You see, I am a big fan of tight, fast, punchy bass. Bass that leaves you shuddering from the first hit, and then escapes like a bandit before you can react. I do NOT like warm, fuzzy, lazy-ass, boomy, wooly, loosie-goosie, overblown, ghetto-car-audio-that-just-rattles-license-plate-frames bass that can't decide whether it's coming or going. So along those lines, I just want to say that the HD 215 exhibits some of the best bass characteristics that I've come across in a long time. In simplisitic terms, the HD 205 is going to sound like it has more bass. But the devil is in the details here...

However, I did hear what sounded like a sharp tonal transition in the upper mid-bass region - right at the point where mid-bass tends to transition into mids in a lot of modern music. I believe that bowei006 touched on this in his review, and I'd like to add my impression here.And whereas the HD 428's lush highs tend to drop out and roll-off sooner, the HD 215's top end is much brighter and extends higher (albeit exhibiting sibilance on occasion). Mids are squarely neutral but smooth - are neither irritatingly forward nor disappointingly recessed - and extend nicely and consistently into the highs.

If you are an audiophile in the market for a pair of closed circumaurals for casual listening on-the-go, that can take a beating and sound alright doing it, I would consider these a viable option. We used the HD 205 II headphones in conjunction with a Toshiba Qosmio X505-Q880 laptop (with Dolby Home Theater technology), an Onkyo TX-L5 receiver, and the Apple iPod Classic, Creative Zen: Vision M, and Zune HD MP3 players. With a 32-ohm impedance level, it takes little power to drive these headphones, so they're easy on the batteries in portable devices.

Sennheiser HD 205 - Technical Overview

And while I would not describe the sound as warm or rich, I wouldn't exactly label it as being clinical either. It's very much middle-of-the-road, neither truly flattering, nor giving offense. And it is precisely because of this balance that the HD 215's mids are unexpectedly pleasant on multiple levels.