Notable very small loudspeaker companies (other than Tekton!)

Tyler Acoustics, for sure. I've had Linbrooks for ten years. They are very precise, good soundstage, slightly warm (but I like it), they fill a room, and they're not highly directional. Bass below 30Hz, Highs beyond audible (for me). Excellent prices--the drivers are all Seas, believe it or not.  If you like Joseph Audio speakers (which at $7,000+ I consider more than they're worth), you need to listen to Tyler's.
I also admire Volti Audio products very much, although that's a very different kind of speakers. But they have gotten expensive, and Greg won't sell his multiple product items separately, only by a full set.
Both of these are built by hand by the proprietor.

Here’s a few more: Vapor, Ascend Acoustics, Evolution Acoustics and Klinger Favre.

Hi highly recommend Silverline speakers. I have owned three of their speakers with the Bolero being my favorite. So musical. They just sound so right. 

Source Loudspeaker Technologies from South Windsor CT. They are very under the radar but make great speakers. They have been around for 30 years. They don't do trade shows or advertise. Seems that their business model is OEM work, custom home installations and home theater. Nevertheless their speakers are a very audiophile product. Use high end drivers some custom some off the shelf, great build quality and great sound.