Buy and large for me "SLAM" is a HiFi or pro-audio support thing. What I mean is, very little acoustic live music ever produces real "SLAM" unless it is of an electrified genre. That said, I think it is a matter of taste for the music reproduction listener and yes it is a matter of amp AND speaker synergy to produce the physical wallop you desire. For me, that characteristic is way down the list of sonic requirements, below timbre, tone colour, texture, and transparency, just to name a few. But I don't mean to rain on your parade, if that is a compelling element to you at this point.I would only caution that to accomplish this, you may well compromise other more subtle aspects that could prove to be more satisfying in the overall context of a musical performance (even in a hard rock type format).
Happy Listening!
Happy Listening!