This Source Audio Atlas Compressor features a blend control that lets you mix your dry and compressed signals, retaining the natural dynamics of playing. This transparent compressor also features a ratio control which allows you to adjust the amount of compression to your signal, while the attack and release controls fine tune the response of compression. The original box is included. This Source Adio Atlas Compressor is in Very Good condition and fully function. There is a small blemish to the top finish and Velcro is on the bottom. The power supply is not included.