That question is far too wide to get into in depth. But I have found that the drivers make a whole lot less difference than the system design. We tried several different manufacturers drivers in the Summa and in blind tests they were not found to be statistically different by 16 listeners. Although the price tags were an order of magnitude different and in unblind tests the results for the more expensive drivers were astounding. Kind of like "hearing" the color of the CD.