I've been a long-time fan of AKG headphones. I recently bought the Hi-X55 headphones with high expectations. Unfortunately, they went back to the retailer in less than 24 hours. I thought their sound was terrible... overly etched, and extremely unpleasant to listen to. Th e only thing I can say, given the praise they seem to have received is that I received a defective pair.
Hey,
I recently had the chance to test out the Hi-X55, and I think I may have come up with a theory to explain your experience with the Hi-X55.
My first impression of the X55 is quite similar to yours. I found the headphones very detailed (but not overly etched) and I found them quite unpleasant to listen to. In fact, when I first tested it along with the X50 and X65, I liked the other 2 more.
However, when I returned to the store the second day and decided to give X55 another chance, I started to get X55's sound signature. X55 is harsh and there is no doubt about it, but in many ways, it is like that because it is designed to do so. X55's harshness is not a result of bad tuning (I actually find it quite well-tuned because there is still a 'lush' with all the sounds coming through it and its mid-range, especially with acapella vocals, is spot-on); its harshness results from the fact it is designed to be a mixing headphone.
Mixing headphones are not designed to make everything sound nicer (that's the job of Hi-fi headphones), at least according to my research. From what I know, X55 is designed to be "honest": it reveals problems in tracks that mixing engineers want to know, which is why it may not be great if you want it to be a day-to-day headphones for enjoying music. (btw, I also need to mention how X55 makes switching the sound source from an external DAC to laptop or phone DAC super observable.) With that said, X55 is also not trying to emulate the AKG sound that many have grown accustomed to. According to the owner of the store I went to, Austrian Audio's sound signature resembles more of AKG's earlier generation sound signature. The sound that most people associated with AKG is their later sound signature (not the newest though), so many would naturally find Austrian Audio to sound very different from AKG. But many of AKG's gene is still present. For instance, strings and orchestra sound great on Austrian Audio's headphones, similar to many AKG headphones. (I haven't tried this myself so I cannot confirm this claim.)
Anyway, in short, X55 is harsh because it is designed to sound critical, or maybe brutal, toward mixes. I find it personally still quite well-tuned. And after my first day, I will say I get accustomed to its sound. Coming from Grado and Sennheiser, X55 really feels like a new paradigm for listening to music.
Regardless, all it matters is what you enjoy the headphones or not so if X55 is too harsh for you, then so be it. I read your comment and I just wanted to share my thoughts since I had similar speculation. Anyway, I hope this helps and sorry for the long reply.