Key features

• •Package Includes: (1) KRK KNS-6400 Professional Dynamic Studio Monitor Headphones KNS6400, (1) Rockville HeadRock Battery Powered Rechargeable Personal Headphone Amplifier Amp.
• •Features of KNS-6400: Voiced to remain true to the character of KRK's class leading studio monitors, developed with 25 years of years of experience in studio sound, The latest reference quality frequency response for closed-back, circum-aural dynamic headphones, Newly developed headphone acoustical system bringing a new level of headphone performance for the first time, Utilizing the latest in acoustic memory foam technology ensures class leading performance in both reproduction and isolation.
• •A new standard in headphone comfort, even over extended periods of use, designed to avoid feeling uncomfortable during long sessions. The special foam conforms to the ear to help ensure an improved fit, Exceedingly accurate, natural and wide frequency response, Large dynamic range with extremely consistent low-distortion detail and clarity, Extended low frequency definition, ensures the bass component of your music is accurately reproduced, and is not lost.
• •Features of HeadRock: Rockville HeadRock Battery Powered Rechargeable Personal Headphone Amplifier, 3.5MM headphone output, 3.5MM aux input for music player, Lithium Battery with 800mAh capacity, Rechargable battery lasts 5-8 hours per charge, Headphone Amplifier Works with 16 - 300 Ohm Impedance, Headphone output power: 65mW@16O 89mW@32O 95mW@64O 69mW@120O 29mW@300O, High/Low gain switch.
• •Volume control, 300mv - 2000mv, Strong aluminum case ensures long life and strong heat dissipation, Chipset: NE5532, THD: 0.0001%, Signal to Noise Ratio: 125dB, Frequency Response: ±odB (20Hz-20kHz), AMP Internal Voltage: 8V / 500mA, DC power Charging: 5V 1A, Weight: 0.17 lbs, Dimension (inches): 3.74" x 2.09" x 0.5" ( L X W X H).