How do Alnico ratios equate to tonal differences between magnets?

[yagguh]

Something I've never been able to wrap my head around when I began winding pickups was how different values of Alnicos affected the voice of a pickup. At face value, the lower the general output of a magnet the quieter the pickup becomes; how does the different blends of Aluminum, Nickel, and Cobalt contribute to a magnet sounding more scooped with accentuated highs and lows, or a magnet that has softer highs and lows with more focused mids? Of course, these descriptions are subjective but from what I've picked up online they're sort of the general consensus for how each magnet sounds.

So back to the main question, how does this blend of materials and how is the way theyre blended relative to one another change the tone of a pickup?

Something that also made me think about this was Bill Lawrence saying something about how a magnet is just a magnet and its only job is to create a field after responding to statements of ceramics sounding sterile and cheap.

[Mike Sulzer]

Something I've never been able to wrap my head around when I began winding pickups was how different values of Alnicos affected the voice of a pickup. At face value, the lower the general output of a magnet the quieter the pickup becomes; how does the different blends of Aluminum, Nickel, and Cobalt contribute to a magnet sounding more scooped with accentuated highs and lows, or a magnet that has softer highs and lows with more focused mids? Of course, these descriptions are subjective but from what I've picked up online they're sort of the general consensus for how each magnet sounds.

So back to the main question, how does this blend of materials and how is the way theyre blended relative to one another change the tone of a pickup?

Something that also made me think about this was Bill Lawrence saying something about how a magnet is just a magnet and its only job is to create a field after responding to statements of ceramics sounding sterile and cheap.

Magnets can affect the electrical properties of the circuit as well as doing their main job, that is, magnetizing the string. So BL's statement is not complete, although I think it is correct in context. There certainly is not such thing as a sweet sounding magnetic field! However, magnets can have low but significant permeability, which affects the inductance. They also can have signifiant conductivity, meaning that eddy currents flow, damping the resonance from the pickup inductance and the total of the capacitance (cable and pickup).

[zparts]

For pickups where we are mostly concerned with the tonal characteristics of a magnet, things like the amount of cobalt used, unoriented vs oriented, strength, and inductance are the differences mostly noticed if comparing the "sound". Even though technically it's incorrect to describe that way, pickups are perceived to produce sound for musicians so that's how we relate the magnets by default.

[Antigua]

Something I've never been able to wrap my head around when I began winding pickups was how different values of Alnicos affected the voice of a pickup. At face value, the lower the general output of a magnet the quieter the pickup becomes; how does the different blends of Aluminum, Nickel, and Cobalt contribute to a magnet sounding more scooped with accentuated highs and lows, or a magnet that has softer highs and lows with more focused mids? Of course, these descriptions are subjective but from what I've picked up online they're sort of the general consensus for how each magnet sounds.

So back to the main question, how does this blend of materials and how is the way theyre blended relative to one another change the tone of a pickup?

Something that also made me think about this was Bill Lawrence saying something about how a magnet is just a magnet and its only job is to create a field after responding to statements of ceramics sounding sterile and cheap.

I think the first thing to know is that there is a lot of misinformation about how magnets affect sound from guitar manufacturers, for example one major manufacturer says on their website "Alnico 5 magnets for more focus and enhanced dynamics" and that creates an expectation of complexity that doesn't really exist.

There are two main effects, 1) if the magnet is stronger, it will pull on the strings more, and that will cause the string to vibrate increasingly asymmetrically, and will move more of the kinetic energy to the harmonics, in the same way as "pinch harmonics", but to a much more subtle degree. In general, the stronger magnetic pull results in more treble content. Note that this is no different from the effect of raising or lowering a pickup, again to the effect of increasing or decreasing magnetic pull. A lot of the difference people say they hear with different magnets is likely to be identical to the difference they will hear as a result of raising or lowering a pickup.

2) If the magnets are in the form of pole pieces, like a Fender pickup, then the permeability of the magnetic allow will have a significant roll in determining the inductance of the pickup. AlNiCo 2, 3 and 4 will cause a higher inductance than AlNiCo 5, because they have more iron in them, with a difference of around 300mH. So for example, a Strat pickup with AlNiCo 5 might have an inductance of 2.2 henries, if you removed the A5 and pushed in A3 magnets, the inductance would increase to about 2.5 henries. That change in sound might lead some to believe the difference was inherent to the magnet, but it would be inherent to the inductance, and therefore the resonant peak of the pickup. With a PAF style humbucker, the magnet is outside of the coil, and only alters the inductance by about 20mH, give or take, and so nearly all of that difference is strictly due to the difference in magnetic pull upon the strings.

So there are real reasons for their to be a difference in tone, but they are not differences which are unique to the magnet itself, and the perception of that difference gets infused with a lot of imagination and marketing magic, like that quoted above.

[Helmholtz]

AlNiCo 2, 3 and 4 will cause a higher inductance than AlNiCo 5, .

The recoil permeability is about the same with A4 and A5. Arnold specifies µ = 4.6 for A5 (other sources range from 4.6 to 5.4) and µ = 5.2 for their A4.
My own inductance measurements confirm this.

So if a different magnet type noticeably increases inductance compared with A5, it's not A4.

Lots of fake A4 around.