I got my Music Two today, along with the old review unit of the Pro100 re-made as a Music One.
While I might not be able to give in-depth comparisons just yet as I might have to get both refit (my right ear is actually really difficult to custom-fit; right now I get a good seal only if I let the silicone heat up and expand, and then wiggle it around in my ears for several minutes until I reach optimum fit, but it isn't Peter's fault), but with what I've been able to listen, I can give the following short comparisons between the M1 and M2, for people who want a brief guide:
- The M1 is a little warmer, mid-centric, and less detailed, and definitely can't do bass the same way the woofer on the M2 delivers bass. Overall bass shelf is a little lower in quantity.
- The M2 feels a little brighter up top, and because the upper mids are not recessed at all, the M2 sounds more detailed and bright, a little sharper sounding.
- The M1 is more of a relaxed earphone with a little bit of bass roll-off, whereas the M2 has more of a "Fletcher-Munson U-shaped lift", giving fully extended bass, slightly more delicate timbre, and a fair bit more detail. Thus, you'll be able to "hear more" at lower volume with the M2.
- The M2's dedicated woofer enables the M2 to get a cleaner, more textured output in the bass than the M1. I find that the M1's driver has its limitations. It can at times distort the bass and I can detect some distortion with the M1, whereas the M2 has more headroom to get the job done cleanly.
- The slightly more delicate timbre of the M2 helps the M2 sound a little more refined than the M1, but the more relaxed nature of the M1 somewhat equalizes things.
- While neither has that huge center image of the Harmony, the linearity of the stereo image is decent with both the M1 and M2 are good, as the M1 is a full-range single driver model, while the M2 is essentially a single driver unit that happens to have a woofer (cut fairly low) attached to its bottom end. I find that phase non-linearity affects the makeup of the stereo image quite a bit more from the midrange upwards, affecting upper midrange and treble quite a bit, as humans are very sensitive in that area and thus respond to directional cues better. So, both models perform decently, a bit better than the Noble 4C than I've been using recently as well.
- However, as it takes a long time for me to get into the optimum L/R fit, I'm unsure of how large and accurate the center image is on the M1 and M2 relative to one another. Get the insertion depth and angle right, and the well-formed image creates a nice, relatively large suspension of vocals right in front of you. Don't get it right, and you get that tiny "head space" type of sound that many people dislike.
- For the price, I'm astounded by how well the M1 performs. It's just so well-rounded. I heard an ACS T3 today, and wasn't nearly as impressed by it as I was even with the M1's demo unit. It extends well, and has a very natural sound signature. The natural warmth of the driver carries over well. Anyone who desires a little more brightness can just use an amplifier with greater OI, or use an in-line resistance adapter.
- For personal listening, I find that the M1 is a better choice than the Pro100, and would encourage anyone who wants to use an entry-level CIEM just for personal listening (and the occasional stage monitoring) to get the Music One. The Pro100 has added warmth to reduce listener fatigue, but unless you intend on listening for 8+ hours a day, the Music One should be okay if you listen to music at reasonable volumes.
- For that extra little bit of oomph in the bass, cleaner output, and more detailing, the M2 would be a step up. I find that the soundstage appears to be wider, but that might be more of an apparent psychoacoustic effect of the slight U-shaped lift that the M2 has over the M1, rather than a big increase in overall extension on both ends. Nevertheless, I'd say most genres of music stand to benefit from the presentation of the M2, unless you're specifically looking for that slightly more laid-back, mellow tuning of the M1.
Whoa, that was actually more than I intended to write, and I actually think I covered a fair bit there, but perhaps not in the clearest manner.