How to choose the output models in Master-8 : 
                     Master-8 have a switch on rear can select between high power model and low power model base on different headphones request . ( Before select , Must power off and waiting least 10 seconds ) , both models are working on without "switch distortion" Class A state.
                     Master-8 have a switch on rear can select the gain boost on XLR and RCA input model for some low output level source can cooperate with Master-8 perform high power output. ( Before select please lower the volume at first )

How to choose the settings in Master-8 :
   With the Master-8, the user has a choice of 70 steps ( Linear characteristic ) and 99 steps ( Exponent characteristic) of volume control, and you can also choose whether to have volume memory.
1. Choose 70/99 steps volume control:
Step A: Push out the "Debug" switch.
Step B: The display shows as pictures below.
Step C: Push the volume button, choose between 70 or 99 on right.
Step D: Push in the "Debug" switch.
                                             70 step volume control                                         99 step volume control
             
2. Choose volume memory:
Step A: Push out the "Debug" switch.
Step B: Push the selector button; the display shows as pictures below.
Step C: Push the volume button, choose display "ON" or "OF" on left.
Step D: Push in the "Debug" switch.
                                               Volume memory active.                                        Volume memory off.