Koss PortaPro Review

Introduced in 1984 the PortaPro has remained Koss's greatest and most popular headphone. Featuring unparalleled performance within its price segment, the PortaPro is a sure bet for anyone interested in an open mid-fi headphone. Did we mention it has a no-questions asked lifetime warranty? Frequency Response: 15-25,000 Hz Impedance: 60 ohms Sensitivity 101 dB SPL/1mW Distortion: Cord: Straight, Dual Entry... more