The F388-2-Q is a 19 Inch, durable, powerful, headphone amplifier with two + two balanced stereo inputs on the back. It features 4 identical amp sections each with individual volume and balance control. The stereo signal from module 1 can be looped through to module 2 with a link switch. The internal Pre-Gain can be set to -12 / -6 / 0 / +6 / +12 dB to adapt the amp to virtually any source or headphone combination. The amplifier features low output impedance to drive low-impedance headphones without coloration and has a high internal operating voltage to supply high-impedance headphones with what they need.