Meridian America Meridian 518 manual Part, Mastering Processor

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Using 518 for Mastering and Multimedia

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Part 2

Mastering Processor

The Meridian 518 Digital Audio Processor has been designed to allow the making of better recordings, and in particular to enable the production of high-quality, enhanced-definition CDs.

The predominantly available channels for delivering high-quality sound to consumers is stereo, linear-encoded 16 bit PCM. There is also no realistic prospect of a widely-available improvement on this capability. While CD is limited to 16 bits, we now have A/D converters, recorders and editors operating with anywhere between 16 and 24 bit words.

The Meridian 518 provides the very best quality and combination of signal-processing functions for use when preparing material for issue on media like CD. In fact, using the unique signal processing in 518, CDs can be produced with up to 19-bit subjective dynamic range.

The functions of 518 have been optimised for use in three stages of the production process, namely:

∙on location, processing the signal between the A/D converter and recorder,

∙during transfer of a recording to an editor,

∙during transfer from editor to production master.

In each such step, the word-size can be different, and 518 can make these processes optimal.

The signal-processing used is based on an extensive programme of research, and is implemented in DSP with an internal precision of 72 bits to ensure exceptional transparency. For a very full technical background, please see the papers referred to below: copies may be obtained from Meridian. 1 2 3 4

518 also finds applications in professional or consumer replay situations. Here the precision gain control and pre/de-emphasis processing can replace the system preamp and enhance the dynamic range of a D/A converter – see the earlier sections of this manual.

1J.R. Stuart and R.J. Wilson, "A Search for Efficient Dither for DSP Applications", 92nd AES Convention, Vienna 1991, Preprint #3334

2J.R. Stuart, "Noise: Methods for estimating Detectability and Threshold", 94th AES Convention, Berlin 1993, Preprint #3477

3M.A. Gerzon, P.G. Craven, J.R. Stuart, R.J. Wilson, "Psychoacoustic Noise- Shaped Improvements to CD and other Linear Digital Media", 94th AES Convention, Berlin 1993, Preprint #3501

4J.R. Stuart and R.J. Wilson, "Dynamic Range Enhancement Using Noise- Shaped Dither Applied to Signals With and Without Pre-emphasis", In preparation for AES Convention, Amsterdam 1994.

518 User Guide

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Contents 1992, 1993 Contents Appendix 4 -Resolution Enhancement Simple rules for usingAppendix 2 Hints on Mastering Acknowledgements Sales and service in the UKSales and service in the USA Designed & manufactured in the UK byConventions used in this manual IntroductionAbout this manual About the 500 SeriesConnections Installing yourGeneral precautions UnpackingWhats inside a 518? Planning setupOverview as Preamp Type What else do I need to know? What about analogue sources?CD or LaserDisc playback improvement Overview as Resolution Enhancement Processor TypeMeridian DSP speaker improvement Meridian Surround improvement Overview as Multimedia Processor Type Overview as Mastering Processor Type∙ Normal ∙ Standby ∙ Type ∙ Config Customising featuresStandby Switching onStarting off with Basic operationOut Adjusting the volumeOperating 518 as a Control Unit Type Selecting a sourceShape B DitherFlat Shape aDisplay Advanced operation using the Remote Control Menu Keys Operating 518 as Resolution Enhancer TypeVolume control Muting the soundOperation summary With the Remote ControlMemory Customising 518, an overview Restoring default settingsConfig an overview Config control settingsHow to change to Type or Config How to customiseCustomising, general procedure Config sources and inputsSetting Type Controller Customising using TypeHow to change back to Normal Making changes to an existing setupSelecting Types Customising using ConfigHow to use Config ConfigSetting the Standby mode for Selecting the controller modeSetting the system address for Setting the product address forSetting the Volume display Setting the Blank display option forSetting the Emphasis option for Setting the Volume mode forChoosing source logos Setting up sourcesVol. dB Choosing the Comms type for a source product Changing the input for a sourceChoosing the address of a source product Digital output connection ConnectionsDigital audio connections Digital input connectionsCon Connecting to Meridian Digital speakersCommunications connections To connect to other Meridian 500 Series equipmentMastering Processor PartD1 +2 DescriptionAs a Mastering or Multimedia Processor Type Meridian 500 Comms warningShpB +2 Emph +2Making Recordings Transfer to the final carrier Transfer to editorShaper Advantage 44.1kHz 48kHz Normal Pre-emphasis Noise shaper characteristicsDither Operating BackgroundTransparency in digital systems Digital Audio and QuantisationDynamic Range Noise Shaping with ditherPre and De-emphasis Step up in dynamic range Simple rules for usingStep-down in sample word size No change in sample sizeAdditional technical information SpecificationHelp Maintenance & Service CleaningNoise Part Appendix 1 Noise ShapesAbove noise spectrum for Shape B at 44.1kHz 0Hz 5kHz 10kHz 15kHz 20kHz Requirements for D/A conversion Vulnerability of the signalAudible results of digital errors and editing Appendix 2 Hints on Mastering with noise-shapingAppendix 2 Hints on Mastering Handset Functions Appendix 3 RS232GoTo Functions Jitter and de-jittering Appendix 4 -Resolution EnhancementFrequency Dynamic-rangeDynamic-range optimisation with Pre-emphasis Dynamic-range optimisation with GainShowing CD pre- and de-emphasis curves Dynamic-range optimisation with Noise-shaped Dither DAC or channel enhancement by word-length matching DAC enhancement by using high-frequency ditherIndex ContentsIndex User Guide User Guide
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