Wisdom in mind,   enthusiasm at heart.

NFB-6
Fully Balanced discrete Preamp / Headphone amp
5500mW @ 50 ohm output

The rule of the power ON /  OFF:
Power On :
     Source power ON ---->    NFB-6 power ON ----> Amp power ON
Power Off:
    Amp power OFF ---->  NFB-6 power OFF   ---> Source power OFF .

Front plate function:

HP/PRE: Select the output modes of the NFB-6. H mean  headphone output, P mean  Preamp output.
GAIN:Select the high / low gain mode for NFB-6. For better sound quality design, the IN 3 (ACSS) always on the high gain mode.
Input:Select the input source for NFB-6.   
Volume + and -:Push once to adjust volume up and down in single step for NFB-6. Push and hold to adjust volume up and down continuously .