The MJ2 is rated at 32 ohms and 120dB which is pretty sensitive for a portable headphone. As such you won’t have too many issues getting good volume on moderate sources, amps and even smartphones. I am pretty sure that was the aim from Mitchell & Johnson given the short cable, efficient rating and neat and tidy closed form factor.
Volume wise it is a step up from most IEMs but not hugely so with the DX200 sitting happily at 100/150, the FiiO X5iii at 75/120 and the Sony PCM-D100 at 2-3/10 (which is rather normal for the powerful Sony). As an additional bonus, the MJ2 is surprisingly resistant to background noise and hiss despite its sensitivity ratings.
The main benefit from a better source or amp with the MJ2 is the relative levels of clarity and control. In short, they get a lot better when you throw a good amp at it.
It does not have to be a powerful amp, just one with a good quality signal. A poor amp will smooth over the details a little and allow bass control to get a little loose in comparison to say the iBasso Dx200 and Sony’s PCM-D100’s neutral but tighter pairing at a DAP level and ALO Audio’s V5’s smooth mids performance Lear’s FSM-02 v2’s Class A dynamics at an amp level.
For some that smoothing actually might be ideal for laid back listening but you won’t be getting the most out of the MJ2 so I would grab a smartphone really as a backup option.
Source and amp selection for the MJ2 sees some minor variation in tonal presentation but nothing radical or eye opening. It’s a fairly sensitive and easy to drive headphone but not one which will massively scale. A good amp, however, will tighten up its signature and as mentioned a weaker amp, such as a smartphone amp does seem to loosen the bass response and soften the attack and top end.
For example, the ZTE Axon 7 android smartphone packs an AK4490 DAC inside which is a popular DAC known for its musical qualities but coupled with an average amp inside the resolving capability of this pairing is a bit lower and softens up the MJ2 considerably to the point you might be thinking it is a nice warm pleasant headphone but not razor sharp in control.
What you are looking for
Once you start working with more competent source and amps then the control comes in and everything tightens up. The most important thing for me with the MJ2 is that the pairing must be able to give you a high level of resolution, transient response capability as well as offering a presentation that is incredibly accurate with spatial cues and bringing out the MJ2’s excellent imaging potential.
DAPs such as the FiiO X7, iBasso DX200, and Sony PCM-D100 fit the bill and come across actually as being very similar in their sound when paired with the MJ2. The only key difference for me is the D100 being slightly brighter in the mids and treble and having a more forward vocal staging quality than the more reference like or neutral sounding DX200. Otherwise, both offer a very balanced tonal quality with the MJ2 with plenty of detail and excellent dynamics.
The X7, on the other hand, depends entirely on the amp used and for me, the AM3 is the most balanced out of the AM1, 2 and 5 though those looking for the ultimate reference pairing might find is slightly laid back and smooth sounding in comparison to the more neutral DX200 and PCM-D100. Outside of Sony’s proprietary sigma-delta DAC being built in-house the common theme with the X7 and DX200 is a super nice ES9018/28 DAC implementation. The MJ2 really does welcome source DACs that are well known for excellent detail retrieval.
Mid-fi DAPs such as the X5iii and the Cayin i5 also sound excellent but from a different perspective. These two are inherently more musical sounding with the edge going to the i5 just for that slightly more dynamic feel to its sound putting a little more emphasis on top end reproduction which is where the MJ2 sounds at its finest. The X5iii though is an excellent pairing for vocals and low-end physicality and is only a hair’s breadth behind the i5 for top end articulation.
The HS-04 review just came out a few weeks ago and its purposed for a mobile stats presentation in combination with the Kingsound Audio M-03 portable stats amp but can be connected to a desktop pro bias stats amp if needed.
Using the M-03 and DX200 (neutral as possible) the HS-04 and MJ2 had some striking similarities and some noticeable differences. Both have a slightly relaxed but very detailed signature with excellent extension and fantastic articulation.
Where they differ is in staging and low-end reach with the HS-04 displaying better low-end presence beyond where the MJ2 rolls off a little resulting in a fuller sub-bass response that still stays coherent and articulate. Both have tight bass responses but the HS-04 has a touch more power. The MJ2 is a little warmer compared to the HS-04 but its warmth and elevation is more mid-bass than sub so it will offer a more satisfying impact but not as much rumble.
Since the HS-04 is also circumaural with the better depth. It also has a wider and deeper soundstage than the more forward and intimate MJ2. The MJ2 is more enticing for vocals for me over the HS-04 with a smoother leading note but if you want something more expansive then the HS-04 is the better choice.
This is a classic and been around for ages in terms of recognized electrostatic headphones. It comes with its own mini box amp which is just so-so in terms of performance but can run out of a pro bias stats amp with a converter cable for an additional fee for the cable. Build wise it’s creaky, cheap looking and can’t hold a candle to the robustness and finish of the MJ2 but its potential for a pleasing stats sound is widely respected.
The Koss, much like the Kingsound, does have some similarities in terms of speed, imaging, and resolution but unlike the Kingsound the ESP950 does not have the same sub bass presence or mid-bass that the MJ2 offers.
Instead, the ESP950 focus more on a natural and very open sounding mid range that is slightly forward and very lifelike. The MJ2 is that bit more neutral and intimate in its mids performance though with clear and well-controlled vocals. Being of an open design the ESP950 treble performance is also just that bit airier and more spacious sounding than the MJ2’s closed back design. I would tend to veer to the ESP950 for rock and vocal work more but anything that requires a slightly fuller bass presence I would take the MJ2.
Being portable, easy to use on efficient and weaker amps also places the MJ2 up against a few non-stats headphones also. One of the standout units at this price point is the Oppo PM-3. The PM3 is the most efficient on ear portable planar headphone on the market and like the MJ2 it is a closed headphone. It is not quite as easy to drive as the MJ2 and does benefit from some quality amping but a decent DAP will work just fine with the PM3.
Form & Fit
Physically both have similar form factors as on-ear headphones with the MJ2 having the more attractive wood design and folding capability whereas the PM3 has those quality pads and excellent seal and comfort factor. Both comes with small carry cases and single short cables designed to promote both headphones as a medium of choice for portable use.
Tonally both are relatively neutral and err more towards a balanced flatter tone than anything overly colored. The PM3 has a heavier thicker sound than the lighter but speedier MJ2 but offers more physicality in its low-end yet still stays pretty coherent. Mids on the PM3 are largely linear with its bass response with a more forward vocal positioning than the MJ2.
The MJ2 though offers lightning-fast detail, excellent transients and can turn on a dime making the PM3 somewhat slower sounding in comparison and with imaging that is way behind in terms of accuracy. Treble on the MJ2 is also more dynamic sounding with better extension and articulation than the laid back but natural sounding PM3 top end response.
Truth be told when I was first approached to review the MJ2 I was a bit hesitant. The design looked great, the concept is excellent ‘old school new school’ technology but the change of hands and various sub-brands popping up had me worrying if this was a hot tamale too far. Well, thankfully I was completely wrong. The MJ2 is exactly the kind of headphone I could and should recommend to those who want a taste of stats without investing in an entire system and wishing to retain a high degree of mobility.
It has a full sounding impactful mid bass, a neutral, detailed and quick paced midrange. It offers excellent imaging and dynamics as well as an extended and articulate treble without a harsh note in sight in either its vocal performance or percussive attacks. The only thing it is lacking is sub-bass extension and a bit of texture in the mid-bass slam and perhaps a more open spacious sound but for a closed on-ear, it is not that far off.
For the offered price of $499, this is a competitive concept and I look forward to seeing if Mitchell & Johnson can take the original concept with Verisonix and build something with bigger drivers and a more open sound just to see if modern electrets can compete with entry level stats headphones. Interesting times indeed.
- Frequency Response: 6 to 50,000Hz
- Sound Pressure level: 120dB
- Impedance: 32 ohms
- Acoustic System: Closed back
- Total harmonic Distortion: <=0.1%