The Simpl Acoustics A1 headphone amplifier is slightly smaller than the standard size iPod. It comes with its own internal Lithium-ion rechargeable battery, USB charging cable, and a mini plug connecting cable.
The amplifier will work with any music device that has a mini plug headphone jack, but is sized to slip onto the back of the full size iPod players using rubber "podGrips".
There are two mini plug jacks on the top of the A1. The right jack is for the headphones, the left is for connecting the headphone jack of the iPod.
The center white button is the power switch for the amplifier. The device is switched on when the green LED is lit.
The internal Lithium-ion battery is recharged using power from a computer's USB port. A red LED indicator is lit when the unit is connected and recharging.
The A1 amplifier is pretty light... less than 3 oz for the electronics, the external battery, and case.
For the FirstUse review, we will charge up the unit and hook it up to a few players and headphone to see how this unit performs. It will be interesting to see if this amplifier can drive the larger high fidelity stereo headphones we use for our home stereo system and not just the ear buds that we use with the portable devices.