What is the difference between 2-way and 3-way car speakers?

What is the difference between 6inch/16cm speakers and 9inch/24cm speakers?

• I'm not that knowledgeable about car audio -I have 2 6inch/16cm sony xplod 2way speakers, and i have no idea what else i have to buy or where the speakers go, i'm not buying a sub im just going to buy another 2 speakers and an amp

• Answer:

  A bigger speaker size does not mean it will be louder, loudness (SPL output or dB levels) all depends on the speaker's sensitivity and power handling (watts RMS). It's much easier to get the same sizes, or smaller and buy an adapter. try http://www.crutchfield.com, go into the speaker section, there should be a vehicle fitting guide... enter your vehicle information into the site, and it should tell you what speakers will fit in. You can also buy any sized speakers and build a custom mounting location. but this takes alot more work. 9 inches isn't really a standard size in car audio, and neither is 6 inch.... there's 6 1/2 inches, and the oversized 6 3/4. no big difference between sizes, but usually the bigger the speaker and wider the frequency response.