Surprisingly, they sounded good at any genre. The DAC must be a good one. For the "surround", algorithms are not bad at all. The lows sounded more like a pro-audio sub rolling off at around 60hz. You need to add another sub if your looking for more weight. However if it's 60s & 70s classic rock, they contain minimal 60hz below frequencies so you're good! Overall they're cannot be compared to a home hi-fi 2 channel system BUT it'll still make you tap your feet once you crank the volume. It blooms at around 36-48 on the volume knob. It doesn't clip past 54. The highs sounded like they're tapered off in the 15khz however in a car setting where the tweeters are near the driver, you won't mind at all. With the proper treble adjustment, it's not harsh at all given whatever kind of music you throw.Mazda seems to be sound centric geared toward the front speakers, overall I think it sounds very good, but I listen to 60’s and 70’s classic rock so never really tested them with some good base! I will say tha Kashmir sounds pretty good though.
What is your volume level and treble setting?My tweeters were screechy/slightly distorted sounding at a certain high frequency pitch when I first got them. After about a month of break-in time this went away and now they sound great. Not uncommon for speakers to improve with time.