Review: Pioneer SE-MJ591 Headphone

Pioneer’s gotta be a little PO’ed. The storied Japanese company has been making headphones for more than 50 years, yet it’s been overshadowed by upstart brands like Beats, HiFiMan, V-Moda, Phiaton, and others. But Pioneer’s fighting back with a freshly designed new line, in which the SE-MJ591 on-ear headphone is one of the top models.

The SE-MJ591 is a little unusual. The included case and fold-up design suggest it’s designed for business travel. Sleek chrome-on-black styling and a $300 price tag slant it more toward 30- or 40-something biztravelers than 20-something aspirers. Yet it lacks the one feature most desired by the frequent flyer set: noise cancelation. What’s going on here?

To get a broader perspective on the SE-MJ591, I brought in two of our frequent headphone testers, L.A. voice actress Lauren Dragan and jazz musician Will Huff. Lauren compared used her recently acquired PSB M4U 2 headphones as a reference, while Will and I used various other headphones we had on hand. I later compared the SE-MJ591 to a well-regarded competitor, the $230 V-Moda Crossfade M-80. Lauren used an iPhone as her source, and I used my iPod touch and my Motorola Droid Pro. Will and I also listened with my Denon DVD-2900 DVD/SACD player feeding a Rane HC6S professional headphone amp. The SE-MJ591 performed similarly no matter what sources we used, so it will work fine with just about anything you want to hook it into.

Pioneer definitely got the look and construction right. The softly padded earcups swivel to assure a good fit. The panelists didn’t complain (as they often do with on-ears) at all about the comfort. I wore the SE-MJ591 on a flight from L.A. to Houston, and found it to be one of the more comfortable on-ears I’ve worn. I needed a 2-minute break after about 60 to 80 minutes of wearing it, but the fact that I could keep it on through two average-length albums says a lot.

OTOH, I really missed having noise cancellation. The roar of the 757’s engines rumbled right through the SE-MJ591’s earpieces, requiring me to turn the music up a lot louder than I’d have preferred.

Plane Sound

On the plane, listening mostly to jazz stuff like the Pat Martino Quartet’s burning new release Undeniable, the SE-MJ591 sounded pretty good. It seemed to have an upper midrange emphasis that brought out more detail in Martino’s guitar — a good thing, ’cause Martino’s recorded sound is often too dull for my taste. “Sister Andrea,” from the Mahavishnu Orchestra’s The Lost Trident Sessions, sounded even better, the SE-MJ591 nicely articulating the dueling wails of guitarist John McLaughlin and violinist Jerry Goodman, as well as Rick Laird’s tight bass line.

Switching to more demanding pop and rock recordings, and listening in a less-noisy environment, spotlighted the SE-MJ591’s unusual tonal balance. “There’s not much bass, and what bass there is really falls off at the lower frequencies,” Lauren complained. “The higher frequencies dominate, so the sound is really in-your-face and the attack is overpowering.” Will also complained about an emphasis in the mids and highs.

I found vocal reproduction especially problematic for the SE-MJ591. Vocalists ranging from Bebel Gilberto to Ron Sexsmith to Donald Fagen exhibited a filtered effect, almost as it they were singing through toilet-paper tubes. (Will described the effect almost exactly the same way.) The acoustic guitars on the Chesky CD The Coryells had a plasticky, toylike sound. I got little sense of ambience and “air” no matter what I played. The bass had an overly punchy, high-Q sound, as if one narrow resonant band was dominating and the rest was largely missing.

A lot of headphones tuned for hip-hop and rock sound bad with pop music, so I switched to Mötley Crüe’s “Girls Girls Girls.” No better — the sound still seemed strangely filtered, as if it’d been run through an EQ with extreme settings.

Compared to the V-Moda Crossfade M-80, a well-regarded on-ear model that lists for $70 less, the SE-MJ591 sounded unnatural and relatively thin. Voices sounded much more natural through the M-80, and its treble sounded smoother, lusher, and less harsh. The M-80’s bass is a bit much for me, but I’d rather have a bit too much bass than too little, and my guess is that most people would agree.


To measure the SE-MJ591, I used a G.R.A.S.43AG ear/cheek simulator, a Clio FW audio analyzer, and a Musical Fidelity V-Can headphone amplifier. I experimented with slight differences in position of the earpieces to get the best seal of the headphone on the cheek plate and the most representative frequency response curves. As with many on-ear models, I had to use the 43AG’s clamp mechanism to get an adequate seal of the earpieces on the simulator’s phony rubber ears.

The frequency response measurements of the SE-MJ591 are unusual. Although the difficulty of getting a good seal on the simulator with on-ear headphones makes any bass response measurement ballpark at best, this does seem to be an unusually bass-shy on-ear headphone. Most headphones have a response peak around 2 to 3 kHz, but on the SE-MJ591, it’s much lower: 1.5 kHz. The treble response appears somewhat attenuated, although it didn’t sound that way, probably because the lack of bass counterbalanced the measured lack of highs. Adding 70 ohms output impedance to the V-Can’s 5-ohm output impedance to simulate the effects of using a low-quality headphone amp has no significant effect on frequency response.

Total harmonic distortion (THD) at 100 dBA is exceptionally low, under 1% at all frequencies (even at 10 Hz—wow). Impedance is essentially flat, running between 30 and 33 ohms. Isolation is pretty good for a passive on-ear headphone: about -10 dB at 1 kHz, then dropping to -15 to -25 dB between 1.5 kHz and 15 kHz.

I measured sensitivity with a 1 mW signal at the rated 32 ohms at 105.7 dB from 300 Hz to 10 kHz, and 107.7 dB from 300 Hz to 6 kHz.

Bottom Line

Opinions about headphone sound are personal, and we can’t say you won’t like the SE-MJ591, but none of us enjoyed its sound. It’s a nice design, we just wish it had a more neutral, natural sound.