What sounds "better" can be a quite subjective process, and is more-so determined by personal preference.
What I can tell you is that the PRO500MK2 spec better than the AX1iS. However, the AX1iS feature a universal mic, volume & track control for Smartphones and other listening devices including Android phones, iPhone, iPad and iPod. The PRO500MK2 are DJ Headphones, which feature a tighter fit, are "louder", and extended frequency/bass response.
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