I' going to do the best I can at explaining my dilemma. I have a Peavey 1516 can. It has 2 inputs in the back for full range and 2 inputs for bi-amp, hi and lo. I have been using the left full range input since I got it umpteen gillion years ago. It' been fine. I just replaced the speakers. The 15", 4ohm BW was replaced with a 15", 4ohm Eminence. The 2-8", 8ohm Peaveys were replaced with 2-8", 8ohm Celestians. Now I must use the bi-amp side. One cord to the lo and one cord to the high. I can no longer use the full range side to get all three speakers. Only the 8" come through using either of the 2 full range inputs! Why or how could this happen????? I did nothing but replace the speakers. Also, is it ok to use both channels on my Ampeg SVT7PRO for this one 4ohm cab??? I'm perplexed! Help me!