By no means new, the PSB M4U 2 claims to deliver hifi sound, noise cancelling, and built in amplifiers – all at a price point of $399. Â Keeping that in mind, how has it handled the test of time? Â Is it still the reigning champ when it comes to high-end noise-cancelling, or has it been usurped by upstarts?
PSB M4U 2 Review
There’s  some impressive packaging involved with the M4U 2.  Inside the thick cardboard box, you’ll find two headphone cables (one with a mic and remote), an airplane adapter plug, a 1/4” stereo plug, and two AAA batteries.  There’s also a thick case, holding the headphones and an extra pair of pleather earpads.
Seeing the headphones for the first time, I couldn’t help but think “they’re asking $399 for this?”  The headphones feel cheap and plasticky, and they remind me of really junky bluetooth headphones from China.  So…these may not engender a lot of confidence at first glance.  They’re also kind of bulky-looking.
Once you put them on your head, though, you have to give PSB credit for at least making them pretty comfortable. Â Most headphones this size tend to make me feel like one of those bobblehead dolls, but these remain pretty light (thanks, plastic!).
Specs
Frequency Response: 20-20000 Hz
Sensitivity 102 dB @ 1kHz/1mW
THD (ANC off): 0.25%
THD (ANC on): 0.5%
Maximum Power Handling: 30 mW
Impedance: 32 ohms
Transducer Type: Dynamic
Operating Principle: Closed
Size: 40 mm
Ear Coupling: Circumaural
Connection: 3.5 mm
Construction: Polycarbonate
Weight: 362 g (12.8 oz)
Battery Life: 55 hrs
Cables: (1) 6 ft (1.5 m) push-function remote cable and (1) 6 ft (1.5 m) monitor cable
As these specs show, we’ve got a headphone on hand that offers a standard frequency range, a low impedance, and some surprising low distortion. Â Volume levels should be decent, and the battery life is very competitive.
Low End
The low end on the PSB M4U 2 is relatively deep-sounding, though with slightly less detail that some other high-end options at this price point. Â With the amplifiers turned off, the bass still has some impact, with good control that leads to only the slightest bit of bleeding. Â With the amplifiers turned on, however, the bass gets downright booming, but the control gets worse, and it bleeds like crazy.
Mids
These headphones have an astounding midrange that we just were not expecting. Â There might be a shade of compression in there, but it’s barely noticeable to me, and I think casual listeners may never notice it. Â Overall, the mids have some impressive accuracy that do much to elevate this headphone above its cheap build.
High End
The high end seems to follow the examples set by the low end and the mids: Â despite some minor flaws, the sound remains one of quality. Â Despite some rolled-off quality in the extremely high notes, the sound is pretty smooth and pleasant, with some knockout female vocals. Â When the amplifiers are turned on, there’s some interaction with the high end – possibly more articulation – but whether this is good or not, I can’t tell.
Soundstage
Soundstage is pretty much what we have come to expect from closed-back headphones. Â There is the slightest impression of space and depth to the music, but even this is still too compressed for our tastes.
Noise Cancellation
The Active Noise Cancellation feature seems to work okay on these headphones. Â While not as impressive as the technology on certain Bose or Audio Technica models, it does offer the option for those who really need it. Â And while there is some ample detail in there too (something that knocks the socks off of Bose or Audio Technica), I was more than a little miffed that the amplifiers remain on with the ANC – resulting in what I thought was a less-than-stellar sound with too much bleeding in the low end.
Overall Impressions
The PSB M4U 2 is a relatively high-end headphone that happens to have active noise cancellation and built-in amplification.  For $399, it performs quite well, even if you don’t  plan to use the extra features PSB has brought to these headphones.  As far as standing the test of time, these headphones have managed.  Of course, newer models from other brands may best them in one area of another, but it’s hard to write these cans off completely because they just sound so. damn. good.
Recommendations
Where active noise cancellation is concerned, these headphones don’t necessarily edge out Bose QC25. Â But…if you’re after a headphone that delivers great audio, and you also might want some noise cancelling technology thrown into the mix, these are the headphones for you. Â If you’re after a full, luscious bass and noise cancellation, and you don’t know what bleeding is, these are the headphones for you, too.
Compare the ranking of various headphones, earbuds and in-ear monitors using our tools.
Discuss this, and much more, over on our forum.
---MAJORHIFI may receive commissions from retail offers.