As long as your receiver can drive both 6 and 8 ohm speakers you will be fine. You will compensate for the impedance difference when you set the speaker levels - if you used different amps with different gains, it would be a different situation.
The issue with mixing speakers has more to do with the sonics of the different speakers, which has already been mentioned. The goal is a seamless soundstage throughout the channels, the most important being the fronts (LF, C, & RF). The rears are less important but they do work best if they match the fronts as well.
Hope this helps. :o)
The issue with mixing speakers has more to do with the sonics of the different speakers, which has already been mentioned. The goal is a seamless soundstage throughout the channels, the most important being the fronts (LF, C, & RF). The rears are less important but they do work best if they match the fronts as well.
Hope this helps. :o)