Wisdom in mind,   enthusiasm at heart.

NFB-15(Version 2014 )(Since 20th May 2014)

Discrete  DAC+ Headphone amplifier / Preamplifier
32bit / 384K Asynchronous Transfer  USB-32 Chip
Built in 2 Pieces Hi-end grade WM8741 Chips

The rule of the power ON /  OFF:
Power On :
     Source power ON ---->    NFB-15 power ON ----> Amp power ON
Power Off:
    Amp power OFF ---->  NFB-15 power OFF   ---> Source power OFF .

 How to set the NFB-15 DAC output as variable line level only?
    The NFB-15 has one group Line out for dedicated DAC output, In default its output level setting is at variable model . But owners can set it to can select between variable and fixed or output variable line level only . See the photos, change the jumper to "variable" side to set the DAC output to variable only.

         

 The NFB-15 Functions:

     Front plate:
     Output switch: Select output between headphone, Fixed DAC output and Variable DAC output.
     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.
     Selector 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. (The DAC output level can be chosen between variable and fixed, see below).

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 .
　

9 types digital filter users setting.
　

Please note:
    
     In 4X oversampling setting ,while select SPDIF input but without input signal, maybe output some noise.
     If the input sampling higher than the NFB-15 setting sampling, maybe cause some noise output.

8X oversampling , Minimum phase apodising filter.
Up to 48KHz support.  

8X oversampling , Linear phase apodising filter.
Up to 48KHz support.  

8X oversampling , Linear phase half-band filter for backward compatibility.
Up to 48KHz support.

 4X oversampling , Minimum phase 'soft-knee' filter.
Up to 96KHz support.

4X oversampling , Linear phase 'soft-knee' filter.
Up to 96KHz support.  

4X oversampling , Linear phase 'brickwall' filter.
Up to 96KHz support. 

2X oversampling , Minimum phase 'soft-knee' filter.
Up to 192KHz support. 

2X oversampling , Linear phase 'soft-knee' filter.
Up to 192KHz support.

2X oversampling , Linear phase 'brickwall' filter.
Up to 192KHz support.