Why Two Strats (Teles, Les Paul's) Sound So Different (It's NOT the Tonewood)

Why can two guitars from the same model range, allegedly with the same pickups, tuners and switches, sound just different enough so that you prefer one over the other? Shouldn't they be the same? Because modern manufacturing techniques? I watched a couple of videos on how guitar pots are constructed, and very enlightening it was.



There's a sweeper arm attached to the knob, which runs over a ring of resistive material. At both ends are bits of bare metal that the sweeper can reach. One of those ends is at 1 and the other is at 10. At those positions, there is no resistance. As soon as the sweeper gets wholly on to the resistive ring, there's resistance. (Half-on and half-off, the electricity sees the zero resistance half-off bit and goes down that path, so the sweeper is not on the ring until it's all on the ring.) This why there is the well-known leap in tone or volume change on reaching 0 or 10. Personally, I think that's bad design, but there it is masquerading as a feature.

It seems guitar manufacturers think that 10% variation on the resistance of the pots and the capacitance of the cap is acceptable. This means one guitar might have a 550k ohm pot and another a 450k ohm pot, which is more than 20% different, which you will be able to hear. A 0.022 microfarad capacitor (a popular choice for tone controls) would vary from 0.0198 to 0.0242 microfarads, and that makes a difference of e.g. 3,000 ohms (!) in the reactance to A440, which is 16%, and that will also be noticeable.

That's why one Fender or Gibson sounds better than another, because the components vary so widely. (Paul Reed Smith says we can go into any guitar store anywhere in the world, pick out the same make and model of his guitars, and it will sound the same. Which if it is true means his manufacturers are doing some wicked quality control. If so, how did they miss the dry solder joint in my 594?)

But here's the thing.

The difference between any two guitars played through the same amp with the same settings is most noticeable when playing clean, and with either wide-open or mid-point dial settings. Reverb and delay blur the details, as does modulation (chorus, flanger, tremolo, phaser, univibe), and once the distortion goes beyond edge-of-breakup, no-one can tell the difference between a £100 Harley Benton S-style and a £6,000 Les Paul. Add enough effects and no-one can tell if you are playing a Custom Shop Jazzmaster or a Squire 335. A few dozen kilo-ohms difference between the pot values will vanish in the noise.

So that, I think, is why guitar-makers feel they can get away with what hi-fi manufacturers would blanche at. Anyway, this is about tradition, and traditional construction was even more erratic. Manufacturing has come a very long way since 1980 and even 1990, but guitar electrics did not seem to join the ride.

If Fender is prepared to use skanky (because that's what taking kit from the 10% bin is) guitar pots, why wouldn't they do the same for their amp pots? Makes a mockery of all those settings for this and that tone (you know, "to get that so-and-so sound, use 5 on the treble, 6 on the mid-range and 3 on the bass") because the writer's 5 may well be my 6 or 4. It really amounts to no more than "keep twiddling, it's around there somewhere".