Lexicon 960L owner manual Using the Reverb Programs, Reverberation and Reality

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960L Owner’s Maunal

Using The Reverb Program

Using the Reverb Programs

Music recorded in a typical studio sounds dull. In a performance space the music is enhanced by reverberation, but even in an ideal space capturing that reverberation can be chancy. Lexicon reverberators solve this problem by enabling you to generate exactly the reverberance that your recordings call for, even with multitrack originals made in imperfect spaces. You can make your listeners feel they are sitting in a real concert hall, even though they are in a small room with hard, flat walls. The object of the 960L is to create, in the studio, the acoustics of any real or conceivable space, and to reproduce these acoustics using the full directional capabilities of a modern surround system.

Reverberation and Reality

The acoustics of a given space are defined by its reflected energy – that is, the way sound is reflected and re-reflected from each surface. This is affected by the dimensions of the space, the complexity or flatness of the surfaces, the frequency characteristics of each surface’s energy absorption, and the distance and direction of each surface to the listener. In addition, in large spaces there is a high-frequency rolloff caused by the sound’s passage through air.

It is in principle possible to model the reflected energy pattern in a specific space, either real or imagined, and to reproduce this pattern as closely as possible through a five-loudspeaker array. Alternately, one could measure the reflection pattern from a specific source point in a real space to a specific receiver position, and reproduce this pattern through five loudspeakers. One might expect this technique would yield the most accurate sonic representations of halls and rooms.

Alas, the illusion of reality is not so easily achieved. First, real spaces are themselves a compromise. Small rooms (and stage houses) tend to provide a sense of blend and distance to music, but provide little warmth and envelopment, and often can make the sound colored or muddy. Large rooms can provide envelopment, but often the sound can be too clear and present, with the instruments seemingly stuck in loudspeakers.

To make matters worse, in a real space every musician will have a completely different reflection pattern from every other musician, and every listener will have a different pattern from every other listener. In addition, reproduction of a given sound field through a loudspeaker array is only possible if the listener occupies a single, known position. If our goal is to create a believable room impression over a wide listening area – and this should be our goal – then we better do something else.

Our solution has been to study the physics and the neurology of human hearing, to discover the mechanisms by which reflected energy patterns create the useful perceptions of distance and envelopment, and to discover how to recreate these perceptions without compromising clarity. Using a knowledge of these mechanisms we can create reverberation devices that can give the desired acoustic impressions – rooms that sound plausibly real, but that give the recording engineer complete control over the sense of distance and the sense of envelopment. These rooms seem real, but they are not. They are designed and adjusted by the engineer to the specific needs of the recording, and they create their magic uniformly over a wide listening area.

To see how this works, consider a concert space – a large hall. In this space we hear a sonic event as a whole package of sounds, consisting of direct sound, various early reflections, and finally the reverberant tail. The sound that reaches us directly from the performer tells us the horizontal (and possibly the vertical) direction of the sound source; the reflections that follow give us cues for determining the distance to the source, and give us some information about the space.

Yet describing acoustics through the concepts of direct sound, early reflections, and reverberation is misleading from the point of view of human perception. Direct sound, early reflections and reverberation are only meaningful when the sound source is a very short impulse, like a pistol shot. Real sound sources produce sound events of finite duration (notes). The duration of a note is typically longer than the time between the direct sound and the early reflections. The length of time a note is held dramatically changes the acoustics we perceive, as short notes excite primarily early reflections, and long notes excite the later reverberation.

For example, in real rooms the direct sound is primarily perceived at the onsets of sound events (notes.) When a sound starts abruptly there is a brief instant where we can hear the direct sound all alone, before it is corrupted by or overwhelmed by reflected energy. In this brief interval we can detect the direction, and sometimes the elevation of the source. The so-called "early reflections" are only audible after a note starts. They are sometimes audible as a change in localization or timbre while a note is held, but in general they affect perception most strongly only after a note ends. These reflections are heard in the space between notes – and then often only as a tendency to make the notes sound longer than they actually are. Reverberation also is nearly always heard after the ends of notes, either in the space between notes, or at the end of whole

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Contents 960L. Digital Effects System Important Safety Instructions Table Of Contents Table Of Contents Introduction Title of SectionMainframe Description Rear PanelAbout the 960L Unpacking the 960LClock Card Midi Connectors Five-pin DIN female Remote-Control ConnectorsMains Power Switch IEC Power ConnectorStandby Switch and Indicator Front PanelFloppy Drive ThumbscrewsBehind the Front Panel DSP-Card SlotsCPU Card Installation MountingVentilation LocationDigital Audio Connections Midi ConnectionsWordclock Connections LARC2 Remote Navigating Typical Display ScreensLARC2 Remote About the LARC2Unpacking the Larc LARC2 Control Surface LARC2 Control SurfaceGetting What You Want LARC2 ConnectionsNavigating Typical Display Screens A typical display screenMode Faders Joystick About the Faders and JoystickAudio Indicators Fine AdjustLexicon Button Basic Operation AN Overview of the ControlsBasic Operation An Overview of the ControlsSetup Control Mode Quick Guide to Operation960L Owner’s MaunalBasic Operations Quick Guide to Operation Machine Selection Program LoadingEditing a Program or Register Storing Your EditsName screen Info screens are similar Control Mode CLOCKS, Configuration Operations in DetailLoading Programs and Registers Loading ProgramsLoading Registers Alternative Loading TechniquesProgramming Machines Control Mode Clocks, Configuration, and System Screens WordclockInput, Output, and Machine Configuration Locked and unlocked wordclock960L Owner’s Maunal Operations in Detail 44.1/48kHz Dual machines 5-in and 2-in Output Assignment Left Right Center Unused Surround Surround Analog and Digital I/O System ScreenFine Adjust EditingEditing Algorithms Editing With the FadersEditing with the Joystick Quick Comparisons via the Lexicon ButtonEditing Inputs and Outputs Input PanningOutput Panning Setting Levels 960L Surround Panning RulesAvoiding Overload Using the Edit Algorithm Screen V-Page and Parameter ReassignmentFrom the Edit Algorithm, Inputs, Outputs Options screen 22 Edit V-Page screen programming the joystick Storing and Labeling Your Edits StoringNaming and Annotating 25 a Register Info Options Enabled Organizing Your RegistersMachine Mode Using the Floppy DriveCD-ROM Edit Tools for RegistersUsing the Reverb Programs Using the Reverb Programs Reverberation and RealityUsing The Reverb Program Lexicon, Inc Reverberation and Reality Msec Sound in Space a Short History of Stereo and Surround Algorithms Random HallSurround Hall ChamberPlate & Surround Plate Ambience & Surround AmbienceAmbient Chamber Reverse & Surround ReverseInverse Parameters Used in the 960L Algorithms Using The Reverb ProgramLexicon, Inc FbckL FbckRFbckLF FbckLSLvLL LvRRLvLR LvRL LvLFLFRearRoll RearRvbRShape RSpreadSize SlopeSpin SpreadMidi Nomenclature Midi Channel AllocationChannel Usage Description Card Configuration Bank and Program MappingBank Description Program # DescriptionMidi Sysex Incoming Inquiry Midi Byte Description960Ls response Midi Implementation Chart Specifications Specifications Connector 48K Rack Units96K Factory ProgramsLARC2 User Interface Appendix Appendix Program Descriptions HallsAppendix B1 P4 B3 P4 B6 P2 B7 P2 B9 P9 B11 P5 Empty Mini Chamber Similar to Snare Chamber, but even smaller Lg Brite Room Random Hall Simply large and bright Echo Plate Like Flat Plate, but with echoes Stereo Bank Kitchen Chamber Can you find your disposal sound effect?
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