I have an old 5.1 receiver that is 85w per channel ( no biwire or biamp settings ) that has an all channel stereo setting. I also have two yamaha ns-777 which are rated 100w nominal and 250w max. Now can I wire both front left/back left to the left speaker and so with the right and set the reciever always on "All Channels stereo" and get the max power without problems? I do not need or want 5.1 in this setup. If it is possible to do so, will I loose quality of sound or are there any downsides?