alnico 3 the bi-polar magnet.

Ok, all magnets are bi-polar I know, but when looking at how winders describe Alnico 3 there must be many different variations. Some say it is clean and bright, others say warm and jazzy whilst still others warm and bright.

I also know that if you get technical magnets in and of themselves do not have a "sound", but you do have a good idea of what an Alnico 5 sounds like verses Alnico 2.

So, what is Alnico 3?

I think the variations in tone would be how the pickup is wound, and that would hold true no matter what type of magnet alnico or ceramic or other is used.
Like you said, magnets do not have a sound, they are just part of the formula.

A lot of people don't like the alnico 3 pickups that came in the Highway One Teles, but I tried one of the Hwy 1 neck pickups in a Tele a while back and it sounded great, not muddy at all , to my ears, just a full range of good tones.

I ask because it seems until recently everything was Alnico 5 or 2, but now people have realized that the pre-Telecaster Fenders used Alnico 3 at least some of the time and it seems to be a love it or hate it magnet type. (for what ever reason) And, I am looking at pickups for my first build, a Jazzcaster, and the Broadcaster pickups often come with Alnico 3 and a hefty wind!

I am not a big fan of overwound pickups due to the increased compression and often the loss of upper harmonics. I do not know what is in my wonderful sounding LsL T-Bone as far as magnets or wire, but I would like to get something similar though just a tiny bit hotter. I just wish Lance would sell me a set of T-Bone pickups!

Do I understand correctly that you'll be putting single coils in the Jazzcaster? If so.

If you want the clarity of the vintage pickups the CS Nocasters are Alnico III's but not overwound like the ones in the Squier CV VB. The readings on mine are Neck 7.1k and the bridge is 7.3k. To me they're full, bright and punchy, not at all harsh.

I have Alnico V's in my MIM. The output is lower and they're a mellower sounding pickup than the A III Nocasters. I'd describe them as "sweeter" sounding and less punchy. I like the sound of those as well.

In between those two are my Keystones which are a very transparent sounding pickup and again a little more laid back and "sweeter" than the CS Nocasters. They have a bit higher measured output; Neck 7.98k, Bridge 7.63 but because of that transparency the perceived volume seems less than the Nocasters. Still a lot of twang and punch but not as full sounding as the Nocasters and I don't mean that in a negative way. I think that's what makes these so unique. That transparency.

I don't know exactly what you're looking for and maybe you've had some experience with these pickups before but if not I hope this helps a bit. These are just my perceptions of them in comparison to one another.

'Bi-polar'?

Good blues pickups then...

Of course, there are several factors differentiating magnet types, but a few we know of that can indirectly affect tone are gauss level and isotropy. AliNiCo V is anisotropic. Isotropic magnets are less directional. They should have a slightly more spread out aperture. The resultant field can also cause phase cancellations within the coil, depending on the size and orientation of the coil. However, more pronounced frequency anomalies occur in larger coils, anyway.

Gauss levels can change dramatically depending on magnet lengths -- not sure of the details on that. AlNiCo V is generally higher power. Among other factors, the transfer characteristics of a pickup depends on the total design and materials. In general, AliNiCo V produces more bass, because bass is the first thing to go as the field strength decreases.

Perhaps, the sweetness factor we associate with the lower power AlNiCo's is merely a result of the the preamp input stage not being driven as hard? Perhaps, the broader aperture affects the attack? Maybe there are signature mid-range effects due to isotropy? Even so, these effects and maybe some others will vary depending on overall design, and production consistency. Therefore, how can anyone say what kind of sound a magnet type will produce?

I'll be the first to admit my technical knowledge of pickups is sparse at best. I've learned a few things from the guys around here but every time I read more I realize just how little I still know.

Therefore, any info I can provide comes from what my brain tells me my two ears are hearing and I can only describe it in non-technical terms. FWIW it's worth, as musician, I've always been told I have a good pair of them.

Hopefully my descriptions will make some sense. I realize we all hear differently and that the only true way to discern the difference between two pickup can only come from listening to them and making ones own judgement.

So what I offer is just an opinion in the broadest sense of the word and simply based on my impression and not founded in any deep technical knowledge of the why's and wherefore's.

Of course, there are several factors differentiating magnet types, but a few we know of that can indirectly affect tone are gauss level and isotropy. AliNiCo V is anisotropic. Isotropic magnets are less directional. They should have a slightly more spread out aperture. The resultant field can also cause phase cancellations within the coil, depending on the size and orientation of the coil. However, more pronounced frequency anomalies occur in larger coils, anyway.

Gauss levels can change dramatically depending on magnet lengths -- not sure of the details on that. AlNiCo V is generally higher power. Among other factors, the transfer characteristics of a pickup depends on the total design and materials. In general, AliNiCo V produces more bass, because bass is the first thing to go as the field strength decreases.

Perhaps, the sweetness factor we associate with the lower power AlNiCo's is merely a result of the the preamp input stage not being driven as hard? Perhaps, the broader aperture affects the attack? Maybe there are signature mid-range effects due to isotropy? Even so, these effects and maybe some others will vary depending on overall design, and production consistency. Therefore, how can anyone say what kind of sound a magnet type will produce?I think the sweetness is the magnet. I've got some great sounding full spectrum, even flat,(no peak) ceramic p/ups and none are sweet. I disagree w the "magnets don't have a sound" outlook. I have some 4.7K Velvet Hammer Strats, a 7K Pearly Gates HB, and a Fender Atomic 2 15K HB and they all share a sound quality that comes from the magnet despite being completely different in resonance, voicing and topology in the case of the hammers.

Oooops forgot, I saw an article that mentioned that as a p/ups magnetic field moves along the string its phase starts changing after a certain distance.

I think we can agree that using terms like "sweet", and "warm" to describe sound is somewhat nebulous. Even if there is some consensus, there's an awful lot of leeway regarding specifics. How does a term denoting a sensation of taste translate into sound? Most people probably associate a gentle high-end roll off, and big round bass with warmth. So, why do people equate even harmonics to warmth, when odd harmonics denote "heat". Shouldn't even harmonics sound "cool"?

It's true, magnets don't have a sound. Materials in, or around the core (inside the coil) have certain affects on the signal in the coil. Ceramic actually has the least affect of all. Isotropic AlNiCo III has nearly identical affects on inductance, Q factor, and AC resistance as the other AlNiCo's: not very much compared to some steels and high iron content materials. AFAIK, the main difference is it has the lowest energy product of the AlNiCo's. I think, since it has no Colbalt, it's also the least stable.

Still, whatever the affects a magnet/material imparts on the signal, there's really no way to deduce from magnet type how a pickup will register string vibration. Several other factors will affect the signal at the preamp input. Things like picks, strings, bridge/saddle material/design/mass, pot values and cable capacitance should also be considered in achieving a tone with a given guitar.

it's the whole enchilada that matters, not just the magnets - bobbin foot print, magnet type and dimensions, magnet charge, coil wire, wind tension and tpl, turn count, bobbin base.

I find my alnico 3 pickups to be a hair brighter and the attack a little softer than 5's. Lollar says his alnico 3 pickups are his brightest. Mine are Klein 52's.....still not night and day difference between 3's and 5's. A lot of it has to do with the strenth/gauss of the magnet too....more variables. At least this is what I see from my experience, ymmv.

Magnet strength vs coil winding is a big factor.

You can use very strong magnets that are very small and get a particular field shape around the coil, or you can use weaker magnets in a larger size to create a whole different field shape. They will sound different.

Just look at a WRHB with 5/8" long CuNiFe magnets and then a repro using other types of magnets. The other magnets are considerably smaller and therefore create a different field.

We use one length of alnico v magnets in our 10.5K MOD2 WRHB, and a smaller length of alnico II in our 8K MOD1 WRHB.

The magnet type is determined by the strength and size required to get the desired sound.

So you can't really say one magnet sounds this way, while another sounds that way. It becomes a matter of finding the right magnet/magnet size/coil wind, to achieve the desired result, and while this might work one way with rod magnets inside the coils like Strat and tele pickups, a completely different set of specs applies to bar magnet humbuckers.

It's really cool, fun stuff to work with.

I guess to me the best thing going is that there are guys out there like some of you who can make a really great pickup and all I need to do is listen to them and decide which one I like the best for the tone I'm after. Then pay you for them of course.

The science involved with playing them and getting what I want out of them is enough to keep my interest up without needing to know just what kind of materials are involved and the process of manufacture. That I'll leave to the pros.

But I do appreciate the fact that you guys are willing to share that knowledge even if it does sink in very slowly with me.

What has been said above is valuable.

There are two factors of interest with any magnet - the field strength and the flux density.

Alnico magnets exhibit a high flux density, that is the lines of force are close together. This is valuable in a pickup because it allows a good dynamic range.

Alnico are also powerful magnets, they can have a high field strength. In practice a pickup does not need a high field strength, this can pull the strings down. So an Alnico can be gaussed up to maximum and then de-gaussed down to the desired field strength. The Alnico magnet used in pickups are also relatively small.

It is the ratio of flux density to field strength that is important in an alnico pickup.
The various Alnico 'number' magnets exhibit different flux density to field strength ratios.

The pickup works by the string interrupting the magnetic field around the coil and so inducing a current to flow in the coil.

After that is is the design of the pickup, and this is where the witchcraft begins

A lot of people don't like the alnico 3 pickups that came in the Highway One Teles, but I tried one of the Hwy 1 neck pickups in a Tele a while back and it sounded great, not muddy at all , to my ears, just a full range of good tones.

When it comes to single coils, I have heard more complaints about a3 magnets than a2 or a5. I've heard complaints about the Hwy 1 pickups too, and also the Fralin Real 54s. That makes me wonder also if it isn't particular pickups that people don't like. OTOH, a3 is the weakest of all of the Alnicos, so maybe that is part of the problem for some.