The DT990 Pro X provides a great headphone experience for the price. It is accurate, comfortable and honest. I needed a replacement for my previous open-back headphones (Teufel Aureol Real, 2012), because it developed noticeable distortion recently.
Sound: The DT 990 Pro X seems to be very suitable for listening and mixing, as I was able to clearly pinpoint buried details in recordings (i.e., Kansas, Blue Öyster Cult, Led Zeppelin, etc.): I was pleasantly surprised! The clarity and honesty are impressive.
Ergonomics: The DT990 Pro X is comfortable. The weight and pressure distribution around the headband and ear pads are well balanced and did not cause neck fatigue even after hours of wearing them. The cushions seem to be easy to clean, but time will tell.
Build quality: The cable is well made, noiseless when moving around and the screw-in adapter is nice. I bought a coiled cable in addition to the straight one, because I have a setup that requires switching sources. The plug and socked seem to be solid enough, but again: time will tell how well those hold up.
The metal frame of the DT990 Pro X makes a sturdy impression, the edges are not sharp, but I would have liked the edge radius to be a bit larger for comfort and avoiding scraping/scratching on softer surfaces.
The included carry bag is quite thin: It will not protect your phones from any impacts, but that is also not the purpose of it...
Overall: I am very satisfied with the DT990 Pro X. It sounds great, wears comfortably and makes a sturdy impression. When putting it on for the first time I was impressed with the pleasantly detailed sound stage, without being overwhelming.
Footnotes: Compared it to my Shure SE535, Teufel Aureol Real (which it replaced) and Apple Ear Pods Pro 2. The DT990 Pro X sounded better to me, except that the Shure has more detail separation, esp. in the lowest and highest frequencies (at 2.5X the price). Compared analog, lossless digital and compressed digital recordings.
