Originally Posted by
Jaywalk3r 
My CKM50 arrived today. The only other IEM I have for comparison is a Sennheiser CX 485, which I picked up for about $25 (MSRP is about $90, normal street price $30 - $45), so it's a reasonable comparison.
The CKM50 has not burned in yet. I'll just offer initial impressions for now, just in case that phenomenon is real.
Bass: The bass of the CKM50 is as overemphasized as I feared. This may be the greatest weakness of the CKM50, with respect to sound quality. It sounds as though a subwoofer is turned up WAY too loud. Bass heads rejoice; audiophiles beware. By comparison, the CX 485 also responds down below 20 Hz, but the level of the bass is more in line with the rest of the frequency range, so sounds much more natural.
Highs: Both the CKM50 and the CX 485 seem to have a V shaped frequency response, but the V is more exaggerated with the CKM50. While the its highs are not nearly as harsh as its bass is overemphasized, it does have slightly worse sibilance than the CX 485.
Mids: Due to it's deeper V shape, the mids sound more recessed on the CKM50 than the CX 485, but the effect isn't as bad as I anticipated.
Detail: The CKM50 has surprisingly good detail for being as bass heavy as it is. In fact, the excellent detail is easily its best feature. Here, the CX 485 is bested.
Imaging: The CKM50 seems to have a slightly wider soundstage than the CX 485, but the difference is minimal. Neither is bad nor great.
Overall sound: Despite the better detail and wider soundstage of the CKM50, the CX 485, with its flatter frequency response, wins here. It just sounds more natural.
Isolation: The CKM50 has better isolation, but it's much more difficult to get a good seal than with the CX 485. Hopefully this will change as I get used to them.
I'm not sure what to think of the cable of the CKM50. It's either too short or too long, depending on the configuration. I bought an armband and skin for my iPod Nano to make the best of it.
The CX 485 has an inline volume control, which can be used to eliminate line noise from the source. This is a significant advantage over the CKM50 (which is also a low resistance earphone) for me, but not necessarily for everyone. With the CKM50, I have to suffer through the line noise.
The two IEM have different strengths and weaknesses, and are in some ways complementary to each other. Overall, its just too early for me to say which I like better; it's close. But, I'm leaning towards the CX 485, due to it sounding more natural, which makes it sound good across more genres. If not for the bass of the CKM50, it would be no contest, but the extra bass just detracts so much from the overall sound. I'll use the CKM50 for 2-3 weeks, and then try the CX 485 again to see how I like it by comparison.
