Lexicon PCM92 manual Signal Type, Spread Early Spread, Tail Width, Tap Slope

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Signal Type

Selects the type of signal to be created by the signal generator. The types of signal are:

Sine Wave — When this is selected the signal frequency parameter is used to control frequency.

Sweep Up — 20Hz to 20KHz sweep. When this is selected the signal rate parameter is used to control rate.

Sweep Down — 20Khz to 20Hz sweep. When this is selected the signal rate parameter is used to control rate.

Pink Click — Broadband impulse. When this is selected the signal rate parameter is used to control rate.

White Noise (correlated) — sends identical white noise to all outputs

White Noise (decorrelated) — sends decorrelated white noise to all out- puts.

Pink Noise (correlated) — sends identical pink noise to all outputs

Pink Noise (decorrelated) — sends decorrelated pink noise to all out- puts.

Spread (Early Spread)

The spread parameter is closely tied to the Shape parameter. Spread is a win- dow of time during which a signal is injected into the reverb. Shape controls just how the signal is injected during this window.

Tail Width

This parameter is present in all stereo reverbs and rooms. The reverb tail (all components of the reverb except for early reflections, etc.) is passed through a simple 2x2 matrix. This provides an encoding of the tail that dramatically changes its spatial characteristics. The tail can be changed to feel narrower (even down to mono) or wider than normal stereo. There are values for the parameter to encode the tail in such a way that it decodes into surround channels.

The parameter operates in the range of 0 to 360 degrees, with an incremen- tal change of 1 degree. The matrix uses Sine/Cosine rules so that power dis- tribution remains constant. This may be acceptible—even highly desirable— but the mix engineer must fully understand the process and its implications.

This is a powerful tool for audio whose release format is two-channel. It is not useful in any other format. Formats include compact disc and radio/tele- vision broadcast. Some of these effects are clear and noticeable without any sort of decoder. Many are even more dramatic when a decoder is in place, such as in a home theater.

Tap Slope

This is an extremely subtle parameter and is useful in only a couple of cases:

For halls and reverbs with relatively long reverb times, the slope should be slightly positive (0.2 or so). For rooms with very short reverb times, the slope should be slightly negative (-0.2 or so).

Using a reverb to create a gate effect or to create a pseudo-room sound. MidRT should be at 0. Spread should be fairly high. Shape should be fairly high. Size should be fairly high. TapSlope should be in the range of (0.5 to 1.0). Play with spread, shape and size to vary the effect.

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Contents Page Important Safety Instructions Declaration of Conformity Warranty Overview of TCP/IP Basics Midi SysEx Implementation Introduction Page Front Panel Load BackRear Panel Power JackEthernet Input AES/EBU In/OutPage Using the PCM92 1Single Stereo Config1SinglConcertHallStereo-FlaCongefig4896 To select a different category Category Selection Screen System Presets1ConcertHall-Flange 0Med Hall Save As Single Stereo Config Page DSP Configurations Networking Subnet Mask 255.255.0.0 Gateway Dhcp Support EnabledDhcp Network Considerations and Limitations System Menu Audio SourceClock Source Analog Setup AES SetupClock Rate Base Channel Device IDMachine Bank DumpTempo Source Machine MenuWet Dry Mix Input LevelUsing Midi Soft Row Parameter Channel Usage DescriptionByte Definition Comments Bank Presets Bank #0xF0 Sysex message 0x06 Page Algorithms Hall Stereo and Mono Random Hall Stereo and Mono Resonant Chords Stereo and Mono Chorus/Flange Stereo only Page Bandwidth ParametersBass Boost Room Bass Crossover BassXOverDelay Level Master Delay Feedback MasterDelay Time Echo Delay Delay Time MasterFeedback Diffusion Master Echo DelayFeedback Level Feedback PanReflection Delay Delay Time Master Reflection Delay Reflection Time MasterMidRT Mix Wet Dry MixReverb PreDelay Predelay Resonance Tuning MasterResonance Master Resonator DetuneSignal Frequency Signal Event FreqRtHC Damping ScaleSpread Early Spread Signal TypeTail Width Tap SlopeWet Dry Mix TypePCM92 Menu Navigation Map System View and Machine View PCM92 Menu Navigation Map Stereo Hall Algorithms PCM92 Menu Navigation Map Stereo chamber and room Algorithms PCM92 Menu Navigation Map Stereo Delay Algorithms PCM92 Menu Navigation Map Stereo Effects Algorithms PCM92 Menu Navigation Map Mono Hall Algorithms  Menu Navigation Map Mono Chamber and room Algorithms Menu Navigation Map Mono Delay Algorithms Menu Navigation Map Mono Effects AlgorithmsPage 44.1 kHz 48 kHz 88.2 kHz 96 kHz PCM92 Specifications44.1K/88.2K Storage MediaFCC Midi Implementation Chart Page PCM92