Lexicon PCM 81 - User manual

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PCM 81 Highlights
•World-class Lexicon reverb
•2 DSP engines including Lexicon’s proprietary LexiChip®
• 24-bit A/D, D/A, and internal processing
•300 presets; 50 user programs
•Studio-standard reverbs and effects including: Reverb
and six voices of Delay or Reverb, four voices of Pitch
Shift, and Vocal Fix for replacing out-of-tune melody
lines
•A single Adjust knob that automatically attaches to all
applicable parameters in factory tailored presets
•
PCMCIA card slot for program storage
•Optional cards for algorithms, programs and user
presets
•Pro and Go Modes: Go mode allows access to as many
as 10 handpicked parameters for any particular preset;
Pro Mode allows full access to an Edit matrix of as
many as 100 parameters
•Dynamic Spatialization: 3D effects processing
(compatible with surround sound systems)
•Up to 20 seconds of delay
•Balanced analog inputs and outputs (XLR and 1/4")
•S/PDIF and AES/EBU digital inputs and outputs
•Tap Tempo for instant setting of delay and modulation
times
•Full MIDI control

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PCM 91 Highlights
•World-class Lexicon reverb
•Dual proprietary LexiChip®DSP engines
• 24-bit A/D, D/A, and internal processing
•450 presets; 100 user programs
•Lexicon's "Greatest Hits" reverb algorithms, including
Chamber, Concert Hall, Random Ambience, Random
Hall, Rich Plate, and Split Chamber
•Keyword search for quick, intelligent sorting of presets
by alphabetical order or application
•Front panel Adjust knob automatically attaches to one
or more parameters in each factory tailored preset
•
PCMCIA card slot for program storage
• Pro and Go Modes: Go mode allows access to as many as
10 handpicked parameters for any particular preset; Pro
Mode allows full access to an Edit matrix of as many as
100 parameters
•Balanced analog inputs and outputs (XLR and 1/4")
•S/PDIF and AES/EBU digital inputs and outputs
•Tap Tempo for instant setting of delay and modulation
times
•Full MIDI control

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For over 30 years, Lexicon has been considered a pioneer in digital audio.With
more experience than any other manufacturer, it’s no surprise that the PCM
81 Digital Effects Processor and the PCM 91 Digital Reverberator represent
the most advanced systems in their class. Lexicon’s unique dual DSP platform
enables the PCM 91 to offer the highest quality reverb, and allows the PCM
81 to combine reverb with powerful, flexible effects. Professional digital inputs
and outputs (AES/EBU and S/PDIF) on both units, coupled with the legendary
“Lexicon Sound”, makes the PCM 81 and PCM 91 an essential combination.
Easy Operation
The PCM 81 and PCM 91 are as simple to operate as they are pleasurable to
listen to. Just load a preset and a useful parameter will become instantly
available on the Adjust knob. The next level was designed for professionals
who want to further customize programs, but lack the time to wade through
the myriad of available controls. In this mode, as many as 10 of the most
logical parameters in a given effect are easily accessible for customization. For
the sound designer, another mode allows access to the full Editing matrix
available in both units, as well as a user-assignable Soft Row in which to store
favorite parameters. It also provides access to the extensive modulation
capabilities of the PCM 81 and the dynamic reverb aspects of the PCM 91.
Digital Inputs and Outputs
The PCM 81 and PCM 91 feature professional AES/EBU and S/PDIF digital
audio input and output formats. S/PDIF coaxial and AES/EBU XLR digital
output connectors can be used simultaneously, doubling digital audio outputs.
Dynamic Patching
The PCM 81 and PCM 91 raise Dynamic Patching to a new level, providing
unprecedented control over the effects. Dynamic Patching gives these
processors a truly unique set of capabilities, from modulating sounds, to
producing unusual and ethereal spaces, to altering the attack and decay
characteristics of the sounds. With Dynamic Patching it is possible to exceed
simple modulation effects. The Dynamic Patching matrix maps data from 143
possible control sources to any effect parameter. These sources include 126
different MIDI controllers, as well as external sources such as footswitches
and footpedals. Internal controllers include Tempo (both internal Tap and
external MIDI clock), LFOs (Sine, Cosine, Square, Triangle, Pulse, and
Sawtooth), Time Switches, Latch, AR Generator, and Left and Right Envelope
Followers. Up to 10 patches can be created per effect. In a conventional patch
scaling configuration, modulation occurs between maximum and minimum
values. In the Dynamic Patching matrix, eight pivot points can be established
to create complex and interesting modulation paths.
Tempo Control
The PCM 81 and PCM 91 offer Tap Tempo control of delay lines as well as
several rhythmic variations on the tap. Tempo can be “dialed-in” in beats-per-
minute, MIDI clock can be generated from tap, or received via MIDI from an
external sequencer or drum machine. Tempo can also control LFO speeds and
time switches, allowing modulations to be synchronized with music.
Independent rhythmic values can be set for each parameter within the same
program. Tempos can be read as both rhythmic values and absolute time
values. The PCM 81 also offers more than 20 seconds of stereo delay.
Card Slot
The PCM 81 and PCM 91 are both equipped with an industry-standard
PCMCIA card slot, allowing users to store personal programs and setups on
cards. For the PCM 81, adding Lexicon’s Dual FX algorithm and specially
designed preset cards for the PCM 80 (compatible with the PCM 81)
increases its number of algorithms to more than 40 and presets to nearly 800.
PCM 81 Effects
The PCM 81 has everything that made the PCM 80 the top choice among
studio effects processors. In addition, it offers more effects, more algorithms,
and full AES/EBU input and output. Two digital signal processors; Lexicon’s
proprietary LexiChip®for reverb, and a second DSP engine to handle other
effects, create versatile effect combinations without compromising sonic
clarity. The PCM 81 offers more than all other processors in its class with;
24-bit internal processing, a true stereo signal path, balanced analog inputs and
outputs,AES/EBU and S/PDIF digital inputs and outputs, the power to combine
analog and digital outputs, extensive modulation capabilities, and 300 presets.
PCM 81 Sounds
The PCM 81 boasts an enormous selection of sounds. Each combines
uncompromised stereo reverb with several voices of additional effects. A full
complement of Pitch Shifters provides unique special FX as well as doubling,
quadruple tracking, Chorus, and Pitch Correction within a range of three
octaves up or down. With 300 presets, the PCM 81 allows instant access to
Pitch, Reverb,Ambience, sophisticated Modulators, up to 20-second
stereo Delays, and Dynamic Spatialization effects for 2-channel or
surround applications. Its presets were designed to accommodate a wide

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www.lexicon.com/pcm81
www.lexicon.com/pcm91
group of programs designed for a given application. There are 50 keywords in
total, including four user-definable groups of effects.
PCM 91 Reverb
Lexicon’s research into the physics of acoustics is embodied in the Random
Hall algorithm. Echograms of real halls have dispelled the myth of pre-delay
and early reflections. In actual spaces, there is no empty interval between the
arrival of direct sound and the maximum reverb density filled by early
reflections. Instead, ambience builds gradually, with diffuse and complex
reflections that do not color the timbre of sound like fixed-delay taps.
Random Hall’s unique Shape, Size, and Spread parameters control the build-up
and decay of the ambient envelope. Size determines how large the space will
be. Shape controls the contour of the ambient build. At its highest settings, it
provides an inverse envelope for effects and gating. Spread controls the
duration of Shape, setting the build-up and sustain. Precision filters provide
spectral control of reverberation time, and unique Spin and Wander
parameters add random movement ensuring smooth reverberant decay. In
the PCM 91, Lexicon’s classic Concert Hall algorithm has been enhanced
with Spatial EQ and a Compressor to increase its versatility. The Rich Plate
algorithm provides simulated plate reverberation, as well as new variations on
this classic effect. The Ambience algorithm provides effects tailored
specifically to the post-production environment, permitting accurate matching
of previously recorded ambience. This allows new elements to blend
seamlessly, and sound effects, dialog, or music to be placed realistically at
different positions in the "space." Each of the PCM 91 algorithms include
selected tools for ambience, post-processing, and compression/expansion, as
well as modulation and patching parameters common to each. Ten Dual
Reverb algorithms are built-in to the PCM 91. These algorithms contain two
independent reverb blocks to create superb Dual and Cascade-configured
stereo reverbs, each with all the control features of the single effects.
PCM 91 Custom Controllers
Control in the PCM 91 has been increased with the addition of four Custom
Controllers placed on the Soft Row. These controllers consist of one or more
parameters patched together, each with individual scaling values. Custom
controllers effectively add four more Adjust knobs to each program.
range of applications, from effects designed for musical uses and recordings to
effects designed specifically for pitch correction, sound effects, and video post-
production. The PCM 81 also features updated versions of classic Lexicon
effects such as Concert Hall and Tiled Room.
PCM 81 Algorithms
The PCM 81 utilizes 4-voice, 6-voice, and Pitch algorithms to create effects.
The 4-voice algorithms; Chamber, Concert Hall, Infinite, Inverse, and
Plate. Each combine a specific reverb type with a 4-voice stereo “effect
toolbox” called the Reverb Shell, which provides post-processing for the
reverb. For example, it is possible to produce a Ghost Flange by assigning a
Modulated Delay to an Inverse Reverb (to Detune it). The 6-voice algorithms;
Chorus + Reverb, Glide, Hall, Multiband + Reverb, Res 1 > Plate, and
Res 2 > Plate, combine a specific reverb type with a specialized
6-voice stereo effect. In these algorithms, it is possible to combine the
shimmer of a multi-voice chorus with a lush reverb tail (as in Wet Chorus).
The on-board Pitch algorithms encompass all Pitch and Vocal Correction
algorithms and effects available in the PCM 80 via plug-in cards. Seven
algorithms include Pitch Correct for correction of monophonic sources, and
Stereo Chamber for full stereo pitch-shifting with Chamber reverb. A
powerful submixer is built into the Dual Chamber, Dual Inverse, and Dual
Plate algorithms for flexible ordering and routing of two independent voices
of pitch-shifting with reverb.A 4-voice Quad > Hall algorithm provides four
independent pitch-shift voices with full stereo reverb, and a VSO-Chamber
algorithm provides stereo time and pitch correction with Chamber reverb and
variable speed pitch control (in percent).
PCM 81 Dynamic Spatialization
Two independent spatial processors accommodate the placement of effects
virtually anywhere between or beyond the loudspeakers. Effects can also be
located dynamically, creating different spaces that change with the music.
PCM 91 Presets
The PCM 91 includes 450 presets which provide sounds for real-world
applications. The most useful parameters of each sound are located in a user-
definable Soft Row, allowing users to make quick and simple adjustments.
Navigation is further simplified with labeled banks and rows.
PCM 91 KeyWord Search
A unique KeyWord Search function in the PCM 91 enables users to locate a

Analog Audio Input: XLR and 1/4” balanced (T/R/S)
Input Level: -2dBu to +20dBu, balanced;
-22dBu to 0dBu, unbalanced
Input Impedance: 100kΩ, balanced;
50kΩ, unbalanced
Analog Audio Output: XLR and 1/4” T/R/S balanced
Output Level: +18dBm, balanced;
+4dBm, unbalanced
Output Impedance: 125Ω, balanced
Digital Audio Input: XLR, balanced;
Coaxial RCA, unbalanced
Format: AES/EBU, balanced;
S/PDIF, unbalanced
Sample Rate: 44.1kHz and 48kHz
Digital Audio Output: XLR, balanced;
Coaxial RCA, unbalanced
Format: AES/EBU, balanced;
S/PDIF, unbalanced
Sample Rate: 44.1kHz and 48kHz
Conversion: 24-bit A/D; 24-bit D/A
Internal Audio DSP: 24-bit (PCM 81); 20-bit (PCM 91)
Frequency Response: 10Hz - 20kHz ±.5dB
Crosstalk: -55dB 10Hz to 20kHz
THD: <0.006%, 10Hz - 20kHz
Dynamic Range: D/A: >98dB typical, 10Hz - 20kHz
A/D: >105dB typical, 10Hz- 20kHz
A/A: >96dB typical, 10Hz - 20kHz
MIDI Interface: 5-pin DIN connectors for
MIDI IN, THRU and OUT
Footswitch: 1/4" T/R/S connector for two independent
momentary footswitches (system detects
normal-open, or normal-closed on
power up)
Foot Controller: 1/4" T/R/S connector for foot pedal
(100Ω- 10kΩimpedance)
Memory Card
Connector: PCMCIA type l cards, 68 pins
Standards: PCMCIA 2.0 and JEIDA 4.0
Card Format: Up to 1MB of SRAM
(attribute memory not required)
Power Requirements: 100 - 240 volts AC; 50 - 60Hz; 35 watts
(3-pin IEC connector)
Remote Power In: 2.5 mm 9 volts AC (not included)
Dimensions: 19" W x 1.75" H (1U) x 12" D
(483 x 45 x 305 mm), rack mount standard
Weight: 6.4 lbs. (2.9 kg)
Operating Temperature: 32° to 104°F (0° to 40°C)
Maximum Humidity: 95% without condensation
PCM 81
PCM 91
The PCM 81 and PCM 91 are each equipped with an industry-
standard PCMCIA card slot, allowing users to store personal
programs and setups on RAM cards. For the PCM 81, adding
Lexicon’s Dual FX algorithm and specially designed preset cards for
the PCM 80 (all of which are compatible with the PCM 81) increases
its number of algorithms to more than 40 and its number of presets to
nearly 800.