I'm not sure!
Klipsch definitely
earned a bad rap for the harshness of their earlier speakers!
At the same time they were successful because the horn resolved some other problems speaker manufactures were wrestling with in the 60's & 70's (mainly SPL/efficiency/power concerns).
Subjectively, I believe they have been a good value for HT speakers for a while, and find there new RP series (among affordable speakers by Klipsch) to be the first speaker they have made that I am entirely comfortable using for a music speaker as well. The problem has always gone to the horn design and the way it "throws" sound at you. I believe the current Reference Premiere Series (such as the RP-160m) has refined the horn to a level where it is no longer harsh or even bright. Most notably, I can toe this speaker in so it is pointed straight at my ears! If I do this with my RF-82 ii's they will be too bright for me.
With the RP series, it has taken me a while to understand what I am hearing and correctly communicate it, and I'm not sure I really
know what I'm saying, but this is my latest take on it:
They are still a great HT speaker. What makes them a great HT speaker is the level of "impactfulness"/micro-dynamics/detail which I believe are directly related to the horn design. The attacks of sounds are very crisp and clear. This is great for HT because it gives a heightened sensation of the tense "pin drop" that sets off events in a suspenseful. The Klipsch will stand the hair on the back of my neck up like no others. It is also great for clarity of dialog!
Yet, they are a wonderful music speaker (IMHO). The horn effect (impactfulness, micro-dynamics/detail) is great for a lot of music where the attacks of notes are emphasized. Percussive sounds thrive. For most rock music I find this not just acceptable, but great! However, in the context of acoustic music, this same sensation come across as the sounds being "vivid" and I think that is the perfect word for it! It is far from a bad sound! As a visual analogy, it is kind of like looking through lenses with a very slight amber tint (which increase visual contrast). It can even be a little addictive! For electric guitar, this sounds natural enough (because there are many variables which could allow this to be exactly the original sound),but for something like vibrato on a violin, the vibrato can be a bit too vivid to be natural (especially if the musician was already making the vibrato strong)!
As I said above, I am totally comfortable using these speakers for music this effect is not a problem for me, only on certain content will I notice it, and when I do notice it I think "Wow, that was cool!", but if I do a reality check I realize it probably isn't perfectly true to the recording! Just like the amber lenses, you forget you have them on, but every once in a while something will visually "pop" beyond what is normal. I have yet to notice a place where it sounds "bad".
So, "it is what it is". For me it is entirely acceptable, and often an enhancement I am glad to have. For others it is the best rock speaker ever, and I totally can relate to that! I, personally, have a harder time relating to someone who says (of he RP series) "they outright suck", but I can certainly understand it as the reality that we are individuals (and not a true "hive mind" - though I still like the image). I know there are speakers out there that I discern as having problems, but other experienced "audio geeks" don't notice or it doesn't bother them.
For me, Klipsch has improved enough that I think they no longer deserve the harsher
criticisms they receive, but even if everyone perceived as I do, it would take years to shake their past reputation. Furthermore, I can imagine someone (such as myself years ago) involuntarily cringing when Klipsch horns are pointing at them, and I bet that is enough to tense the eardrum so they would not experience sound quality!