The original pads that came along with the headphone were more than 3 years old and completely devoid of any pleather covering. As such the sound had degraded to such an extent that I could hardly hear any bass. The headphone sounded "dead". After a lot of hesistation, i went in for the Hybrid pads. Immediately, i could hear a big difference. The bass on my M50x is back!! As the driver is a bit more distant from my ear as compared to earlier, i can hear a slight increase in dimentionality in the upper frequency, in other words, it sounds more spacious. Really happy that my headphone is back as new (or better than new). Thank you Brainwavz!