Austrian Audio's new foldable headphones Hi-X15 and Hi-X25BT are something for your ears! While the Hi-X15 operates exclusively analog, the Hi-X25BT also offers a Bluetooth interface. The imaging frequency spectrum of both models ranges from 12 Hz to 24 kHz and their sound pressure level is 113 dB. The impedance of the stable headphones designed for studio, rehearsal room and stage is 25 ohms each. Under the hood act 44 mm Hi-X drivers which should provide a precise and clear sound reproduction. In addition to the high wearing comfort, the ear pads should also be interchangeable.