I know that with most Klipsch speakers a flea powered amp will make them sing but with the larger woofers they still need power to move air. I have two pair of Infinity SM 150 and 155 with 102bd efficiency but the low power amps and receivers barely move the woofers, whereas with the big power amps they come to life. I would assume that would be the caase with La Scalas, Corwalls or whatever as well....no?