Two–Way Versus Multi-Way Loudspeakers

The combination of driver diameter versus higher frequency dispersion explained in our previous blog post is an immutable law of physics. It means speaker designers always have to contend with it in their designs and the truth is, every design choice made involves some sort of compromise in performance. You can build a single driver that will reproduce a reasonable frequency range but you’ll have to be right on axis to hear the higher frequencies it produces. And its total frequency range will be limited at the extremes by choosing to make it this way. Therefore, designers make two, three, four, and more multi-way speakers to overcome major issues in making a single driver full range system. The following doesn’t necessarily apply to electrostatic, planar or other, more exotic speaker designs.
 

Some of the upsides of a well-designed multi-way speaker include:
  • Better dispersion for mid-range and high frequencies theoretically resulting in a broader “sweet spot” and better imaging/soundstage creation
  • Broader overall frequency response; deeper lows and higher highs, somewhat dependent on system and driver design and size
  • “Faster” more accurate response to higher frequency signals. To reproduce 15 kHz the driver diaphragm must move back and forth 15,000 times in one second. Try achieving that with low distortion using a 6.5, 8, or 10-inch cone.
  • Drivers can be optimized for the specific frequency range they’re going to reproduce.

 

Some of the downsides of multiway speaker designs include
  • More expensive to buy compared to equivalent quality 2-way models
  • May be designed with complex, expensive, power wasting crossover networks
  • Usually are larger and may require more power to drive properly than simpler 2-way models

More next time…