I would like to ask any knowledgeable guys out there a couple of questions on the new 670, does it have a sampling function, to input new sounds via a mic, the casio 7600 appears to have this, also the 670 seems only to have a single pair of 12.5 cm speakers, would these be enough to handle the 15 watt output without distortion the casio 7600 has three pairs for only 7 watts, I am trying to decide which model to upgrade to , Casio or Yamaha any help most welcome.