The HD 25 Headphone from Sennheiser provides high-quality audio in a lightweight and improved design. It can be used in several applications for monitoring, recording, DJing, and more. Featuring the same technical specifications and – most importantly – the sound as the original HD 25, the mechanical joint between the actual ear-cups and the headband has been improved and its joints are now more solid, providing a smoother adjustment for a better fit. The silver A1 from FiiO is a portable headphone amplifier with volume control, hi-fidelity output, and four EQ modes providing maximum flexibility. It can be used for smartphones, computers, tablets, iPods, and MP3 players to increase volume and deliver a more satisfying experience when listening to audio.