Scatterwound Pickups

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Re: Scatterwound Pickups

I see some really good comments here. However no one has talked about the orientation of the magnetic field that surrounds a wire, its orientation to the rod type magnet as in a strat or a flat bar type magnet as in a humbucker or whatever the shape of the magnet. Take into account the fact that of these two magnetic fields one is constantly changing (the one flowing in the winding on the bobbin of course) in magnitude due to the vibration of the string/ mag-field-disruption or variation and the resultant ac signal due to amperes law of changing magnetic flux and conductors of various shapes (ours being a cylindrical long conductor = wire). This orientation I refer is directly related to the total magnetic field and the angles and shapes of the fields around the conductor and the perm/bar or rod type magnet.
That total magnetic field thus again by Ampere's Law and Faraday's law of emf (really Lentz's Law = Faraday's law in reverse direction or negative EMF), since an emf and thus a resultant current is induced back into the winding in the reverse direction for a brief period during which the ac signal is reversing direction as it cycles thru 2pi radians per cycle of per Hz. Thus this total package has an effect not only on the total magnitude of the ac signal = the music, but also the phase of the signal. Now I will admit that the human ear is mostly not sensitive to phase shift of an ac signal at standard audio frequencies, but that mostly part is the kicker. There are some parts of the constituent, spectrum of the signal that has phase content that is detectable to the human ear, thus color, maybe Oh so slightly the sound produced. Again, as many have stated, the difference is detectable but not to the extent that it would jump out at one, at all frequencies and magnitudes. Kind of like wolf tones in an improperly tap tuned acoustic guitar. As far as the microphonic differences, I am sure they also come into play but to what extent, I am sure varies with much more than just the way the pickup is wound, how it is mounted say for one thing and what it is mounted to and how much force or power the sound wave possesses to cause the microphonic to begin with. This is the science of, what is being discussed, here. I am not saying it is the end all reason, but definitely adds to the difference, where players, builders etc have detected a difference.
Here is a url to a pdf

http://www.phys.uri.edu/~gerhard/PHY204/tsl216.pdf

It will help one understand electro-magnetics, which is not electro-magnets, no insult, but you would be surprised how many people do not understand the difference between the two. All of this is classical freshman/softmore year study for electrical and computer engineers, any scientist or engineer for that matter and anyone attempting to seriously wind pups should at least educate themselves somewhat in this subject matter, pickup college text for physics used by engineers. A good on is called University Physics it is by Young and Freeman. A 12th edition copy can be had free off the internet in various places. Don't worry if you don't understand the math, if you only get the understanding of how the mechanism works and these orientations I talk about (using the right hand rule for instance) it will greatly enhance your understand of this subject. A good read on perm magnets would also be a really good idea and of course magnetic materials used and there difference both is basic metallurgy and the difference in the sound produced. I hope some of this helps someone. If anyone is interested in some of the math used I would be happy to help and step them through.

[looneytunesthemovie]

I am just beginning in pickup experiments, but something may have been missed so far here. Last week I read that neat and uniformly winding, so machine windings, create something called capacitance in between the wires, but scatter winding decreases this effect. In the space between the wires this capacitance is said to act as a sort of tone filter, reducing the top end. So the more windings you have, the more of the bass and middle get through to the amp. There are other complexities I am trying to understand such as using a nickle silver back plate on humbuckers, not a cheaper copper one, and the magnet strength. The stronger the magnet, the brighter (or perhaps the more ice picky?) the tone. Less windings, some scatter, and lower strength magnets, produce a bright but warmer tone? And not full potting, only half potted. Dunno. I am pulling cheap ones apart at moment to find out.

[Ewizard]

Scatterwinding does in fact reduce the amount of capacitance that can occur when the wire lays directly next to itself wind after wind. In a machine wound pickup that DOES NOT have a form of scatter winding programmed in, the wire will be neatly and uniformly laid next to itself. This increases the capacitance, thereby reducing high frequencies. Modern machines can have a scatter wind type of program loaded into them, but as you can imagine, it is not human by nature and will still be somewhat uniform. Hot pickups with a high DCR will be tougher to tell apart because the DCR and the number of winds are so high that you get high-frequency roll-off regardless.

I am not going to say that hand-wound pickups are better than machine wound, they are just different. machine wound can most certainly have more consistent results. I think hand-wound pickups just have more character to them. They are each a little bit different, but that human touch makes them a little more of something even if they are wound technically the same. Having wound several sets I can say that my winds are just as good as any commercially available pickups I have ever bought. I have even emulated one of my favorites close enough to say I have a copy.

Pickups are not magical devices, they are the sum of all parts. If the parts are all the same, they will sound the same, the human aspect is what makes them different. I think this is where custom pickups comes in hand. You can try a thousand machine wound pickups and never be totally happy, but you can have a custom winder dial in a set for you in probably 2 or three tries.