The A 1 lets your high-end headphones unleash their full performance reserves & gives them independence from the sound & volume influences of other devices in the audio system. The A 1 is specially harmonised to the needs of audiophile-quality headphones from 32 to 600 Ohms & stands out for top precision & famous ‘made in Germany’ craftsmanship. The generously dimensioned power adaptor with a toroidal core transformer ensures powerful deep bass reproduction no matter what the situation. The ultra-linear frequency response of up to 100 k Hz makes the A 1 especially suitable for the reproduction of high-definition media like SACD & other HD audio sources. On the inside, the A 1 is h&-built from discrete electronic components. The front panel & volume control are produced from solid aluminium, with an ALPS precision potentiometer used to control volume. The A 1 has two separate inputs, with silent push buttons for switching between them. Input 1 features additional output jacks for problem-free integration of the A 1 into existing signal channels. Press commentaries: " The special circuit design features an amazingly natural sound reproduction with an excellent resolution & spatiality. The entire circuitry is capable to transmit 96 k Hz allowing the transmission of the whole frequency response of a SA-CD..." " The combination of selected high-grade components allows even the highest-impedance headphones to be driven flawlessly over the entire frequency range." (gpsobserve.info, 09/2010) "... the A1 seems to have as much or more output capability than any amp we’ve had around.. ." "... the A1 has a sense of dynamic ease that is consistent with the observation that it drives all sorts of headphones easily." " If high output impedance works for your headphones, & you yearn for a lively but not edgy sound, I think you’d really enjoy the A1." (AVguide.com, Playback 32, 06/2010) " Against its rivals, who often seek a mellifluous, valve-like sound, the Beyerdynamic A1 has studio-like neutrality as its design concept." " It’s not just the sound the A1 makes that impresses; it’s also the silence. Given a suitable recording, this headphone amp recreates inky depths of silence that’s the preserve of the very best amplification." " Whatever the price of headphone, the A1 seems to extract the very best from it in terms of separation & ultimate width of sound." (sennheisernoisecancellingheadphones.net, 06/2010) • Ultralinear frequency response • Maximum power for headphones with 32 to 600 Ohms • Volume control with ALPS potentiometer • Two stereo inputs, one stereo output (Chinch) • Headphone connector 6.35 mm with gold plated contacts