I also have the LSi25 speakers. I was using just my Marantz SR7010 (140wpc x 2 into 8ohm) to push them. I thought at my age I would be happy with that small amount of power. Like i said 140wpc is great into 2 speakers but when devided into the 5 channels of a surround, it is only like 60wpc, and that's not good for me or speakers that love power. I was using the Marantz in 2 channel mode they did very good but after a few uses in 5 channel mode my receiver would go into safety mode. I tried everything with the help from Marantz and Polk. Then I finally talked to the right person and he knew what I had suspected all along. I was not giving the Polks what they crave, POWER, and a lot of it. I had smoked the crossover in the left speaker. He sent me both sides and explained that he guaranteed that the right one was getting ready to go out because both sides had been starved of power. I didn't believe him but it went out within a week..lol. Anyhow to make this long response a little longer, I replaced both crossovers but at the same time I purchased a new Emotiva XPA3 that pushes 275wpc into 8ohms and 375wpc into 4ohms. These speakers are now some of the best sounding speakers I have ever owned and I have owned several nice speakers in my 37 years of buying and selling audio equipment. I hope this helps.