Ceramics vs Alnico

[Rog]

This from Bill Lawrence - pickup maker


When I read that ceramic magnets sound harsh and alnico magnets sound sweet, I ask myself, " Who the hell preaches such nonsense?" There are harsh-sounding pickups with alnico magnets and sweet-sounding pickups with ceramic magnets and vice-versa! A magnet by itself has no sound, and as a part of a pickup, the magnet is simply the source to provide the magnetic field for the strings. The important factor is the design of a magnetic circuit which establishes what magnet to use.

Though ceramic magnets cost less than alnico magnets of equal size, a well-designed magnetic circuit using ceramic magnets costs much more than the six Alnico 5 magnets of a traditional single coil pickup!

Aging

Before the introduction of alnico magnets in 1935, permanent magnets were not quite that permanent. During a certain time, they lost a good amount of magnetism till they finally reached a stable condition. The process to accelerate this decay was called in the industry, "magnetic aging." In modern science, it is called "stabilizing." Since the ‘50's, we use Alnico 5 magnets which lose, under normal conditions, less then half a percent per 100 years.

How do we achieve normal conditions?

Alnico magnets are shipped by the manufacturer in a non-magnetized condition and will not be magnetized until a pickup is completed.

How to maintain normal conditions?

After magnetization, avoid any close contact with other pickups or magnets facing either north to north or south to south with their magnetic poles. Don't ever throw pickups random in a drawer; you may either use a keeper on each side of the magnetic poles or carefully place them with the north facing the south pole of the other magnet. ( For tele players, remember that the iron backplate of a traditional tele pickup functions as a keeper which increases the stability of the magnets.)

Once pickups are in a guitar, there is very little to worry about. That your pickups lose some of their magnetism when you lean your guitar against an amp is nothing but a fairy tale. Or, that pickups lose some of their magnetism when you drop them on a concrete floor is just another fairy tale -- alnicos and ferrites will break before they have any measurable losses. Magnets are sensitive to heat, but so is your guitar. However, heat can be a severe problem when an Alnico 5 magnet is exposed to temperatures above 1000 F, approaching its Curie temperature of 1634 F. At these temperatures, Alnico 5 undergoes structural changes and cannot be re-magnetized. Why do I mention this? Because it happens quite often, when someone doesn't like the unbalance in output of a pickup with staggered magnets and goes to a bench grinder or a belt sander to grind a magnet down. You take a chance that a magnet gets too hot and becomes damaged.

[ash]

I'm going to play Devil's Advocate here. I'm sure he likes to think he's debunking myths, but really he's just stirring the marketing pot with spice of his own flavour...

When I read that ceramic magnets sound harsh and alnico magnets sound sweet, I ask myself, " Who the hell preaches such nonsense?" . ...

Though ceramic magnets cost less than alnico magnets of equal size, a well-designed magnetic circuit using ceramic magnets costs much more than the six Alnico 5 magnets of a traditional single coil pickup!

Which is why no-one makes properly designed ceramic pickups, because alnico works just as well for a fraction of the cost!! Leaving the cheaper ceramic equipped pickups in the 'poorly designed' category and often with the attendant deficiencies in their sound, in particular clean fullness and smoothness.

Since the ‘50's, we use Alnico 5 magnets which lose, under normal conditions, less then half a percent per 100 years.

And how many people do we know who use keepers on their pickups? Normal conditions rarely exist now in the vicinity of a player's axe, and they sure as hell haven't existed with those highly regarded pickups that are already 50 years old.
The difference between new strings and old strings is much less than half a percent too, but that doesn't mean we can't tell the difference

Everything old Bill says is true and fair enough, but not all of it is relevant to the real world, just HIS OWN marketing guff.

The difference between ceramic and alnico is so complex that I've never seen it explained to my satisfaction. I understand the fundamentals, but I can't explain it clearly myself either. Its just too hard to quantify without either going deep into dynamic magnetic theory or simplifying it to single statement, plain English sales pitch speak. Guess which one the pickup manufacturers will tend to use...

[Rog]

Whichever makes the most profit..

[artyone]

I've only wound one oickup in my life and I used neodenium magnets but I've got alnico magnets on most of my guitars that I like and have lots of old ceramic pickups lying around that have been stripped of the ceramic and are awaiting either neodenium or alnico.Ceramic to me seems gated whereby its unable to pickup,or should I say,its flux density is such that vibrations of the string above a certain frequency and below a certain strength are cut out and don't register.It may be that ceramic has a low bandwidth and its resonance is within that bandwidth.I'm sure the terms are wrong for the application but I think they serve the purpose.But alnico,not as strong a magnetic field,seems to have a wider bandwidth and even a resonce peak that suits being able to pickup audible harmonics.Neodenium seems to be a cross between the two where it has a narrow bandwidth and is more powerful than ceramics but it also has a unique flavour in being able to determine intricacies.I used neodenium on a bass pickup and it reacted well with the energy but was almost eerie in how it picked up things like attack and scratch...?It wasn't so good with upper harmonics but stronger in intricacy than alnico...so it was clearer!And speaker wise you just can't go past alnico for its ability to hear everything.

[goldtop0]

Crikey dick guys this is HEAVY stuff right here.........this could easily be, dare I say it, a hell thread from the USA

[ash]

Hehe... But unlike USA hell threads, us gentle kiwi folk can deal with alternative opinions and offer our own in good taste without causing a thermonuclear meltdown!

[TMG 03]

I like humbuckers, But I also like single coin. What difference does it make whats inside them ?

[ash]

The difference between Samick Poobuckers and Gibson Burstbuckers...

If you were to take a digital micrometer and measure every aspect of both kinds of pickup, they would measure out pretty much identically. Its the things below that tolerance the make the difference...

The magnetic material, those coil parameters mentioned in Rog's collection of Bill Lawrence pickup information and similar tiny little physical parameters.

They have the same size wire, same number of turns, same plastic bobbins etc, but I bet no-one would swap their Burstbuckers for some Poobuckers without a fight