Back in the sixties and possibly into the mid seventies, JBL and Stephens-Trusonic produced what they called extended range or full range drivers. Both used an aluminum dust cap for the mids and some of the lower highs. For optimum performance, they were designed to mate with a tweeter, but on their own they still sounded very good. No x-overs, not even a capacitor. I believe there were 8,12,and 15 inch versions. They come up on E-bay occasionally, but the aluminum dust caps are often dented. I once had a pair of the Stephens 8 inch variant, and it was a very well made speaker.
Single driver vs traditional 3 way loudspeakers
What you prefer , single driver , no crossover, full range loudspeakers powered by low power SAT or traditional 2-3 way design ?