The Lexicon PCM81 is a 2-in/2-out studio and live sound multi-effects processor in a 1U rack unit. Lexicon describes it as a unit that "maintains Lexicon's highest standards for sonic clarity, and its extraordinary processing power yields the finest effects available in its price class, plus outstanding reverberation"1. It takes where the PCM80 left off, adding AES/EBU digital I/O, the algorithms and presets from the Pitch FX and Vocal Fix Cards, and 24-bit converters for higher quality audio1.
The PCM81 is discontinued. Lexicon lists it as a past product, with its specifications still published on the maker's site1.
What the PCM81 adds over the PCM80
The PCM81 is the successor in Lexicon's PCM line. Where the PCM80 established the platform, the PCM81 "takes where the PCM 80 left off"1. The three additions Lexicon identifies are:
- AES/EBU digital I/O alongside the analog connections
- The algorithms and presets from the Pitch FX and Vocal Fix Cards, built in rather than added as expansions
- 24-bit converters for higher quality audio1
The internal audio DSP is 24-bit on the PCM81, compared with 20-bit on the PCM91 that Lexicon lists alongside it1.
Power and connections: analog, AES/EBU and S/PDIF
The PCM81 runs on mains power rather than a pedalboard supply: 100 to 240 volts AC at 50 to 60Hz, drawing 35 watts, with automatic voltage switching through a 3-pin IEC connector1. That means no battery or 9V DC option; it is a studio or rack unit.
Analog audio is handled by XLR and 1/4 inch balanced TRS connections on both input and output1. Digital audio comes in and goes out two ways:
| Connection | Format |
|---|---|
| Digital input, XLR | AES/EBU, balanced |
| Digital input, coaxial RCA | S/PDIF, unbalanced |
| Digital output, XLR | AES/EBU, balanced |
| Digital output, coaxial RCA | S/PDIF, unbalanced |
MIDI runs on 5-pin DIN connectors for MIDI IN, THRU and OUT1. For hands-free control there is a 1/4 inch TRS connector for two independent momentary footswitches, with the system detecting normal-open or normal-closed on power up, and a separate 1/4 inch TRS connector for a foot pedal with 100Ω to 10kΩ impedance1. A remote power input takes a 2.5mm 9 volt AC supply, which is not included1.
Audio specifications
| Specification | Value |
|---|---|
| Input level | -2dBu to +20dBu balanced; -22dBu to 0dBu unbalanced |
| Input impedance | 100kΩ balanced; 50kΩ unbalanced |
| Output level | +18dBm balanced; +4dBm unbalanced |
| Output impedance | 125Ω balanced |
| Frequency response | 10Hz to 20kHz, ±.5dB |
| Crosstalk | -55dB, 10Hz to 20kHz |
| THD | <0.006%, 10Hz to 20kHz |
| Dynamic range, A/D | >105dB typical, 10Hz to 20kHz |
| Dynamic range, D/A | >98dB typical, 10Hz to 20kHz |
| Dynamic range, A/A | >96dB typical, 10Hz to 20kHz |
The line-level analog inputs mean a guitar plugged straight in will not drive the unit properly; a preamp or other level-raising device in front of it is the practical route. The balanced input impedance of 100kΩ is a line-level figure, not a high-impedance instrument input1.
Memory cards
The PCM81 has a PCMCIA card slot for storing and loading programs. The connector takes PCMCIA type I cards with 68 pins, supporting up to 1MB of SRAM, with attribute memory not required. The slot follows the PCMCIA 2.0 and JEIDA 4.0 standards1.
Operating conditions
The unit is rated for operating temperatures of 32° to 104°F (0° to 40°C) and a maximum humidity of 95% without condensation1. At 6.4 lbs (2.9 kg) and a single rack space, it fits a standard effects rack alongside other multi-effects units such as the Lexicon MPX 1.
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Questions
What is the difference between the Lexicon PCM80 and PCM81?
The PCM81 takes where the PCM80 left off. It adds AES/EBU digital I/O, includes the algorithms and presets from the Pitch FX and Vocal Fix Cards, and adds 24-bit converters for higher quality audio. The core 2-in/2-out multi-effects platform is shared between the two units.
Does the PCM81 include the Pitch FX and Vocal Fix card presets?
Yes. Lexicon states that the PCM81 includes the algorithms and presets from the Pitch FX and Vocal Fix Cards, so those expansion card sounds from the earlier PCM80 ecosystem are built in rather than requiring a separate card.
What memory cards does the Lexicon PCM81 use?
The PCM81 uses PCMCIA type I cards with a 68-pin connector, supporting up to 1MB of SRAM, with attribute memory not required. It follows the PCMCIA 2.0 and JEIDA 4.0 standards.
Can I use a guitar straight into the Lexicon PCM81?
The analog inputs are XLR and 1/4 inch balanced TRS line-level connections, with input impedance of 100k ohms balanced and 50k ohms unbalanced, and input levels from -2dBu to +20dBu balanced. It is a line-level rack processor, so a guitar needs a preamp or other level-raising device in front of it.
Is the Lexicon PCM81 still made?
No. Lexicon lists the PCM81 as discontinued. It remains available only on the used market, and Lexicon's product page still carries its full specifications.
