The HD631 series is a high sound quality headphone developed specifically for professional DJs and other critical monitoring applications. It is designed to clearly emphasize the beat of the music as well as capturing its more subtle nuances. Featuring 51 mm (2") extra-large diaphragms and high-energy Neodymium magnets, the HD631 series presents an excellent, balanced sound profile while giving an extra punch to the low end frequencies. Even the most critical professional DJ or audio professional will find the HD631 series ideal for delivering the exact sound performance they need to do the job. The HD631 features an exceptionally rich low-mid response, ideal for delivering a powerful musical beat delivering exceptional clarity and musical detail. With its high ambient noise isolation ear pad design, the HD631 series headphones easily help you to cue up the next song even in a noisy environment. The swivel mechanism of the ear cups can turn 180 degrees for more convenient single-ear monitoring styles. Comfortable caliper pressure and an ingenious auto-adjustable headband construction ensure a perfect fit, maintaining comfort even in long sessions. The HD631 series is a truly great value and should be your first choice in a DJ headphone offering the best performance quality, fit and durability for professional applications.