GreenKey

USB Isolator. Get clean USB signal !
No Zzzz, Mmmm or Buzzz anymore in your sound.

The Firestone Audio GreenKey is a USB Isolator and is designed to solve electrical noise problems, coming through a USB connection of a computer that can influence the audio signal. The most important part of digital audio is the clarity of the data travelling along the USB cable. Since the very beginning of PC based audio, the noise from the power lines has effected the data integrity creating problems with the timing of the digital signal, known as jitter. With the growing popularity of digital music via the humble PC, jitter has become the primary source of 'digititus', and the GreenKey will help reduce that interference substantially by isolating the power from the connection to the DAC.
The green Key works Plug & Play with any Mac, Windows PC and Linux PC.

Important :
The greenkey will not cut off USB voltage 5VDC, but however will limit the current draw !
As result, the GreenKey can only be used with USB equipment that has it's own external powersupply. As example we tried : A USB memory key will work (low current draw), an external Hard Drive with moving harddisk will not work. (high current draw). Of course this has nothing to do with audio equipment, but just to give you an idea.

Specification