Pros: Clarity and resolution. Lots of detail. Good soundstage with well presented imaging. Mostly neutral timbre, slight focus in mids; good vocals. Build.
Cons: Not always the best fit and seal. Recessed treble; high frequencies lack "sparkle." Slight spike in uppermids. Bass can sound too light for some.
The Denon AH C250 - it's like a pretty gold ring that doesn't fit every finger.
Yes, it's good. Quite good. Yet the likability is highly dependant on what it's best at and what it doesn't do great.
This particular IEM, while mostly neutral were it not for some noticeable lack of energy in the upper notes, is geared towards audiophiles rather than the pro audio crowd. Harsh sibilance is near non-existent, as the treble has lost some of its glitter and energy - usually something pretty common amongst many IEMs. Transients suffer a little, lacking the right snap, click or pop. Sometimes it's a bad thing to be too careful. But it's never as bad as stubbing a toe.
The midrange is where the AH C250 shines. Singers are clear and prominent, with a decent amount of life in them. Sometimes the upper mids tend to be a little strong, but never aggressive or metallic. There is some muddiness in the lower mids, but mostly seen as some lack of clarity rather than humming or unpleasant distortions.
Bass could be better, but it's there. Definitely, these are not IEMs meant for electronic music or hip-hop. They lack punch and power. The bass is neutral and unflattering, and goes very deep, presenting low frequency details in a mostly clean manner. However, the bass is far from musical, and leaves certain songs and genres feeling a little underpresented.
Honestly, these headphones do best with oldies. Lots of lyrics. Also pleasant with mellow forms of instrumental jazz and funk.
The soundstage is admirably spacey for a single driver balanced armature IEM. While IEMs are rarely large sounding or very "around the head," the soundstage is breathable; excels more at depth than width. The stereo image is well presented with limited smudging and only moderate overlapping. Positions and movements are cleanly and neatly presented. The 3D illusion is well created and easy to interpret. Nice for live recordings. Even binaural material plays well.
Resolution and clarity are another strong point. Not considering the generally standard limitations of IEMs, and not looking too deeply into the slight muddiness within the lower mids, the AH C250 presents detail and microscopic nuances quite cleanly. Not exactly the best at picking up interesting sonic effects and dynamics, but with presenting fine details and the normally unnoticed, music tends to sound pretty exposed and "raw" on these. High quality recordings play well and thoroughly. There isn't much of a requirement for amping, either. You can get away with a weaker amp or even no amp at all. I do, however, recommend a decent source to compliment this IEM's revealing nature.
As for the build, I have no complaints. The materials appear to be of high quality, and reliability and durability do not concern me. The cable, while not detachable, is seemingly tangle-resistant, yet isn't too stiff for on the go usage. I appreciate the built-in microphone, which is of average quality. The real concerns are with the fit. Comfort and seal aren't best, particularly because I find that in spite of the many sizes of ear tips included, there is still some wobbling and "movement noise" when I have to get up and move around quickly. Maybe it's just my ears, but I have felt better fits elsewhere. It's a winner for style points, but for a product that is most judged on sound, this hardly has any real impact on its value.
Speaking of value, it could do a little better with pricing - it's overpriced in Canada, for example - but what it does best, plus how well it is built, makes it not a bad purchase by any means. I do feel that there is better weight for the dollar in this tier bracket of IEMs.
In retrospect, the Denon AH C250 is a respectable intro to high res audio capable products, and can be enjoyed by consumers looking to experience a recording in a mostly transparent, clean-cut presentation with little to no fatigue at the expense of some musicality and energy. It has a mellow sound signature that would not appeal to everyone, but does an excellent job presenting vocals as well as revealing fine acoustic details, whether intentional by artists or hidden within a faulty recording.
Worth the purchase for its strengths.