I received a pair of KH 120 II's today. I spent a few hours comparing them to a pair of KH 150's.
It was easy to match them in terms of level and the frequency switches. I do not think that this was an accident. I think that Neumann audio engineers very deliberately work to make their monitors have that family sound. (which is flat frequency response with low distortion).
I should note that I am a strong supporter of measurements and science and am always skeptical of subjective evaluations. I think this comes from my prior life as a psychologist.
Any way ------ this is my initial impression, yet to be confirmed with more listening comparison.
I cannot tell a difference between the KH 150's and KH 120 II's - with the exception of bass in the lowest octave.
I should also note that (except for EDM, which I do not listen to), it is a very rare pop, country or hip hop song that has any content down there. Producers very deliberately cutoff those bottom frequencies, even in the very unusual circumstance that the recording has any music down that low.
I had to very deliberately search for songs with content at a frequency low enough to distinguish the KH 150's from the KH 120 II's.
I will also be comparing the KH 120 II's to my KH 120's.
Here is a size comparison between a KH 120 II (left) and a KH 120.
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