2-way speaker with best bass

The cone of a loudspeaker "breaks up" well below the frequency where it quits making sound. "Breaks up" means that different parts of the cone vibrate at frequencies that have more to do with the cone's mechanical caracteristics than the music. In other words, noise. This sound is undesirable, and should be eliminated by use of an electrical crossover of one kind or another. Output at the desired music frequencies aproaching breakup also exhibits large dips and spikes, also undesirable.

Some cone drivers are better than others. Exceptionally good ones are called "full range". They experience cone breakup too, but the spurious sound is of a pleasant nature that some people like.

These discussions of how low a frequency can be reproduced always lack one important detail...How loud? Earphones, with tiny "cones" can reproduce the lowest frequency, but at a volume so low that they need to be on the ear to be heard. Small loudspeakers can likewise deliver excellent LF performance, but not at a reasonable volume, particularly in view of the human ear's roll-off at low frequency. Large cone drivers can deliver LF at a volume which is realistic, and without the extreme distortion-producing cone excursion typical of small-driver systems trying for the lowest octave.