Im running a 4 channel eclipse ea4200 bridged on HZ HSK 165s as of saturday. These need 125 watts and are getting 150 watts per side, replacing Eclipse SC 8362s that could take 100 watts per side and got 60 off of two of the channels. Just saying from initial impressions with the head unit's EQ flat just like it was on the eclipses, if you're looking for a sharp, bright 'attack' on every instrument, look elsewhere. I can actually hear the finger pluck the string of the guitar less sharpy on these than I did on my eclipses. But mid bass is noticably better. These blend with my sub with alot less tweaking and experimenting than the eclipses did, and with ALOT less blending between the crossover points of the amp. Before I had to play my mids at about 65-70 HZ and the sub at 80-85, now I can set both the low pass and high pass at a bout 75-80 and the bass stays clean and feels like it's coming from up front.
Seems like the SC 8362s had a 'peakier' frequency response where things somewhere in the mid range got very exciting but then they died off near the crossover points. The HZ mids seem to play everything in a more natural mix and have a flatter frequency response at the extremes of the frequency ranges. Meanwhile some other mids will emphasize the meat and potatos somewhere in the mid range where the sounds that make it real for most people are found, but then they die off near the x-over points.
Cymbols and other high frequency sounds are more full-bodied and less airy. Guitar has a stronger body and reverbration that it used to. Piano is more pronounced and distinct with more fullness and less scratchiness. Snare and kick drums have more depth and body now than they used to. I can crank the volume now and neither the vocals nor anything else gets tinny or nasally to the point where it hurts my ears.
IF you want to hear a nice, sharp attack on every note these won't do it, not without some tuning and not in a conventional configuration with a door mounted mid and sail panel mounted tweet. What you'll get is a smoother, more natural blend of the music with really good imaging where you can differentiate everything but no specific frequency consistently jumps out at you. Vocals also seem a bit more subdued but again I attribute this to the fact that mid bass and upper midrange close to the crossover point are so much better that vocals don't jump out at me like they did with the eclipses. Before it almost sounded like a solo guitarist was actually sitting in front of his instrument until I tweaked the limited EQ on the head unit to get the right imaging.
Id say Hertz does a little bit better in just about every frequency range than most speakers I've heard but if certain frequencies being overpronounced are actually what make your music more real for you consider something else. Seems like this speaker is about getting as loud as possibible with an even frequency response and zero distortion. Perfect for an SQ setup with just enough sub but no more, but if I was trying to overcome a REALLY strong substage Id go for something that put a little more emphasis in the midrange. IF you like smooth and even, it's all good. If you like sharp and bright, not so good.