I am pretty new to the amp/receiver/speakers community, and I have a question I hope doesn't embarrass me too much. I have 2 receivers right now. One is a Pioneer SX-650. The other is a Marantz 2230. I don't need to play them both super loud, but when I do turn up the volume, I notice the Pioneer can go much louder much more quickly. For example, turning the volume on the Pioneer to about 25% on the volume knob, is about as loud as putting the Marantz to about 50% on its volume knob. For testing purposes I have played both receivers through a pair of Klipsch SF2 speakers. I don't know enough about watts and power and their impact on volume. Could one of you good people explain this simply? I am trying to determine if this is an expected result from these 2 receivers, or if the Marantz has some sort of problem that might be affecting the volume.