Tannoy Stirlings on the way!

I'll be darned. You sent me back to look at the manual. Sure enough, it says the magnets are barium ferrite.  Dunno if that's the same thing you're calling "ceramic," but it certainly is not alnico.

Ceramic magnets are often used as a synonym for the kind of ferrite magnets ubiquitous to speakers. From online:

Ceramic (ferrite) magnets are composed of strontium carbonate and iron oxide. ... After the molding process, the magnetic material is then sintered at about 2,000°F. The sintering process is similar to that of kilning ceramic pottery, thus the popular name “ceramic” magnet.

I don’t know whether Tannoy’s barium ferrite magnets qualify as typical of "ceramic" magnets, but it looks like the nomenclature is based on a loose association (by processing) anyways! I assume the sintering process is extremely efficient at fashioning the kind of magnetic ring useful for speakers.

Interesting. Sintering came up in a different context, recently.  I'm thinking about getting a new cartridge.  One of the ones I'm looking at is the E.A.T. Jo No. 5.  The body of that cart is made by laser sintering some kind of powdered organic compound.

@mulveling thank you for the detailed information. I learned more about these speakers in your few concise paragraphs than all the videos and articles I’ve read.  Appreciate you taking the time. 

@mulveling Totally fascinating writeup thanks but I have a question, why couldn't they pair an Alnico magnet with the tulip waveguide? Or is it just tradition or users prefer the pepper pot sound?