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1)   The 518 can be set up for 4 different functions:    TYPE 0 - simple pre-amp in a digital audio system    TYPE 1 - resolution enhancement processor    TYPE 2 - mastering processor    TYPE 2 - multimedia processor 2)   Check unit processor version:    On power up, press and hold DSP button whilst switching power switch ON    Version will be displayed, earlier version is 1.14, later version is 1.22 3)   Check TYPE setting:    Press and hold SOURCE button, switch ON power at rear, display will show which TYPE unit is set to 4)   Operation as TYPE 0:    Pressing SOURCE will take the 518 out of standby    Select SOURCE by pressing button until desired input is displayed    Adjust VOLUME up or down as desired    Each volume number represents approx 11% change in loudness; 9 steps to double loudness    Unity gain setting (0dB) is at volume number 87    Select output word option by pressing OUT until desired selection made    Select input word option by pressing IN until desired number of input bits to be read is selected Generally the 518 should be set so that the input and output word lengths match the input signal and the equipment following the 518    Select dither options by pressing DITHER until desired option selected    FLAT - white spectrum, TPDF dither    HP - high pass, additive TPDF dither    SHAPE A - flat dither with 2nd order shaper to MAF *    SHAPE B - flat dither with 9th order shaper to MAP **    SHAPE C - flat dither with 9th order shaper to MAF    SHAPE D - high pass dither with 9th order shaper to MAF    SHAPE E - high pass dither with 2nd order shaper to MAF    (* Minimum Audible Field - appropriate threshold curve for listeners with normal stereo speakers)    (** Minimum Audible Pressure - appropriate threshold curve for listeners using headphones) Noise shaping works by an averaging method that is well matched to human hearing. The noise-floor of the system is shaped by moving energy from the mid-range (the most sensitive for listeners) to high frequencies. With correctly designed noise shapes the noise of the channel will be made inaudible and thus allow resolution that is well below the normal wordsize DITHER is an essential part of digital audio if processing is to remain transparent. Transparency in a digital signal is the result of maintaining linearity at both high and low levels and not falling prey to signal-processing distortions (eg noise modulation) NOISE SHAPING is a technique where the noise is moved from the the spectral regions where the listener is sensitive to other regions where they are less audible    SIMPLE RULES for using the 518:    STEP-DOWN IN SAMPLE WORD SIZE:    20 bit masters to 16 bit carrier (ie CD)    GAIN to bring peak level as close to full scale as possible    PRE-EMPH if program material permits    SHAPE B, C or D (unless significant subsequent editing, then SHAPE A or high-pass dither)    NO CHANGE IN SAMPLE WORD SIZE:    GAIN to bring peak level as close to full scale as possible    PRE-EMPH if program material permits    SHAPE A or HIGH-PASS dither    STEP-UP IN DYNAMIC RANGE:    PRE-EMPH if program material permits    SHAPE A or HIGH-PASS dither    Select primary processing mode by pressing DSP    GAIN - flat frequency response with signal level adjusted by precision dithered multiplication    EMPH - output of 518 always pre-emphasised (providing incoming signal is not already pre-emph)    DE-EMPH - use only if DAC can provide digital de-emphasis (ensures 518 o/p is never pre-emph)    Select display format by pressing DISPLAY    EMPHASIS light indicates when incoming audio is pre-emphasised    CLIP message indicates if overload on Left, Right or Both 5)   Restoring default settings:    With the 518 switched OFF, press SOURCE button, swith ON power, display will read TYPE 1    Release SOURCE button    The type can now be changed using the UP/DOWN buttons on the far right    Switch OFF using the power switch at the rear    WAIT 1 second, switch power back ON again 6)   Customising TYPE or CONFIG:    Switch the 518 OFF    Whilst pressing specific button, switch power ON at rear    TYPE - press and hold SOURCE    CONFIG - press and hold DISPLAY    NORMAL - do not press any button    Release button Return to HOME page   All trademarks and rights belong to the OEM and are reproduced here for information purposes only

 

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