The latest collaboration between audio smiths Astell & Kern and Jerry Harvey, the Billie Jean finally graces my review desk.  But at a sweet, low $349, how does this earphone sound?  Does it really change the way you hear music, as Astell & Kern claims?  Is the sound worth all that cheddar?  Could you modify the sound by filling your ears with cheese?  Audio46 investigates.

The A&K Billie Jean comes in a smallish box with a modicum of accessories.  There are no sitickers or lapel pins, or anything so extraneous, really.  You get the earphones, some eartips, and a soft, zippered carrying pouch.

Design wise, the Billie Jean sports solid craftsmanship.  The earpieces feel fairly light in hand and fit easily into my giant dumbo ears.  But if you’ve got little, tiny ears, this earphone might require some getting used to.

There are two really major design choices, sound-wise, that may have caused the Billy Jean to appear on your radar:  two custom balanced armature drivers from Jerry Harvey in each earpiece, and the Acoustic Chamber bore design.  According to Astell & Kern, these features boost the sound of the earphone to incomparable heights.

Once situated in the ear, the design seems to hug the contours of the ear really well, leading to natural fit that you can easily forget about as you’re swept away by the sound.

Supplied with a braided removable cable, the BJ sports a 2-pin connection.  The cable looks like any other standard 4 ft headphone cable, but actually rocks some silver-plated copper.

Specifications

Frequency Range:  NA
Nominal Impedance:  18 ohms
Sound Pressure Level (SPL):  NA

As we can see from these specs, Astell & Kern plays it pretty close to the chest when it comes to the BJ.  Yet, if I had to guess at a frequency range, I’d posit that it lands somewhere around 5-19,000 Hz or 5-20,000 Hz.  Nominal impedance measures at just 18 ohms – highly efficient and perfect for low-output devices like smartphones and computers.  Sound pressure level, also not rated by the manufacturer, seems decent – right around or just shy of 100 decibels, so achieving adequate volume shouldn’t be an issue.

Low End

The Billie Jean holds a powerful, driving low end. Detail might seem a bit compressed, but this part of the frequency range still appears full to the point of bursting. A strong emotive bass lies at the heart of the BJ, providing jaw-dropping impact but never sounding too sloppy or uncontrolled.

This is the perfect low end for Bass Heads.  

Midrange

The midrange houses good detail, even if that detail sounds slightly distorted. Somewhat overshadowed by the low end, these mids don’t sound horrible – they just don’t seem like they are receiving as much attention as the lows. Yet, the subdued sound somehow jives with those lows, creating a deep, dark character wholly unique to the Billie Jean.

High End

Bright, but only just so, the highs on the BJ strut a fine, thin line. They might miss some nuances, but still deliver relatively decent resolution, while smoothing the edges on most of the high highs. Add this to the low end and you’ve got one helluva dynamic sound.

Soundstage

Fantastic depth with acceptable placement give you a fairly impressive sense of soundstage. Can it compare to an open-back design? No, but for an in-ear design, this headroom will still razz your berries.

Other Observations

Lightweight and comfortable, the Billie Jean does what any good earphone should: get in my ear and then get out of the way. Soon I forget that I’m even wearing these things, and lose myself in that wild, primal bass.

And speaking of that bass, it’s growing on me. Slowly but surely, I am reveling more and more in the sound. A deep, sludgy, kludgy, buttery bass that crawls and creeps. This is not the kind of prim and proper bass you want to take home to your mother.  This is the kind of twisted, freaky bass you want to pass out with while Alice In Chains or Ozzy blasts your ears.

Recommendations

For those seeking proper detail in a bassy package, the BJ will fail to disappoint. However, if you’re looking for a more even, balanced sound, I would recommend the Shure SE435 at $399. Anyone who prefers more mids and highs but abhors bass should check out the Westine UM Pro 30 at $399.

Final Analysis

Rocking a whopping strong bass and solid detail, the Astell & Kern Billie Jean is a no-nonsense pair of ‘phones that hits you hard. At $349 the low-end-heavy sound commands an interesting place in the current market, with no true competition. If you want to hear bass, you could probably opt for a cheaper pair of headphones. But to actually FEEL bass, skip the BS and snag this gem.