pairing 4 ohm speakers with 8 ohm speakers

Did you see my response in your other post?

Stacked Advents in parallel will be 4 ohm, and in series will be 16 ohm. Again, would you care to describe your connections?

Did you connect + and - of one speaker to the + and - of the other speaker? If so, that is parallel.

Raisedonrock, you out there? Just trying to help. I worked in the audio industry for over 20 years.

You are trying to do too much with too little. Since the
Luxman has pre-out jacks,you should get a separate amp to
drive the rear speakers. Another option is to get an AV
receiver that includes a separate amp for rear channel
operation. Why take the chance and fry your receiver?
Another problem is you will not be able to match the volume of
the front and rear if you use different speakers.

Sorry guys had a family matter to take care of.....My front speakers are in series. I crossed + and - on each speakers so the ohms wouldn't drop.