Important to remember that Paul is in a privileged position.
He can spend all day tweaking one element of a guitar and listening to the effect.
He also plays and hears more guitars in a day than most of us do in a lifetime.
(of course as the guy who runs a fairly sizable company I'm sure he doesn't do this every day, although it appears he does more of it nowadays than he did for a while there)
Anyway, that volume of experience gives Paul a perspective that few of us civilians have. As civilians go, I've played a LOT of guitars. Moreover I've had some excellent mentors who have helped me develop my listening skills. (hearing details of guitar sounds is very much a learned skill, btw) Based on my experience, I agree in broad principle with Paul's premise that the elements that contribute to the sound of a guitar are essentially subtractive, although I'd characterize it more as a recipe with a lot of ingredients. The issue I have with the Principle of Subtraction is that the logical endpoint of it is some sort of objective "perfection," i.e., an instrument where nothing detracts from the optimum performance.
Unless you're talking about a particularly spectacular violin (and, even then...) I don't think objective perfection, or "the best" exists. There's only a relative "best" -- best of show, whatever. And even then that assumes a common set of criteria which I doubt is ever really the case when we're talking about guitar (or violin) players.
Anyway, I like that Paul continually strives to tweak each part of the recipe. AFAIC the guitars show it.
I'd also observe (again based on experience) that there are other guitar builders who gone even further back to the basics in terms of questioning accepted elements of guitar design and coming up with strategies to obliterate elements that have traditionally been an Achilles heel or a major subtractive element. Exhibit A: the bridge on Ken Parker's archtop guitar.
Well thought out and argued and I completely agree.
I am not 100% sure what Paul's theory of subtractive tone is; I haven't heard him talk about it.
On the other hand, I know very well what subtractive synthesis is, what the filters and envelopes do to the signal produced by an oscillator, and how to operate a subtractive synthesizer.
If you think of the pure note produced at the vibrating string, you have your oscillator. The parts of the guitar then act to subtract and shape, and even add resonance and harmonics, to that oscillating string. This is a thought I expressed a long time ago on another forum, or maybe here, and someone said, "That's what Paul Smith says, that a guitar is a subtractive device."
In synthesis, we talk about the effect of various tiny transistors on the sound of the synth much the way that guitar people talk about whether this pedal's germanium transistor sounds as good as that later copy of the germanium transistor - that measures the same, and should sound the same, but doesn't. No one can satisfactorily explain why. But most folks seem to accept this and move on without much argument.
In a similar way, people know that a Fender doesn't sound like a PRS doesn't sound like a Gibson doesn't sound like a this or that. All the brands of guitars, and all the different models, sound different. We have all experienced this. It's there because lots of small differences in construction add up.
The wood? Is it the neck tenon? Is it the scale length? The thickness of the headstock? Etc. On a macro level, two builders can make a solid body, mahogany and maple, set neck, stop tail, guitar and yet the guitars will sound different. Why?
Well, people like Paul Smith investigated the micro level. Maybe there are differences there, as with the transistor in my earlier example. Maybe the material used for the bridge mattered; maybe the paint mattered; maybe the type of wire used for the pickups mattered; maybe the metal for the fret wire mattered; maybe the type of plating on the bridge pins mattered...
I can say without qualification that the McCarty that arrived yesterday does not sound the same as the McCarty I bought in 2001. It sounds different. I personally think it sounds better, too, but that's beside the point. It sounds different. There are a lot of little reasons it sounds different, and the little reasons add up to something that to me, sounds better.
That's enough for me to say that Paul's ideas about tone, ideas that he's still developing, are good ideas. He's more likely than not, correct.
I can clearly hear the difference between my old McCartys and the new ones. I don't need to take the guitar apart to test the theory and substitute other parts. That's Paul's job, and he's done it well.
"Yeah, but it's mostly the pickups that are different."
Fine, I say (even though the headstock, tuning machines, bridge, plating, nut, paint and who knows what else are also different).
Why do the pickups sound different? The very thin wires used to wind them? The little magnets that are in them? The materials used in the bobbin? How the wire was wound? Et cetera. Et cetera. These are small things no one argues about any more, we can easily hear them because pickups are big, macro parts of guitar tone. However, they're also built on micro principles, just like guitars. They're made from lots of parts. And each part matters.
The tone of the guitars prove the point - because the point is the
sum of the parts.
If you hear the difference in the tone between a PRS and some other guitar, great. If you bought one, you've done so presumably because it sounds the way you want a guitar to sound. It comes closer to that tone in your head. In the Great Guitar Election, with hundreds of brands competing for your money, you voted with your wallet about the tone, and whether or not you like Paul's theory about these tiny little things, you still did what he wanted you to do, namely, play his guitar instead of someone else's guitar.
If you bought one for looks and not tone, you bought the guitar with your eyes, and you've proven another of Paul's theories - that most people buy with their eyes.
If you bought one because it feels right, you've done so because yet another of Paul's theories is that a guitar has to feel right, playable out of the box.
If you bought one because it smells good, you're pretty weird. I don't know if Paul has a theory on that.