I like the idea of a speaker using a single full-range driver, requiring no crossover, so when Michael Tang of Michael Tang Audio emailed me, saying that one of the interesting products he's importing is the Japanese Feastrex driver, I made sure to check it out at SSI. There are two versions of this driver: the NF-5 ($2000), with uses an Alnico magnet, and the NF-5EX, with uses a field-coil magnet ($3000), requiring an external DC power supply. (Michael says he's used a car battery for this purpose.) The speaker he had on display was a floor-standing ported box; Michael says he's working on a transmission line enclosure of his own design. This one sounded most promising, with surprisingly good bass and a well-focused image.