FiiO E7 USB DAC Headphone Amplifier
Audiophiles often discard the earphones that come with most MP3 players in favor of those manufactured and marketed by third-party companies. This is because the latter have better audio quality, are more comfortable to wear, or have better sound-isolating capabilities. Literally between the MP3 player and the earphones, another device can be inserted to further improve sound quality –a headphone amplifier, such as the FiiO E7 USB DAC Headphone Amplifier.
The E7 measures 96 x 55 x 15 mm and weighs 100 g. It might be a little big but with its weight, it is still portable. At the bottom are a mini-USB port allowing it to be used as a USB sound adapter and for charging its battery, an analog 3.5 mm line-in port for connection with an MP3 player while you are on the go, and a proprietary dock connector that will link it with a desktop amp FiiO is currently working on. Two 3.5 mm output ports are found at the top of the E7. These allow you to share your music or movie audio with someone as long as you have similar ear or headphones.
On one side are four control buttons that perform multiple functions. These control volume, choose firmware menus, act as control and escape buttons, and turn the unit off or on.
The E7 features a bass booster in three levels, increasing bass by 2.5 dB at the first level, 3.5 dB at the second, and 4.5 dB at the third. Hissing, which is common in other portable amps with low impedance and sensitive phones, is greatly minimized. It has good channel separation capabilities with low distortion, and low noise floor.