A driver large enough to produce low frequencies has too much mass to allow for the quick movement needed to produce higher frequencies. That's why a single driver is not used, except in things like portable radios. Devices that use a single driver will be compromised too much in either high or low frequencies relative to a good multi-driver design. Otherwise, everybody would be making them.
single versus multiple driver?
I have for years been thinking over the idea of a single driver easy load speaker with low powered set amps. I would love to take the plunge but am a little weary about the performance and risk. I listen to mostly classical,opera,jazz,older pop recordings and the like. I am presently using a pair of sounddynamics three way 300ti speaker and driving them B&K M200 amps. also bass is supported with the use of a Rel StrataIII sub. I am asking the question have any gone to single and been very disapointed and gone back to multiple drivers? I mean it really seems like a no brainer single speaker with no crossover should account to better sound? Thank you all and happy holiday.