- USB audio decoding and output for PC, functioning as a high quality external USB soundcard*;
  - Texas Instruments’ PCM2706 serves as USB receiver. For better sound quality, a Wolfson WM8740 serves as digital-to-analog convertor (DAC), pairing with a high performance operational amplifier from ADI for the DAC circuit;
  - Build-in headphone amplifier utilizing AD8692 and Texas Instruments’ TPA6130A as pre- and power-amp for high performance, good resolution, low distortion, and powerful output;
  - Standard 3.5mm stereo line-in jack for portable amplification with conventional audio source;
  - Dual 3.5mm headphone output jack. Convenient design makes it easy to share music between two listeners;
  - World’s first portable headphone amplifier with dual colors OLED display;
  - Easy to use digital volume control function with great precision and channel balance;
  - Build-in EQ for 3 levels of Bass Boost;
  - Build-in rechargeable 1050 mAH Li-ion battery for 80 hours of continuous operation**;
  - Specialized dock for connecting E9*** to experience an even higher performance;
  - Quality anodized aluminum satin finish case design, small and compact, ideal to be wrapped together with digital audio player;
  - User selectable USB charging function to help prolong battery lifespan and lower distortion from power supply circuit;
  - User definable startup volume memory and maximum volume limiter to protect user from hearing damage due to loud volume;
  - Automatic keylock feature;
  - User definable sleep timer function and total runtime display****.

* This model supports driverless plug and play on Windows XP, Windows 2000, Vista, Windows 7, and various Mac OS.

** Full battery charge via computer USB port after 200 minutes and capable of 80 hours of continuous operation, tested under laboratory condition for evaluative purpose only.

*** E9 is a desktop amplifier with greater output, better performance and an integrated E7 specified dock connector. With the dock, E7 can easily establish a line-out connection with E9 and transform both together into a high performance desktop amp with USB decoding function, capable of PC connection and recharging functions, etc.

**** Total system runtime will accumulate from the first use. It will be reset to zero after either reset button is pressed, reloading default setting, or when the battery depleted

Specification
  - Output Power: 150mW (16Ω)16mW (300Ω)
  - Headphone Impedance Range:16 Ω ~ 300 Ω
  - SNR:≥95dB (A weight)on line-in  ≥100dB (A weight)on USB-in
  - Distortion:  <0.009% (10mW)on line-in; <0.008% (10mW) on USB-in
  - Frequency Range: 10Hz ~ 1000KHz
  - Power Supply: Rechargeable Li-ion battery
  - Recharging: USB 5V DC 400mA
  - Size:96mmx55mmx15.5mm
  - Weight: 100g