For those who don’t want to read, TLDR (short review) from Wife. On the highs “I didn’t think highs on speakers sounded different until I heard these” On lows, specifically Beasty Boys “Intergalactic” “Its like we were missing half the song!”

Detailed Review
High End
The detail and clarity for me on the highs blew me away. The SP-FS51s are known for being a bit rolled of on the high end but the R-41ms, which are fairly bright, didn’t bring out the detail like these did. “Hedwigs Theme” the seperation between different and similar instruments was greatly expanded. female vocals sound great. Taylor Swift, Betty. Halsey, Colors, all clear and natural. Cymbal crashes at high volumes will make you wince (like they should). Thirty Seconds to Mars “Battle of One” intro made me jump. Overall the high end came off raised, almost bright for me but probably because I’m coming from the rolled off Pioneers, and the detail was worth it. I’ve never found them fatiguing at any volume that isn’t fatiguing by nature.

Mids/Mid Bass
I’m not an audiophile, I listen for speed, impact, and natural male vocals. Male vocals, great. Bon Iver, Exile, from T Swifts folklore, excellent. Disturbed Sound of Silence, excellent. Also, plenty of speed and impact, similar in performance to the R-620s for liveliness down low. 10,000 fists, Disturbed beginning kick drum, great impact. I think the .5 of the 2.5 speaker design is a great addition, and helps with this.

Note* The 2.5 way system KLH employs here is very cool, with the lower woofer filtering out at 600Hz to allow the lower woofer to concentrate on deep and agile bass.

Bass
Surprisingly good. Its rated to 28Hz and I believe in the right conditions it reaches down that far. For most rock and non bass focused music you could probably go without a subwoofer. Beasty Boys, intergalactic, it follows ALL the way down, and it sounds like it gets to high 30’s with some authority. But bass focused songs that dig deep into the 20s and 30s and are looking for power, Super Bass, Nicki Minaj, or Astronaut in the Ocean, Masked Wolf, you’ll be missing some notes down low which is typical. The bass is good enough that while A-B ing these with the pioneers playing Intergalactic my wife, who was just humoring me even participating, turned and went “WOW. ITS LIKE WE WERE MISSING HALF THE SONG”

Conclusions
Build quality on this speaker looks great. The speakers look great as long as you’re into the big monolith with cool drivers aesthetic. The Kevlar woofers have a cool texture to them that looks good in varying light conditions. The black vinyl wrap is textured, which I like. Very cool that they give floor spikes at this price with discs for hardwood floors, and let them be adjustable. They also include rubber feet, but my hardwood floors aren’t level so the floor spikes with the floor protecting discs were a great addition (and they look so cool!). Binding posts, great. In the looks and build quality department my only knock would be that with the grills on, it is truly a featureless rectangle. You lose all points of interest, but if you’re going for low key maybe that’s a positive. They ship with port plugs, an excellent addition, as these are huge and likely need to be up against the wall for most. Having received them for free and been able to test them, I would now happily purchase them at the current asking price. I do hope to see a matching center in the same line in the future. I also hope they market these speakers more, I had never heard of them before winning them in this giveaway. I hope to leave this same review on KLHs amazon page and include pictures.

KLH customer service note. 3 times during this process I needed to contact customer service (not related to product issues). They were helpful and responsive within 24 hours every time, even giving me information on future product releases to help inform future purchases. Experience couldn’t have been better.