Yh Petrucci's guitar is mahogony block, alder wings and a maple top. Mostly his guitars are alder or Basswood, but he decided on the mahogony block to compensate for the chambers carved into the alder. (this is john petrucci's words not mine before anyone says it's a load of c**p lol.) The thing that confused me was how positioning diferent woods on a guitar body can achieve different tones. Why does a *insert your wood here* sound different as a laminated top, compared to it being a tone block or wings etc? I'd really like professional opinions here or people who think they have a good idea. I've posted in other forums and it attracts so many know it alls who know naff all and take the p*ss because it's not "good enough" for them and the best equipment in the world is only equipment "they" play. Sorry to rant on but I'd really like a serious debate etc. and I'm sure you know the people I'm on about :D