So I got my pair of KH 120 II and almost had a heart attack. That's because my parents brought them from Europe in their luggage (and complained a lot, as these are not exactly small or light), and once I set them up at the office at home, the left one had a strange noise coming out of the tweeter. I thought it was a ground loop, so lifted the ground through the switch and nothing. I disconnected the XLR and still the noise was coming out of the tweeter with the speaker idle. I even swapped power cords and nothing.
I don't know if warranty was going to cover a defective unit in another country, it was a risk I took when I decided to buy it, but I was not expecting to use it so soon...
Then I saw behind this speaker and there it was: my Wi-Fi router on the table, a TP-Link Deco. I moved it some 20 cm to the side, right behind the monitor and between both speakers, and instant relief: the noise was 100% gone.
Funny thing is that the former KH 80 DSP in the same spot never had any issues. So I guess the 120s are more sensitive to Wi-Fi interference?
Anyway I listened to them and compared to my 80s. How do they differ? On paper the tweeter of the 120s are a tiny little more linear, and the dispersion very similar (that is, excellent). The elephant in the room is the bass extension: 53 x 41 Hz in -6dB makes a big difference. Still no extension to subbass territory, but nonetheless a healthy bass comes from the speakers. Also they sound less strained when playing medium-loud, naturally and expected.
So my 80s are going up for sale locally soon, and I will always remember the scare those 120s gave me lol.
Since a post is worthless without pictures here is one. The 80s are covered on the right.
View attachment 377395