Legitimate record pools like Mashup Record Pool operate under royalty‑paying licenses (e.g., through the AllTrack system or direct label agreements), allowing DJs to legally play mashups in commercial settings. However, some “mashup pools” exist in a grey area — always verify that a pool has proper licensing before using it professionally.
DMS is expensive ($50+/month), but it is the gold standard for celebrity DJs. Their mashups are often studio-grade, using acapellas ripped directly from master tapes. Club residents and touring DJs who cannot afford a single bad edit.