Many speakers which are designated as 8 ohm speakers actually have an impedance as low as 3 ohms at some frequencies.
In any case, the impedance has NOTHING to do with the quality or the performance of the speakers.
Low impedance speakers are usually not going to work well with the typical AVR because they almost all have really crappy power supplies that cannot supply the peak current needed to drive that kind of speaker, and distortion results.
Low impedance speakers need to be driven by an amplifier that has a very good power supply and that usually means an expensive amplifier.
Originally Posted by Newbie01
Let us not forget that allot of speakers are listed as x ohm nominal ...etc... There are no true standards here. Some list 4 ohm if the speakers lowest rating dips into the 4 ohms. Since 4 is the lowest that is really listed some speakers can actually be 2 ohm...
Some "8 ohm" speakers are actually dip to 4 ohms. You have to really see the impedance charts to truely tell ohm.