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I’m always excited to try high-end in-ear monitors. Bluetooth earbuds have their place and use, but there’s something to be said for multi-driver earphones that aren’t as restricted by batteries, antennas, and rigid, low-end price points. Well, there’s a lot to be said, actually. In this case an entire review’s worth about 64 Audio’s Aspire 4 earphones ($899, all prices USD).
They’re quite unassuming at first glance, with a modest black-on-black design and just the company’s logo adding a small splash of silver. Inside, however, there’s a lot going on. Many recent earbuds have downsized to a single dynamic driver. Sometimes you can find models with two. As the name suggests, the Aspire 4s have four drivers inside each earphone. That’s all the more impressive when you consider that the buds themselves are relatively small. For low frequencies there’s a single dynamic driver; midrange is handled by two balanced-armature drivers, and an additional balanced-armature reproduces the treble.
So I was certainly curious to hear whether 64 Audio would be able to get all the drivers playing nice with each other, especially in a tiny enclosure.
In the box
As you’d hope for $900 earphones, there’s lots in the box, starting with a small case with a logo that matches the black aesthetic of the earbuds. An impressive 12 different eartip options are included: four materials with three sizes each, including Comply foam and silicone. I’d have preferred four sizes with three materials, or some variation on the standard small, medium, large. But most people should be able to get a secure and comfortable fit.
The braided, removable cable is silent when rubbing against fabric, something a surprising number of companies overlook. A small cleaning brush, shirt clip, and 3.5mm-to-6.35mm (¼″) adapter round out the accessories.
Use
The 48″ cable is long enough to reach a device in your pocket, but feels a bit limiting if you have an amp on or near your desk. Not a big deal, but worth noting. As is fairly common with in-ear monitors, you wrap the cable up and over your ears. So installed, they’re quite comfortable.
Sound
To put it simply, the Aspire 4s sound great. Detailed but mellow treble, a surprisingly wide soundstage, and warm bass. They excel at a wide variety of music, from EDM to jazz and classical.
Acoustic instruments, like guitars and pianos, had an inviting realism. For instance, Dave Brubeck’s piano on stage at Carnegie Hall playing “Take Five” (The Dave Brubeck Quartet at Carnegie Hall, 16-bit/44.1kHz FLAC, Columbia Records / Qobuz) had a rich tone, and seemed to appear well over my right shoulder. Paul Desmond’s alto had all its airy yet dark, glorious sound. Joe Morello’s cymbals, sounding well out over my left shoulder, were higher in the mix than I’ve heard, but not overly so. They sounded crisp without being biting or harsh.
Leaping genres enough to give some people whiplash, Charli XCX’s single “Guess featuring Billie Eilish” (24/44.1 FLAC, Atlantic Records / Qobuz) is a driving dance track with a lot of bass. The Aspire 4s handled this track easily. There was extra bass for sure, but it was very well controlled: punch, not boom. Despite the plethora of low end on this track, the vocals weren’t lost. When Eilish’s breathy voice arrived, it took center stage and didn’t get overwhelmed. The growly synth toward the end of this track, practically a square wave in its tone, was aggressive, but not annoyingly so.
Somewhere between those is the moody “Nightswimming,” from R.E.M.’s classic Automatic for the People (24/192 FLAC, Warner Records / Qobuz). The piano competed a bit with Michael Stipe’s voice, but only slightly. There wasn’t quite as much air and space in this track as I’ve heard with other earphones, but overall, it was well balanced—a warm, lovely listen, if a little mellow.
Perhaps most surprising, given the myriad drivers, was that the Aspire 4s weren’t difficult to drive. I was able to get an uncomfortably high volume level even out of the wheezing amp in the Sony NW-A306.
Comparison
I didn’t have a pair of IEMs that exactly matched the price of the Aspire 4s on hand, but I did have the Meze Audio Advar ($699) and the Meze Audio Rai Penta ($1099) earphones. These offer potential bookends to the Aspire 4 earphones’ performance.
Starting with the Rai Pentas and Jeff Buckley’s “Hallelujah” (Grace, 24/192 FLAC, Columbia Records / Qobuz), the Mezes had a bit more snap in the upper midrange, with a little more sibilance. Both are fairly mellow earphones overall, with a fair amount of bass. I think I lightly prefer the Aspire 4s, but if someone said they preferred the Rai Pentas, I wouldn’t be able to argue. Either way, they’re far closer in sound than their prices would imply. I’d call that a win for 64 Audio.
The Advars have only a single 10.2mm dynamic driver in each earbud. With Led Zeppelin’s “Over the Hills and Far Away” (Houses of the Holy, 24/96 FLAC, Atlantic Records / Qobuz), the opening guitar sounded a bit smoother and more realistic via the Aspire 4s. The Advar earphones’ midrange was smoother and more balanced, however, and there was a bit more upper treble, so Bonham’s cymbals had slightly more air. The Aspire 4s had more bass, though not so much that it was unbalanced with the mids and treble.
Conclusion
My only complaint about the Aspire 4 earphones—and it’s a minor one—is their aesthetics. Let’s call their look “subdued.” Other 64 Audio models have more flair, though they’re all a lot more expensive. The Aspire 4s might be the least expensive in their universal-fit line, but $900 isn’t cheap by any stretch, and I don’t think it’s unreasonable to expect a bit more in the looks department. Again, a minor complaint. There’s certainly a case to be made that “unassuming” is exactly what you’d want when walking around with $900 earphones.
Beyond that, I really liked the Aspire 4s. They’re not quite as open-sounding as I’ve heard, though I wouldn’t call them dark, and perhaps a little more low bass would be nice, though they have plenty of bass in general for my tastes. Overall, their sound is smooth and powerful and an enjoyable and fun listen.
. . . Geoffrey Morrison
Associated Equipment
- Portable media player: Sony NW-A306
- PC: iBuyPower Windows 10
- DAC/headphone amplifier: Schiit Audio Magni
64 Audio Aspire 4 earphones
Price: $899
Warranty: Two years
64 Audio
4510 NE 68th Drive, Suite 102
Vancouver, WA 98661
Phone: 1-833-642-8346
Website: www.64audio.com
