Hi. I was wondering, does anyone know what makes 2 pickups wired together parallel quick and 2 pickups wired in series fat and smooth?

What is happening to make this difference and why?
Guitars:
Davison SG
Line 6 Variax 600
Line 6 JTV 69s
Squier Classic Bibe Telecaster Thinline
In a series circuit, the current through each of the components is the same, and the voltage across the circuit is the sum of the voltages across each component. In a parallel circuit, the voltage across each of the components is the same, and the total current is the sum of the currents through each component.

the difference is one sums the current, and the other sums the voltage.
I wondered why the frisbee was getting bigger, then it hit me.
Everything that Gregs said is 100% correct, but I was told that the quackiness of a strat comes from 2 single coil pickups, one of which is reverse-wound.

It's all basically motor theory. Electrical current, a magnetic field and relative motion. If you have any 2 of those, you can induce the third. That's how a pickup works. You create relative motion by plucking the strings and the magnets are in the pickup. The motion of the string through the magnetic field creates a small current. The direction of the current flow is dependent on the direction of the magnetic field (assuming that the string motion is the same in each case). So if you wind one pickup clockwise and the other pickup counter-clockwise, the RELATIVE direction of the magnetic field through each is reversed. When the string is plucked you get current flow in one direction from one pickup and current flow in the other direction from the other pickup.
If the pickups were both in the exact same spot (impossible) and constructed exactly the same (almost down to the atom - improbable) then they'd each generate an equal and opposite current flow that would cancel each other out.
But since they're not exactly the same and since they're separated by some distance they create alternating patterns of current that do not cancel. They're roughly the same shape but the waveforms peak at slightly different times. This is called "out of phase".

That's information that was borrowed from my electrical profession. It's good information but I'm not 100% certain that it's what's happening in the guitar. I may have connected some of the dots wrong, so I would love to hear confirmation from someone, or a correction if necessary.
^That's correct. It also explains why the 2 and 4 positions on a strat don't sound exactly like a humbucker - the phase cancellation is very different because the two halves are farther away, and sensing different portions of the string.

This is also why single coils have that distinct high-bandwidth chimey clean sound. Phase cancellation is, basically, distortion, in that it removes a part of the signal. A humbucker has some amount of phase cancellation inherent to its design, but a single coil does not. In a similar vein, this is why many humbuckers are purposely wound with one coil hotter than the other - manipulation of that phase cancellation gets you more of that single-coil type clarity, or the humbucker darkness and sustain, depending on how asymmetrical the coils are.
I think the quack is caused by the cancellation of some harmonics, but not because the middle pickup is out of phase, it's not, but because of the pattern of the string vibration...I don't think I can explain what I mean in English just look at the animated picture in this page http://en.wikipedia.org/wiki/Vibrating_string
Look for example at the first overtone, the first half of the string does vibrate with an inverse phase compared to the second half, if you place one pickup at 1/4 of the string length and another pickup at 3/4 the first overtone will be cancelled, even if the pickups are not out of phase.
Also as far as i know if you wire two pickup in parallel you'll cut in half the resistance and inductance of your circuit, and the resonant peak of the pickups will be at an higher frequency, this could help getting more quack.
On the other hand if you wire them in series you'll double the resistance and inductance, losing some highs (afaik the frequency response peak should be half the frequency peak of the same pickups wired in parallel) so you'll get a fatter sound

that guitar is like falling in love with a stripper
Silmeria
Valkyrie
modded Squier Strats
Quote by billyTheShears
I think the quack is caused by the cancellation of some harmonics, but not because the middle pickup is out of phase, it's not, but because of the pattern of the string vibration...I don't think I can explain what I mean in English just look at the animated picture in this page http://en.wikipedia.org/wiki/Vibrating_string
Look for example at the first overtone, the first half of the string does vibrate with an inverse phase compared to the second half, if you place one pickup at 1/4 of the string length and another pickup at 3/4 the first overtone will be cancelled, even if the pickups are not out of phase.
Also as far as i know if you wire two pickup in parallel you'll cut in half the resistance and inductance of your circuit, and the resonant peak of the pickups will be at an higher frequency, this could help getting more quack.
On the other hand if you wire them in series you'll double the resistance and inductance, losing some highs (afaik the frequency response peak should be half the frequency peak of the same pickups wired in parallel) so you'll get a fatter sound

@Roc - Thanks! Science!
@billy - What you're saying is related, and I've been thinking about the distance between pickups ever since I wrote my first reply, but I do know that strat middle pickups are conventionally reverse-wound. That's not an attempt to disagree with what you're saying except to point out that what Roc and I were saying is true and is definitely a factor. I would guess that the spacing of the pickups is also a factor.

I have also been wondering about scale lengths - and I wonder why the Strat and the Les Paul are the lengths that they are, and how the pickups were placed, or if they were even placed in their spot for any particular reason.

It makes me think that a different scale-length and some precisely located single-coil pickups could create cool sounds. Maybe there's a way to emphasize certain octaves over others?

Oh yeah and it makes me wonder if there was any particular reason for the PRS scale length. I think I'd be considerably less impressed with the thought process behind that if it's really just a compromise between Strat and LP. I'd be considerably more impressed if they were trying to be clever about the spacing as we've been discussing here.
Last edited by paul.housley.7 at Aug 28, 2014,
Yes, we agree that the quack is a matter of phase cancellation, however in my opinion is caused by the vibration pattern of the strings.
Middle strat pickups are usually reverse wound so the electromagnetic noise is cancelled when it's wired in parallel with another pickup, the trick is that it's also reverse polarity, so the vibration of the string does "distort" the magnetic field in the opposite way compared to a standard pickup, this way the phase of the signal is reversed twice, so it's back in phase (I'm no expert, just wikipedia wisdom )

I'm not sure about the scale length, probably they took in consideration playability and maybe string tension more than tone;
Also I think there's not a general rule about pickup placement, on strats the neck pickup is usually placed at 1/4 of the scale length (from the bridge), so it will pick as much of the first overtone as it can, but only when plucking an open string, the position of the overtones does change depending on where you are fretting the notes, for example at 12th fret the neck pickup does pick mostly the fundamental note, that's why it sounds duller.
Anyway on 24 frets super strats the 24th fret is placed where the neck pickup usually is, but it still sounds quite stratty even with the neck pickup in slightly wrong position

that guitar is like falling in love with a stripper
Silmeria
Valkyrie
modded Squier Strats
A lot is made of the placement of the neck pickup vs. where the harmonic nodes are, but I just don't think that's correct. As mentioned before, the minute you start fretting, the placement of those harmonics changes completely. I think the idea is similar, it still involves harmonics, but it's about amplitude, not nodes!

As you get towards the center of the vibration, you get a wider string amplitude. I'm sure you've noticed that the string vibrates more freely towards its center, simply because the closer you get towards the bridge or the nut, the more resistance there is from that force holding the string in place.
So let's talk about amplitude and vibrations. It you look at that excellent gif:

When you play an actual note, your string actually sums up all of those harmonics. They all happen at the same time, in the same vibration, because of course the string can only be in one place at one time. So you can think of your string vibration as all of those waves put together.
You'll notice that those high-order harmonics, by nature of being much smaller, have a great distribution across the string. That means you can pick them up anywhere. But now look at the fundamental and the first two harmonics. They're really wide, so at the very ends of the string, the amplitude is really low. That means that a pickup placed very close to the edge will not see that big amplitude. It will still pick up the fundamental, but as you get closer to the edges, the amplitude difference between the fundamental and the higher harmonics becomes very small. This is why your bridge pickup grabs harmonics so well - the difference in amplitude between the fundamental and the harmonic is reduced.
So, when you move a pickup towards the neck, it gets closer to the center of the vibration, and the fundamental amplitude is very high, and the harmonics' amplitudes become lesser in comparison. So you get a strong fundamental (bass) and a comparably weaker set of harmonics (treble). So this is why your neck pickup is usually bassier, and why neck pickups often are wound less than bridge ones, to make up for the inherent volume difference because the neck pickup sees a wider amplitude.
So you can see that the placement of the pickup is what determines what it "sees" harmonically, but it's not because of the harmonic nodes (because those are always changing, and actually you have the least motion of all at a node) but because of the harmonic amplitudes. When you move the neck pickup, then, like on a 24 fret, it's not the node placement that changes the sound, but the differences in amplitude that make it sound different as it moves closer to the bridge. This is also why, for example, if you pick very close to the bridge, you get a nasal, trebly sound: the amplitude of the string stays very narrow, so the fundamental is not as prominent as it is when you pick closer towards the middle of the string. In the same vein, this is why some people strum over the neck, especially on a strat, to get that warmer, more fundamentally dominant clean sound.

Short version: the bassier parts of the string's vibration live in the middle, the harmonics live everywhere but become more equal towards the ends of the string, so your bridge pickup is more trebly because it sees less of a difference between a higher harmonic and lower harmonics. This happens because the string vibrates more freely towards the middle so you get a higher amplitude, which is what the pickups are looking for in the first place.

Maybe I should draw a picture of this. I'm not sure that I'm explaining the idea very well.
Yes, with that example of the strat neck pickup I meant that there's not a strict rule, all the things you pointed out are correct.

that guitar is like falling in love with a stripper
Silmeria
Valkyrie
modded Squier Strats
After that explanation i need a cigarette.
Holy complicated.
Guitars:
Davison SG
Line 6 Variax 600
Line 6 JTV 69s
Squier Classic Bibe Telecaster Thinline
Quote by Roc8995

So, when you move a pickup towards the neck, it gets closer to the center of the vibration, and the fundamental amplitude is very high, and the harmonics' amplitudes become lesser in comparison. So you get a strong fundamental (bass) and a comparably weaker set of harmonics (treble).

That's why some people select the neck pickup when tuning (and some even turn the tone knob down), to get a stronger fundamental which (supposedly) aids with tuning (using an electronic tuner, I mean, the extra harmonics can confuse it if they're too prominent).

I understood what you meant just fine... but then I (sort of ) already understand what you're talking about
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I'll have to put the Classic T models on my to-try list. Shame the finish options there are Anachronism Gold, Nuclear Waste and Aged Clown, because in principle the plaintop is right up my alley.

Quote by K33nbl4d3
Presumably because the CCF (Combined Corksniffing Forces) of MLP and Gibson forums would rise up against them, plunging the land into war.

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Et tu, br00tz?
You can get some of that cluck in the middle position of a LP if the pups are of similar output. Not exactly the same, but enough to notice.
I wondered why the frisbee was getting bigger, then it hit me.
^ Yeah (or any dual humbucker guitar with a similarly-wired 3-way switch, really). You wouldn't confuse it for a strat, but it's a similar idea that's suitable for similar tones.
I'm an idiot and I accidentally clicked the "Remove all subscriptions" button. If it seems like I'm ignoring you, I'm not, I'm just no longer subscribed to the thread. If you quote me or do the @user thing at me, hopefully it'll notify me through my notifications and I'll get back to you.
Quote by K33nbl4d3
I'll have to put the Classic T models on my to-try list. Shame the finish options there are Anachronism Gold, Nuclear Waste and Aged Clown, because in principle the plaintop is right up my alley.

Quote by K33nbl4d3
Presumably because the CCF (Combined Corksniffing Forces) of MLP and Gibson forums would rise up against them, plunging the land into war.

Quote by T00DEEPBLUE
Et tu, br00tz?