Test: 2 identical tempest adire alignments powered by two identical 250W plate amps. link 2nd plate amp daisy chained to another resulted in a noticeable loss in decibels and loss in SQ. The Parts Express 300-974 amp manual says "full range" mono pre amp out, but in small parenthesis it says (20-20khz). Therefore during 15-20hz test tones the 2nd sub receives barely anything at all while the 1st sub shines with authority. Not to mention the sound quality of the 2nd daisy chained sub is noticeable worse when the crossover setting is adjusted high, I couldn't imagine anyone else running their plate amps daisy chained. The sound from the 2nd amp has more highs than the first sub and sounds muffled while lacking deep bass. Both amp settings are identical and location is mirrored in rectangular room, and I swapped the amps and messed with 3 different subwoofer interconnects and had the same conclusions. I guess I'm going to have to go Y-splitter because of the pre amp outs on the amps. Unless of course someone can explain what's going on. When I first fired up the subs I was like "What's going on! are these amps different?" The bass stage actually shifted to side of the 2nd sub as it appeared to play more muffled upper bass than the first sub therefore drawing attention to itself. Of course to the average ear the subs would be OK as I had to concentrate a bit to figure things out. I wonder if others, maybe even the AVA250 has a similar problem with pre-outs? Anyone see if their pre-outs are full range by seeing if a 15hz test tone will pass through or playing full range signals through their subwoofers and focusing on vocals like I did? Oh well, I hope a Y-splitter will solve the problem and not degrade SQ. Guess it's off the the rat shack tomorrow.