Pioneer S-DJ80X The Pioneer S-DJ80X active reference speakers are designed for great audio feedback while practicing DJing skills. The speakers feature excellent sound quality, improved bass response and reliability, three types of inputs, and built-in equalization, useful for DJs who want to achieve the highest accuracy in sound reproduction. Each speaker is sold separately. AUDIO QUALITY For maximum audio performance, increased bass output and reduced unwanted resonance, each speaker utilizes a highly rigid medium density fibre-board (MDF) for the construction of its enclosure and bass reflex ducts. Additionally, to optimize sound quality and increase reliability, Pioneer uses woofers made with aramid fibre cones and soft dome tweeters infused in magnetic fluid. Groove Technology: To improve airflow through the port of the enclosure, Pioneer engineered the port hole with grooves to help direct the sound waves smoothly. The technique decreases standing waves from the mouth of the port, resulting in smooth bass and mid-bass output, with more impact.