I’m going to start this review describing an exemplary unboxing experience, which speaks to Audio-Technica’s all-encompassing attention to detail. All three models of the company’s R-Series open-back headphones are packaged in precisely-assembled cardboard boxes. The ATH-R30x and ATH-R50x models unveil themselves when you slide open a catch-tab, unfold the top, and remove the paper cushioning material. The bottom then hinges open, which allows you to easily lift out the cardboard cradle, slide out the bundled cables, and remove the headphones. Everything is recyclable cardboard or paper, even the twist-ties, except for a couple very small pieces of tape that you lift off and discard. Even the hang-tab for retail display is a folded cardboard insert that can be flattened for maximum efficiency when stacking and shipping many boxes together. The ATH-R70xa model unboxes in a slightly more luxurious manner, with sliding sections of tucked-under cardboard reminding me of origami.
Once you don any of these headphones and turn on a song, it becomes clear that all the effort that Audio-Technica put towards perfecting the packaging is also evident in the actual products. All three models – despite spanning a big difference in price – are engineered and manufactured with materials and components that look and feel premium, and – importantly – keep these headphones featherweight. Each model has a thin metal headband with cutouts to reduce weight and manage springiness. The R70xa and R30x utilize a fabric-lined floating harness that wraps over the top of your head, adjustable with super-magnets on the R70xa and hook-and-loop on the R30x, while the R50x has two puffy cushions instead. All three are the most comfortable circumaural headphones I’ve worn. When I reviewed the original ATH-R70x model ten years ago [Tape Op #108], I characterized its sound as “warm and inviting.” The improved R70xa has a similar emphasis in the lows and mid-lows due to a bump in the frequency response at 90 Hz, with a slight downward slope to 400 Hz, and then flattens out to 1 kHz before falling again until reaching 4 kHz. Where the R70x has some attenuation between 4 to 7 kHz, the R70xa has more energy. The takeaway here is that the newer model gives a better representation of the spectral regions typically occupied by F2 vocal formants (crucial for distinguishing vowels) and sibilance; therefore, I find that mixing vocals is slightly easier with the R70xa. Meanwhile, distortion levels are low on both the original and improved models, even at frequencies below 150 Hz where other open-back headphones struggle the most. On both models, I can clearly hear the fundamental at 22 Hz, and any distortion I do notice across the spectrum is primarily second-order harmonics. Phase response is also close to linear, and, correspondingly, transient response is very tight, so you hear detail with very little resonance or masking. Bottom line, I can mix on these headphones and I don’t need to double-check the mix (especially the lows) on closed-back headphones or a subwoofer. I would go so far as to say that if I had only $349 to spend on a monitoring solution that I could fully trust for mixing – speakers or headphones – the ATH-R70xa would be my top choice. They sound wonderful while still allowing you to focus on minute details across the whole spectrum, and they’re all-day comfortable – fit-wise and in their lack of ear fatigue. If your budget is smaller, the $160 ATH-R50x would be a great choice at less than half the price. You do lose some detail due to a bit more distortion below 40 Hz and above 2 kHz, with higher-order harmonics becoming more prominent. There’s a very slight “smile” to the frequency response due to a mild emphasis in the highs, but nowhere near the kind of midrange scoop you experience from “lifestyle” brands. Driver damping is still well controlled, but the R50x’s measured impulse response does exhibit a bit more overshoot than the R70xa’s. Regardless, the R50x still sounds tight, punchy, and accurate. It’s also the loudest, requiring the least amount of power to reach ear-splitting volumes. The ATH-R30x at $100 is also impressive, given its build-quality and sound. Of the three models, it’s the only one that I would not consider “warm,” although it’s still “inviting.” As expected, the lows from the smaller 40 mm drivers aren’t as clear due to slightly more distortion from 45 Hz down, but I can still discern the fundamental down to 25 Hz before the harmonics start to mask it – an amazing feat for an open-back design. The highs are lifted from 5.7 kHz upward, and I can hear distortion from 4 to 7 kHz that adds sibilance to vocals and cymbals. Despite this, I would still consider this model non-fatiguing, because phase response is very linear, so psychoacoustically, I’m not struggling to hear details. Kudos to Audio-Technica for making a whole line of open-back headphones that look, feel, and sound fantastic – and most importantly, are truly great choices for mixing.