Both of M1 and M2 IEM can be considered base entry level as far as the pricing goes ($29.50 for the M1 and $59.50 for the M2). My first impression of the two IEMs is that they’re both likable. The M1 is a darker and bassier version, while the M2 is a more moderately balanced version. The IEM is tuned to work well with most of the mainstream music and recordings out there. There’s plenty of bass and midrange action, two of the crucial elements for most music genres. These IEMs are definitely not for treble lovers, nor for people looking for mind blowing technicalities. On the other hand, it makes a great entry level easy listening IEM.
The cable construction is quite unique. It looks like they uses very thin and flexible wires that’s wrapped with a soft and thin sleeving material. The result is a cable that’s softer than many other brands out there, and yet not as tangle prone as the Westone ES style cable. Despite being an low entry level IEM, I truly respect the fact that Brainwavs have put a lot of thought in the design aspect, resulting in a very comfortable ergonomics.
The M2 has a slightly different frequency balance than the M1. The bass is less prevalent, though it gives a better and tighter punch than the M1′s. The upper mid and low treble is also more forward, giving better presence on the vocals. You can say that the M2 is brighter than the M1, but still well in the realm of netural. In fact, I find the M2 to handle hot treble regions very well, as it stay out of any piercing treble and sibilance.
During long listening sessions, the impression that I have over the M1 is that it has a more laidback sound with a boomier bass. The M2 is more forward and engaging, has a better pace, and a tighter bass. To be frank, I think both IEMs have their own place. The M1 is prefferable for treble happy recordings with very forward vocals, where the M2 is better for cases when you want more vocal presence. The M1′s slightly boomy bass does bother me sometimes, and on those occassions I quickly switched to the M2. Neverthless, I do find the M1 to be better in the frequency balance than the ultra-famous Fischer Audio Eterna with its sea of bass and the un-engaging mids (dude, put your flame suit on!). True, the Eterna has a far more spacious soundstage and a smoother sound, but I still can’t get over the abundance of bass in the Eterna.
I also compared the M2 to the A-Jays Three and the popular Sennheiser CX300-II. The Jays have much tighter and powerful bass punch, but the midrange is not as engaging and there is too much upper treble presence that sounds too hot with too many recordings out there. The Sennheiser is generally smoother than the Brainwavs, but the midrange is less engaging and again the treble can be piercing with many mainstream recordings.
If you’ve noticed, the M2 is special for two things: an engaging midrange, while controlling the treble levels from any piercing highs. The treble levels is generally less than other IEMs in this price range. As a result, on first listen, the Brainwavs may seem to lack detail and/or unimpressive. But in reality, the treble level is just right for long term listening sessions, especially as modern recordings tend to be very hot in the treble. And you never feel that the M2 is dark or veiled either, as the forward upper mid always maintains a good vocal and instrument presence. The balance is subtle, but I highly regard such balanced presentation, as it can play a wide range of music without having any glaring weaknesses.