Pendulum OCL-2 Operating Manual

Pendulum OCL-2 Operating Manual
OCL-2 Vacuum Tube Compressor/Limiter-

Operating Manual

Features
·Fast electro-optical input attenuator with an all tube gain stage
·Soft-knee design with fully adjustable compression ratio
·Transformerless high voltage class A signal path
·Low noise, wide bandwidth and superior transient response
·Custom optical cells matched for precise stereo balance
·Three sidechain operating modes: Fast, Presets and Manual
·Two completely independent channels with stereo linking
·Hard bypass switches for each channel
·Sidechain inserts for frequency-dependent compression and de-essing
·Transformerless output stage capable of delivering +35dBu
·Soft-start warm-up with output muting
·Gold-plated switch contacts, I/O connectors and tube sockets
·Fully regulated high voltage (300V), filament and bipolar power supplies
·Custom toroidal power transformer with shield for minimum hum
·Polypropylene capacitors and metal film resistors
·Single-sided audio pc boards to minimize capacitive interaction
Introduction
Thank you for purchasing the Pendulum OCL-2, a modern two channel
electro-optical compressor/limiter designed for the utmost in transparency, detail
and versatility. Our short signal path design uses a custom optical input
attenuation network in front of an all tube class A gain stage. Since the signal
path is entirely transformerless, we've eliminated the coloration inherent in
traditional transformer-coupled tube designs. The result is an open, detailed
sound with an expanded sound stage and clarity that can only be achieved with
modern tube circuitry.
The OCL-2's soft-knee design offers smooth, effortless dynamic control with the
ratio adjustable from light compression to limiting. Our unique sidechain circuit
linearizes the optical gain element to reduce distortion, and achieves much faster
attack and release times than encountered with conventional optical compressors.
Stereo linking is accomplished with the flip of a switch .
For maximum versatility, the OCL-2 has three modes of dynamics processing: In
the FAST mode, the compressor works as fast as the optical element will allow,
and is remarkably free of the 'pumping' artifacts normally encountered with
slower optical compressors. It's the ideal choice for invisible dynamics
processing, either for tracking or tight program compression.
The PRESET mode consists of six classic attack/release time settings that are
optimized for program compression, including two settings with
program-dependent release times.
The MANUAL mode offers total control over the attack and release times, which
is particularly useful for creative compression effects or for processing bass
guitar.
Most important, the hard bypass switches on the front panel conveniently allow a
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