The Japanese company Audio-Technica is one of the top producers of professional audio equipment since 1962. I am going to compare Audio-Technica ATH-M70x vs Audio-Technica ATH-M50x, closed over ear wired headphones, to define what makes them different and help you to choose your best.
The headphones are similar with their close impedance of 35 vs 38 Ohm and sensitivity of 97 vs 99 dB. But in frequency response M70x is stronger with its 5Hz-40KHz vs 15Hz-28KHz of M50x.
Audio-Technica ATH-M70x sound very neutral and flat, that is great for mixing and recording when you do not want anything to be overwhelmed, but not for enjoyment. I find the highs not very bright and bass too flat.
The sound of ATH-M50x is very crisp, harmonious, and live. It feels like the way it’s been recorded that is great for mixing and critical listening. That is pleasant also for casual listening. The bass is quite enough, tight and strong. The trebles and mids are bright with distinct vocals and instruments. They seem to lack soundstage for the closed cups design, however that works a bit to isolate the sound.
The M70x is slightly lighter than M50x with 280 vs 285 g. M50x are foldable, but come with a carrying pouch unlike unfoldable M70x but with a hard case to keep it safe and sound. The headband of both is soft padded and adjustable for comfort, thus M70x feels lighter and softer on the head and seems better for long sessions. Both are comfy and safe with their detachable cables and extra audio cable in a set.