Loudness & Projection...huh?

[Silly Moustache]

A little while ago, a fellow member asked me about different guitar model options - 000 standard scale and 00 short(er) scale 12 fretters (natcherly).
I know that Martin designed the original models, i.e. 2,1,0,00, and 000 to be suitable for various audience/venue sizes.

My friend was asking if the shorter scale 00 might sound muted compared to the 000 (I hope he doesn't mind my mentioning this).

Of course there are an infinite number of variables, that produce tone and such but I've always thought that there was a distinct difference between "loudness" and "projection", but I have trouble defining it.

This first occurred to me years ago when attending a Stefan Grossman concert in a Victorian theatre when (IIRC) Stefan was playing prewar 00 and a 000 martins. Due to some misunderstanding there wasn't a p.a. system, but with the audience's acceptance Stefan did the entire concert purely acoustically (to maybe 400 plus?) and we heard every note. So, whilst the 00 grand concert, and the 000 auditorium models seem small today - they certainly weren't short on whatever it is that makes a guitar "project" - even to us right up in the gods.

Anybody have any thoughts on the reason why volume and projection are net necessarily the same thing?

[stringjunky]

Originally Posted by Silly Moustache

A little while ago, a fellow member asked me about different guitar model options - 000 standard scale and 00 short(er) scale 12 fretters (natcherly).
I know that Martin designed the original models, i.e. 2,1,0,00, and 000 to be suitable for various audience/venue sizes.

My friend was asking if the shorter scale 00 might sound muted compared to the 000 (I hope he doesn't mind my mentioning this).

Of course there are an infinite number of variables, that produce tone and such but I've always thought that there was a distinct difference between "loudness" and "projection", but I have trouble defining it.

This first occurred to me years ago when attending a Stefan Grossman concert in a Victorian theatre when (IIRC) Stefan was playing prewar 00 and a 000 martins. Due to some misunderstanding there wasn't a p.a. system, but with the audience's acceptance Stefan did the entire concert purely acoustically (to maybe 400 plus?) and we heard every note. So, whilst the 00 grand concert, and the 000 auditorium models seem small today - they certainly weren't short on whatever it is that makes a guitar "project" - even to us right up in the gods.

Anybody have any thoughts on the reason why volume and projection are net necessarily the same thing?

Projection is how far the sound will travel but loudness is just the amplitude of the sound with no respect to distance. Projection implies that an instrument has a narrower, more focused sonic envelope; more beam-like. You could say a projecting guitar is loud at a distance but over a narrower area. i think stiff backs make for a more projecting guitar.

[Alan Carruth]

I'll modify stringjunky2's answer a little: IMO both 'loudness' and 'projection' are subjective; with the objective measure being 'power'.

So, 'power' is something you can measure. A dB meter gets you pretty close, but there are other ways if you need real accuracy. Power is a global measure; since the guitar puts out sound unequally in different directions, and at different frequencies, you need to make measurements all the way around and add them up to get the total power.

'Loudness', in my way of thinking, is your impression of the sound, usually from close in. It's related in part to the spectral balance of the output. Low frequency sounds tend to go out about equally in all directions, while higher frequencies are usually more or less directional, generally coming off the top and out of the hole, going toward the audience. Guitars that sound loud to the player and to folks standing nearby often put out a lot of their power in the low range, whereas ones that sound louder from in front than behind are more 'treble balanced'. There are a lot of subjective things in this, that I'm not sure we totally understand. People tend to think of large bass balanced guitars as having a loud sound, when in fact, smaller guitars that are more treble balanced are often putting out more power. I suspect that it's an association arising from the fact that big critters tend to have low voices. We're always a bit surprised when we see a small man with a deep voice.

'Projection' is related in part to how directional the sound output of the instrument is, and also the treble to bass balance. It's a measure of how far away you can be and still hear the thing. Again, it' more complicated that it might seem. 'Normal' hearing is most sensitive between 2000-4000 Hz, so an instrument that puts out a lot of power in that range tends to 'project' well. However, the 'peakiness' of the spectrum, particularly in that range, also seems to count. I have seen plywood topped guitars that had power in the high range but a 'flat' spectrum that simply didn't project very well. This probably has to do with giving the ear some variety to home in on: with lots of peaks and dips in the spectrum adjacent notes will have somewhat different spectra, which makes them more 'interesting'.

That's how I tend to think about this; there are probably lots of other justifiable ways to sort it out. The point is that while there may be some relationship between 'loudness' and 'projection', both of those are subjective measures: it's not hard to find instruments that put out the same amount of (objective) power but sort out differently in terms of 'loudness' and 'projection'.

[bufflehead]

An interesting question.

I had two concert ukuleles, both made by the same manufacturer of the same materials, but the travel version was thinner than the standard version. The deeper uke had more volume, but the thinner uke had greater projection. As part of this, the sound seemed to come out of the thinner instrument more quickly, as if it didn't have to rumble around inside before rushing toward its audience. It also seemed to have more "pop" than the standard-sized ukulele.

I actually preferred the travel model, and got rid of the original.

I think this is one of the reasons I enjoy my BBT so much. It's basically 15/16ths of standard dreadnaught size, but the body depth is only 4 inches. It doesn't have the volume of a dreadnaught, especially on the base end, but it has great projection. (And is significantly more comfortable to play.)