HD 555

The Sennheiser HD 555 headphones are full-sized, open-back, circumaural headphones designed for comfortable extended listening. With a classic design, they feature a robust build including a one-sided cable input and a stable headband with a high-quality mechanism for size adjustment. The earpieces are unique in their design, featuring angled drivers and a 'surround reflector' to enhance spatial sound reproduction, part of Sennheiser's 'Eargonomic Acoustic Refinement' system. The plush velvety ear cushions contribute to the overall comfort, making them suitable for long listening sessions, though some users may find them slightly firm. Weighing approximately 260 grams (9.2 oz) without the cable, they are relatively lightweight. The cable length is generous at around ten feet, terminating in a quarter-inch plug suited for full-size audio equipment, though an adapter for smaller devices is included. The headphones have a nominal impedance of 50 ohms, allowing for greater compatibility with a wider range of audio devices, enhancing their versatility for both home and portable use. The frequency response of the HD 555s is well-balanced, providing clear treble, satisfactory mids without distortion, and sufficient bass response, making them suitable for various music genres. While they aren't the absolute best headphones available, they deliver impressive sound quality at a mid-range price point, making them a compelling choice for casual listeners and audio enthusiasts alike.