Got my ie300 and not that impressed.
Im coming directly from the CX300S which I recently picked up and wanted to upgrade to ie300.
My experience with over-ear headphones in similar price brackets, €50 vs €300 msrp, is that there is significant step up performance with higher end options e.g HD650/600.
IE 300 definitely better than cx300s but they surprisingly very similar overall with marginal improvement in most areas.
Its my first time with higher-end IEM and greater diminishing returns compared to over ears might be something to be expected.
The HD650/600 are also probably the biggest gems of the headphone world, so it is a tough thing to compare to, maybe ie900 couldgive the kind of sound quality I was hoping, too expensive for me though.
Build quality, comfort etc. are also all really good, as to be expected from sennheiser, which is obviously an extremely important consideration.
Maybe some chinese IEMs in similar price range could impress me more in terms sound quality, a lot seem to think so, but build quality, QA, comfort etc. are things that I feel may not be guaranteed with those so didn't want to bother taking the gamble.
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ok little update, I removed the foam in the tips and the change was quite positive. I notice with these senn IEMs the smoothness of the treble compared to full size hps, it is expected a tiny, light driver would excell at higher frequencies. IE 300 treble is incredibly clean and smooth, but there was some hashiness or grain to it and this seems to have been related to the foam. Without foam Ie300 high treble is really just exceptional, havent heard anything like it, though the high treble range does not typical contain much important musical information, but it is area that significantly impact fatigue, glare, harshness and so on, something that is subtle but obviously very important.
I also notice they do handle higher SPL very well, without sounding compressed or muddy, I listen at lower volumes so not really a benefit to me but worth mentioning.
I still find bass and midrange is lacking some texture and meat, not the most realistic timbre, but the speed/dynamics are excellent.
I need to play around with tips more, it could be simple seal or fit issue.