EP-830 isn't really comparable to the PL-30's .PL-30's have even been compared to the Shure's and likes.
Ive used EP-630 as well as 830. Both use the same drivers but the 830 has less of the boom boom bass which is in EP-630.
When I had the PL-30 ,I found it to be a big jump from the EP-630.It's sound signature is totally different with more of mid range and detailing and it has sound staging which is almost nil in the Creatives.
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REVIEW: Soundmagic PL-30 earphones & Fiio E3 amplifier..