Here are some excellent resources made available by
Ted Weber and Weber Speakers. These links open in new windows but you won't leave my site.
A lot of people ask me the difference between ceramic and alnico guitar speakers. I've posted Ted Weber's explanation below. Please scroll down below the wiring diagrams.
Ted Weber's direct technical support was invaluable to me and a lot of other musicians over the years. He will surely be missed.
General Speaker Q & A
Speaker Codes and Implementation
Here's some important information from Celestion about installing new speakers.
Ted Weber's explanation of alnico magnets vs ceramic magnets is from the Weber site and is used with permission. This and much more in depth tech info can be found by clicking on the "General Speaker Q & A" link above.
. The whole 'AlNiCo mojo' is about smooth compression at high average levels,
such as what you would have running the amp flat out. AlNiCo (Aluminum-Nickel-Cobalt) is an alloy magnet and all alloy
magnets are easier to demagnetize than comparable Ceramic (Strontium Ferrite) magnets. What this means
is that as the voice coil starts moving in response to the input signal, it generates a magnetic
field of its own that tries to demagnetize the magnet. As its effect lowers the available magnetic
field of the AlNiCo magnet, the speaker becomes less efficient, the voice coil moves less, etc.
The physics of it is that the small magnets near the surface of the magnet poles (called 'domains')
begin to change state, or flip directions. The result is smooth
compression, the same kind of operating curve compression that occurs in a tube amplifier.
The ceramic magnet, on the other hand, doesn't compress or demagnetize as easily, so the
voice coil moves to its mechanical limit and won't go any farther. This is why some players say ceramics
sound a little edgey at high average levels as opposed to AlNiCo. However, by properly designing
the entire magnetic circuit, Ceramics can be made to behave quite well for desirable guitar amp tone and dynamics.
You might compare the two magnetic circuits to solid state amps versus tube amps, where the
solid state amp gives it all its got then clips hard, while a tube amp compresses nice and
smooth. The extension of this idea, then, is that with the AlNiCo, like the tube amp, you can seem
to have a louder average volume since it gets compressed smoothly. By the
way, the compressing or demagnetization that occurs with the AlNiCo is not
permanent. It springs right back to its design operating point.
If you need more information, feel
free to contact me at firstname.lastname@example.org