• Jude, Head-Fi: "I really like it, and it’s a big improvement over the prototype.”

• John Grandberg/project86, Head-Fi: "I liked the prototype but I love the final production model. This is among the smoothest response I’ve heard from any of the HD6 series. Upper mids and highs are just so well controlled and clean, without losing much detail or feeling overly dark. There’s still an awful lot of air up there beyond 8kHz. Bottom line, for me, the $150 HD58X is arguably one of the best entries in Sennheiser’s HD6-series, and the absurd price advantage it carries over all other models makes it an easy recommendation."

• Solderdude, DIY Audio Heaven: "The HD58X has the best bass extension of Sennheiser’s HD6** series headphones. At this price-point the HD58X is very hard to beat."

• Marv, Super Best Audio Friends: "This [production revision] corrects minor issues with the original pre-production HD58X such as the lack of bass extension and a small peak at 5.5kHz. The issues were minor, and given Massdrop’s price, easily forgiveable. Now that these issues have been corrected, what we have now is a headphone with an amazing performance-to-price ratio. The lows now extend as well as the HD6XX headphones, and actually sound clearer. There is actually more clarity in the bass than the HD6XX! Not quite as good as the HD600, but somewhere in between, closer to HD600."

• Ken Denmead, GeekDad: "At their introductory price of $150, they’ve just set a new standard for entry-level audiophile headphones, and considering that you don’t need an amp to drive them, Massdrop and Sennheiser have just brought great-sounding audio down to a level where a lot more people can afford to hear what they’ve been missing."