Receivers are sold only in America. The Japanese refer to them as "tuner/amps". Makers of receivers do not incorporate circuit design found in amplifiers. A huge torroidal transformer, transistor outputs, dual power supplies, are all features found in amplifiers and not found in receivers. Amplifiers can drive almost any speaker, regardless of impedance. Receivers must have discrete (transistor as opposed to an IC) outputs in order to drive box speakers which are not very efficient. ANY speaker will sound hugely better when driven by an amplifier. Any speaker will sound more hugely improved when driven by a 200w/ch amplfier. The air, depth and imaging will be amazing! P.