hours at a time"
I realize the difference without actually having to compare apples and oranges, but any input is appreciated.

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Give me 50 cents worth of regular.
Check my oil too, if you don`t mind,,,

Well, it's very important to realize that some of the very best guitars in the world are feather weight - you almost don't realize you are holding them.

It's equally important to realize that some of the very best guitars in the world are very heavy - laminated sides, double backs, etc.

Different designs call for different weights. There's no way to say a lighter guitar is 'better'.

whilst it is true that with an electric the overall weight can get to be quite considerable if solid bodies are built from dense woods, this is not a consideration of such importance with acoustics due to the thinness of the parts involved. and many great acoustic guitars are built with maple.

perhaps of more importance weight wise is balance, for an inordinately heavy neck attached to a light weight body will require the player to support it instead of hanging in balance which can be quite tiring and inhibit playability .

that being said, some great acoustics are being built using an incredible variety of woods, some lighter, some heavier, and some quite heavy, but the overall weight of the instrument has not been much of an issue to my knowledge.

Thanks for the input. Now the hard decision...Horseshoes or tire wieghts on the tail block?

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Give me 50 cents worth of regular.
Check my oil too, if you don`t mind,,,

[QUOTE=Cocephus] Thanks for the input. Now the hard decision...Horseshoes or tire wieghts on the tail block? [/QUOTE]

Niether...just a bag o' lead shot through the soundhole. Then you can adjust the weight distribution!

On acoustics it seems that a light _top_, particularly in the lower bout, is a good idea. There's only a limited amount of horsepower in the strings, and that's the part that makes most of the sound. If it's too heavy the strings won't be able to move it much.

From what I can tell now it might be a good idea to have a fairly heavy back. The back tends to 'steal' energy from the more effective radiator of the top, so making it hard for the back to move (for the most part) seems like a good idea.

Some poeple swear by heavy liners. I dunno.

There is a resonance of the whole body moving like a xylophone bar at low frequencies that can work with the air moving in and out of the soundhole to produce sound in the bass range: arounf low G or so. Normally this 'neck mode' is too low in pitch to help out, but sometimes you can get it. Since the headstock and neck are moving a lot it helps to make them as light and stiff as you can.

You can hear this 'neck mode' if you hold the guitar up so that it hangs freely by pinching the neck right up around the nut between your thumb and finger. Tap on the back of the headstock up near it's top end, and listen for the low pitched sound as the headstock moves. The air resonance can be found by singing into the soundhole if you're a bass or baritone. You can also pinch the low E string as tightly as possible between your thumb and finger up near the nut, and pluck it while sliding your hand up and down to change the pinch point. The string will not ring out clearly, but will be noticably louder at the pitch of the 'main air' resonance that you are looking for.   

I tend to keep the neck light if I can, but I have found that ample can be stiff enough to work ut well, particularly if you make a deep V-shaped profile.

[QUOTE=Alan Carruth] ...From what I can tell now it might be a good idea to have a fairly heavy back. The back tends to 'steal' energy from the more effective radiator of the top, so making it hard for the back to move (for the most part) seems like a good idea. [/QUOTE]
This concept intrigues me. From what I have read of Kasha/Schneider theory, the neck should be as stiff as possible. From a number of top-notch classical builders, the sides should be as stiff as possible (thus the 2-ply rims, as well as solid linings on the rims.) Now, you're saying the back should be as stiff as possible.

I guess that leaves the soundboard, top bracing and the bridge as the only components that should be engineered to move.

Do your findings conflict with the builders that are using softwood for backs (and engineering the backs more like tops), or is that a whole different animal? Is the problem (of robbing energy from the top) with typical backs because the back's bracing, density, and MOE make it impossible for most back to resonate at the same frequency as the top?

Dennis

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Dennis Leahy
Duluth, MN, USA
7th Sense Multimedia

Dennis brings up a good point.

Backs are far more variable than tops, and this is not surprising. The top accounts for most of the sound, and poeple have pretty well homed in on the 'best' ways to make them. The back presents you with the opportunity to employ different strategies, depending on the wood and tone you want to get from it. Most makers go with the 'heavy and stiff' strategy, for the reasons I posted.

Another workable stategy is to use a light back that can move a fair amount of air itself. Mahogany and Spanish Cypress backs don't weigh much, if any, more than the tops do, and can move comperable amounts of air. Most of this, of course, is pumped through the soundhole, so the main beneficiaries of it are the lower note around the 'main air' resonance. It also adds a lot to the 'attack' part of the sound, and (usually) cuts down on sustain, and this seems to translate into a 'bright' tone even if there is not a lot of energy in the high frequencies.

As far as making the soundboard and bridge as the only 'moving' parts, that's the Smallman strategy in a nutshell. It's also the way resophonics work, and I'll nte that the one Smallman I got to spend any time with sounded to me like a wooden Dobro. I gues I'm just not the player that Williams is....

Alan, Thanks for the clarification, and the info.

I have a hunch that the lightweight backs that are engineered to move like tops would work best if they are engineered to flex in tandem (or more precisely, in sync) with the top. Otherwise, I envision something akin to "noise cancellation" (except, this is hopefully not noise!)

This also makes me think that a stiff back would not be advantageous on a guitar without a soundhole.

Question: Can the sonic advantage of a stiff back be demonstrated by simply holding or removing a hand on the back of the instrument when strumming, or does too much dampening come into play to hear the advantage?

Dennis

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Dennis Leahy
Duluth, MN, USA
7th Sense Multimedia

I 'tune' my backs to work with the top as much as possible, and they're a liitle 'looser' than some. Other people like the tone with a really stiff back. Whatever: there's no 'right' answer; just what you like.

Touching a light, flexible back certainly makes more of a difference in the tone than touching a heavy, stiff one, and touching the back of an Ovation doesn't do much at all.

alan, i must disagree with you most vehemently!

touching the backs, and the tops, of ovations with, say, a nine pound sledge, or an oxy acetylene torch, can have great cathartic benefit.

Very good Michael

Incidentially I keep fish in Mine, which you have to say is a definate advantage over a conventional acousticRussellR38561.7597453704

take the neck off and you have a coracle for the litte folk! or i suppose you could affix a mast and use the neck for a bowsprit, hoist a mainsail and spinnaker and enter the little folk in the sydney to hobart or similar.

I think we just got ourselves jobs in the marketing department of ovation

and your poor little piscan friends, being forced to live in such substandard digs; the rspca may get on to you for cruelty!

Well it said it had a bowl back so I thought it would be fine. Ihave noticed they become agitated when you plug the pickup in.

I've been wanting to get one for years to make into a planter: hang it on the wall with Swedish ivy coming out of the hole.

Ther is no end to thier usefulness Alan

One word..."litterbox"

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Don Atwood
Arlington, VA

can you pass on the secret to getting your cat to recognize and use the hole?