Ceramic weaks AlNiCo?!

[Artur pickupmaker]

A pickup maker said he doesn't install ceramic and alnico pickups in the same guitar because ceramic weaks alnico. Many people like me didn't believe it.
Today I saw this video he made:
YouTube - Alnico x Cerâmico

He touches alnico and ceramic magnets (observe he touched the opposite polarities, so it's strange a magnet loose strength, even if it were a neodimium the AlNiCo should gain strength) and mesured a loose of strength in AlNiCo.

What do you think about this video?

[David Schwab]

Yes, if you touch a ceramic onto an alnico you might make the alnico a little weaker.

But you can install them on the same guitar with no problem. The magnets will never touch each other, and also they are installed inside the pickups.

There are pickups that use ceramics and alnico in the same pickup, such as the DiMarzio Area J. I've seen people do it with P-90s also.

[Artur pickupmaker]

1-In a P-90 the two bar magnets touches the polepieces or shim. In this case AlNiCo doesn't loose strength?

2-If this magnets were close to each other, will AlNiCo loose strength?

This pickup maker says that if two pickups with this two kinds of magnets were installed in a guitar, the AlNiCo one will loose strangth after many years.

[FunkyKikuchiyo]

In terms of the flux lines of magnets of this size, the couple inches separating two pickups in a guitar may as well be miles. Touching them will affect it, but that proximity won't do much if anything. I think you'd have to put two strat pickups side by side to look like a humbucker each with magnets mounted on the bottom, one ceramic and one alnico in order to recreate this theory.

I had tried some experiments of charging the string with a magnet opposite of a pickup, changing polarity of a pickup on the fly (quick and dirty with a big neo-d) and a few other things, and you have to be really close to the pickup to do anything. It was an attempt to see if the string has any slight magnetic charge of its own that interacts with the function of a pickup, I had no idea so I figured it was worth a shot. The "string charging" thing made absolutely no difference in sound, so the string isn't making a bridge across the pickups to affect their strength.

I think it is a great lesson for storing pickups, though. We've all just thrown them into ziplocs and then into a box where they inevitably just stick together. Of course, sticking together with opposite polls would strengthen the pickups rather than weaken them, it still isn't good especially on bar magnets.

That's an interesting point on the p-90s, but I'd have to say that whatever happens to them is part of the desired effect of said pickup design, right?

[David Schwab]

This pickup maker says that if two pickups with this two kinds of magnets were installed in a guitar, the AlNiCo one will loose strangth after many years.

That's simply not true.

[Artur pickupmaker]

That's an interesting point on the p-90s, but I'd have to say that whatever happens to them is part of the desired effect of said pickup design, right?

Thats what I want to know, if I would like to make a P-90 with a AlNiCo and a ceramic bar magnet, if the AlNiCo will loose magnetic strength after some years.

In the video the AlNiCo bar looses a lot of strength, from 2,65 to 1,85 (don't know what mesurament unit is).
Who recorded this video says that a AlNiCo middle single coil of a Strat looses considerable magnetic strangth after many years if there is a ceramic pickup in the bridge or neck positions. I want to know if it is truth.

[David Schwab]

Thats what I want to know, if I would like to make a P-90 with a AlNiCo and a ceramic bar magnet, if the AlNiCo will loose magnetic strength after some years.

In the video the AlNiCo bar looses a lot of strength, from 2,65 to 1,85 (don't know what mesurament unit is).
Who recorded this video says that a AlNiCo middle single coil of a Strat looses considerable magnetic strangth after many years if there is a ceramic pickup in the bridge or neck positions. I want to know if it is truth.

The difference is that in a P-90 the two magnets are very close together with the opposing poles touching the keeper or poles.

On a Strat there is quite a distance between the bridge and middle pickups.

Pushing two magnets together to demonstrate that the ceramic will degauss the alnico is not a good test to show if two pickups in the same guitar will have the same effect. And they wont.

Also sticking an alnico on a ceramic with attracting poles together probably wont degauss it. But that depends on how you pull them apart. After all, you can use strong magnets to charge alnico, right?