The M21 has a very pretty two tone metal housing that could probably handle some nasty stepping-on of. The wire is the standard MEE wire. The plug is a right angled plug instead of the hockey stick plugs on the old line. They do protrude a bit from my ears, making it look like I have red bullets in my ears, but it’s no big deal.
The first album I tried the M21’s on is The Age of Rockets’ Hannah. It isn’t a particularly great mastered album—it’s brickwalled, like every other modern album—but it’s gentle music that has rather hard to render spectacularly by most headphones, with a few different instruments other than the standard guitar/drum/bass section. The album sounds pretty on the M21’s, but not perfect. The M21’s sound laid back in presentation. The bass is a tiny bit accentuated, but that’s what the standard MEE IEM sounds like. The mids are a bit veiled, and treble is rolled off. Soundstage is wide, but depth is lacking. The sound all in all is calm and pleasing, while not trying to impress anyone.
To review the M21’s, I’m using a NaNite N2, a DAP with a class A amp section, so while it isn’t as optimal as an actual external amp, it’ll do well enough. The N2 is already a warm player, so keep that in mind. Tracks are 320kbps. Tips used are the MEElectronics “Balanced” double flanges, which are my favorite provided tip. I’ll include a tip comparison at the end.
The bass of the M21, like every other MEElectronics IEM I’ve heard, (I haven’t heard the A151) is a bit north of neutral. It can get boomy at times where the music calls for tons of bass, but it generally is controlled and detailed. Like the M31, the bass emphasis is concentrated on the midbass, and doesn’t reach down low. It isn’t particularly offensive unlike the M31 can get, but it’s still there. The mids of the M21 aren’t exactly recessed or veiled, just sound a couple decibels south of neutral. They’re a tiny bit warmed up by the bass, though still manage to be plenty clear and accurate, especially for $35, which, considering MEElectronics’ claim to fame was a $20 IEM with HEEEEUUUUUUUGE bass, is a very impressive transition within a few years. Now, the treble of the M21 is average at best. It has no special attributes—it doesn’t sparkle, but it’s pleasant and detailed, extending decently high. While the treble isn’t special, it also doesn’t do anything obviously wrong, which is fantastic.
The soundstage of the M21 is wide, but not deep. It is about 2-3 feet wide and a feet deep to my ears, which may or may not be your experience, but you’re not the one with rulers in front of his face. The detail is very good on the M21, typical of MEElectronics IEM’s. Tone and timbre is decent overall. For the price of an M21, it’s hard to do better. It’s hard to do better even around $70 south of a certain Hifiman’s creation.
I shall be comparing tips, because there aren’t enough comparisons of tips around, and the M21’s are surprisingly transparent. Tips are an often overlooked part of an IEM, but it can really alter the sound of an IEM.
Single Flanged stock tip: These are your average tips, nothing special. The sound, however, is not a good indicator of how balanced the M21’s can sound. Bass is loose, mids are veiled, and treble is rolled off.
Balanced Double Flanged: These are probably the best tips you’re going to get stock. With these tips, they are, obviously, the most balanced. Compared to stock tips, the mids are much more coherent, bass is tighter, and treble isn’t as rolled off.
I lost the regular double flange tips so…moving on to aftermarkets!
Monster Foam Supertips: These tips set the mids free. The mids are actually forward using the Supertips, but can get grainy. The bass gets tighter too. Treble is a bit peaky though. Soundstage gets wider and has height.
Monster Gel Supertips: Yikes, there is some sibilance with these tips, and the treble appears from nowhere. Mids are much more balanced than with the foams, and bass is about flat. Soundstage kinda collapses though.
Ultimate Ears Silicon: The mids take a bit of a hit here in exchange for more treble, which gets slightly harsh. The bass is a bit north of neutral.
Comply Foam: The overall sound darkens. The bass has more impact, and begins to get boomy. Mids are as recessed as with the stock single flanges. Treble is veiled, and rather disappointing in general. Shame, I like foamies’ comfort.
Sony Hybrids: Bass is stronger than Complys’. The mids are about as recessed, and the treble is a bit less veiled than the Complys’. This is another unfortunate case because the Hybrids are really comfy.
Of the group, the foam Supertips and Balanced double flanges tie for my favorites, but considering the Supertips are really pricy, just stick with the Balanced double flanges. They are, as their name calls for, the most balanced tips for the M21.
I really like the M21’s even though it might not be apparent in the actual review. They are very balanced, but at the same time, give a nice kick in the bass. For $35, you can’t really do wrong with these. The Brainwavz M1’s are a tiny bit better, but at the cost of some durability and some style points. Overall, if you aren’t sure if you want something neutral, but you are sure don’t want something bassy, the M21’s are a serious IEM to consider.
The M21 retails for $35 for the non-mic version, while the mic’ed version is $40.