My score seems negative but do not be put off. I have already sold my pair of westone 4s as I personally do not find them to be particularly enjoyable. However, up till now, they are still the best pair of universal iems I have used. The sound is pretty balanced, though not dead accurate. The mids are slighlty forward and warm, being very enjoyable. The treble is clear and extended yet smooth and the bass is well extended though not the most impactful. You will probably be asking me why I disliked them then. The reason is that I believe that they just cannot compare to headphones such as the hd650, k701s which are cheaper than them. I find them especially lacking in the areas of soundstage and instrument "air". I therefore made the decsision to sell them and purchase more headphones. (Currently using LCD 2.2, K701 and Hifiman He-4 soon) For mobile use, I am now using a re-shelled tf10 (soon to be UERMs) which I find to be better than the westone 4s imo. I would strongly urge anyone looking at the westone 4s to consider full customs such as the um mage, miracle, uerms, etc. They are more expensive but offer a significantly better sounds, especially with regards to soundstage in my experience.

 

Just got my rev 2s a few weeks ago. After pretty extensive comparison with my previous rev 1s, I prefer the rev 2s for almost any music. The overall fidelity is just slightly better and the upper mids and treble, slightly more pronounced, though imo a bit of midrange density is sacrificed. What makes me prefer the rev2s is the soundstage more than anything else. In the rev1s, I really disliked the sound stage as I found it to be really disjointed, presenting sound in three columns, left, centre and right with "walls" between each column. In the new rev 2s, while the soundstage is not expansive like a hd800, it is a very nice, coherent semicircle presented in front of the listener and I really like this change, hence my preference for the rev 2s.
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