Wisdom in mind,   enthusiasm at heart.

NFB-11(2015 )(Since 1th Feb 2015)

Discrete  DAC+ Headphone amplifier / Preamplifier
DSD , DXD support from USB
32bit / 384K Sabre ES9018
32bit / 384K Asynchronous Transfer  USB-32 Chip

The rule of the power ON /  OFF:
Power On :
     Source power ON ---->    NFB-11 power ON ----> Amp power ON
Power Off:
    Amp power OFF ---->  NFB-11 power OFF   ---> Source power OFF .

Please note:
      The NFB-11 built in high biase current amps , for most headphones at normal listen volume it is working at class A state , so working long time will become a little warm, there is better keep it have good are follow state .
      The NFB-11 must install the driver for Windows USB connect. Mac OSX , Linux and SPDIF without driver install necessary .

How to set the NFB-11 DAC output as variable or fixed level ?
   The NFB-11 has one group  dedicated DAC output, In default its output level setting is at variable model and fixed model . If users only want the variable model only , change the jumper as below picture .
      (Be care, if the NFB-11 DAC output connect to a non volume control amp , don't turn to fixed output model , or setting to variable output model only . The headphone output always have volume control. )

 The NFB-11 Functions:

     Front plate:
     Output switch:        Select output between headphone and DAC output ( Variable level) and DAC output ( Fixed level).
     Gain switch:           Select gain between low gain (+0DB) and high gain (+12DB).
     Volume knob:         Control the volume level of the headphone and variable DAC output.
     Input switch:           Select source between USB, coaxial and optical.   

     Rear:
     Power socket:          For power input and power ON/OFF switch.
     USB socket:            For USB input.
     Opt socket:              For optical input.
     Coax socket:           For coaxial input.
     DAC out sockets:    For dedicated DAC output. DAC output ( Variable level) and DAC output ( Fixed level).
     Mute switch :  Push 1 for active the mute design, Push 2 for suspend the mute design.

Please note :
      Before shipping we had double check the gear have the perfect state of the outside . 
        Few countries customs workers is rude maybe scrape the chassis or volume knob while custom check , if the scrape have not effect the performance , customers can pay the shipping cost for ask we send the free parts for replacement .
        If the volume switch broken during rude custom check , there is a spare volume switch in the pack for customers replace by themselves , this is had not soldering necessary .
        In our experiences , scrape chassis or shatter the volume switch is very infrequent ( In case less than 1%).
        The product had include shipping insurance , if had any damage , can ask the express company make the compensation .