Amazing Alnico Speakers

First off, what are we even talking about?

Well, we mean the type of magnet used in a speaker drive unit. Any conventional driver will use a magnet. There are two types commonly used: AlNiCo and Ceramic.

There's quite a fan base for these vintage drive units and many claim they sound better than ceramic speakers. The question is do they actually sound better and if so why? This stir in the HiFi underworld appears to have been noticed by today's companies, who now offer their own AlNiCo units. So is there something in it?

What is Al-Ni-Co (Aluminum-Nickel-Cobalt)

Its an alloy magnet system and was very common in the 60s. Its more expensive than ceramic magnet material, so logic would dictate that it was used for a reason. Saba, Isophon, Goodmans, all top manufactures back in the day and all of them used AlNiCo magnets in many of their drive units.

"the AlNiCo sound"

This is all about compression and it only happens due to the nature of the AlNiCo magnet.


AlNiCo magnet has a delicate magnetic field, easilly drained by other forces. So when you send a signal to the voice coil in a speaker, you are generating an opposite magnetic field. The field generated in the coil pushes away from the AlNiCo field, causing the cone to push out. When you swap the polarity, the reversal happens.

The field in the coil is also interacting with the AlNiCo, it looses some of its power as the coils field is present.

When playing music, the louder the volume the greater the field in the coil. The AlNiCo magnet is constant but the coils field is jumping around and switching direction. The bigger the coils field, the more power sapped from the AlNiCo.








So to recap, when the fields are interfering, the voice coil field weakens the AlNiCo magnets field. As you increase the signal, the greater you weaken the AlNiCo.

If you weaken the magnet on a speaker, it becomes less efficient (you get less output volume). This is happening with every movement of the voice coil, tiny tiny amounts and at extremely high speeds.

So the AlNiCo magnet system is smoothing the sound, or, to be more accurate, compressing.

So there is a difference with AlNiCo speakers and to my ears they do sound "better" but of course there are many other elements to a speaker and a well designed ceramic speaker will sound better than a poorly designed AlNiCo.