TL Audio 5021 - Manual (Page 5)

1 INTRODUCTION
Congratulations on purchasing the Ivory 2 5021 Dual Valve Compressor by TL
Audio!
The Ivory 2 Series consists of a range of hybrid valve signal processors, which
utilise low noise solid-state electronics in conjunction with classic valve
circuitry to produce audio processing units offering very high quality signal
paths with the unique valve audio character. The Ivory 2 Series units offer
comprehensive control facilities, whilst remaining straightforward to operate,
and represent excellent value for money.
The block diagram of the 5021 is shown in Figure 1. A solid state,
electronically balanced input amplifier is used to achieve state of the art
performance with very low noise, low distortion and wide bandwidth. An
ECC83/12AX7A triode valve stage (run from a stabilised 150v DC supply) is
used as a second stage voltage amplifier, to obtain the classic valve sound
and gradual overdrive characteristics. Like all other TL Audio compressors, the
gain control element of the 5021 is based around a special transconductance
amplifier, which avoids the use of VCAs and helps contribute to the smooth,
open sound of the unit. A second ECC83 valve stage forms part of the
compressor gain make-up circuit.
The 5021 has both line and instrument inputs, a compressor (with variable
controls) and a noise gate. Two illuminated VU meters monitor the output level
or the gain reduction. The optional DO-2 digital card allows 24-bit A to D
conversion via an RCA phono type SPDIF output, with selectable 44.1 or 48
kHz sample rates and the option to clock the converter to an external word
clock source.
Line inputs and outputs are provided on electronically balanced XLR
connectors and on unbalanced mono 0.25” jack connectors, both of which can
be used simultaneously. The operating level of the inputs and outputs can be
shifted by 14dB from -10dB to +4dB (for the unbalanced connectors) or +4dB
to +18dB (for the balanced connectors) via a rear panel switch, enabling the
5021 to be used with the latest generation of digital recorders - which generate
very high signal levels. A front panel instrument input is also provided, thus
allowing guitars, basses and keyboards to feed directly into the 5021,
removing the need for a separate DI box.
The compressor sidechain connectors on the rear of the 5021 can be used to
connect an external processor such as an equaliser into the compressor
circuit. This allows the compressor to effectively become frequency conscious,
as the compressor then becomes more sensitive to any boosted frequencies
on the equaliser. A typical application of this would be to “de-ess” (remove
sibilance) from a source by boosting the sibilant frequency on the side-chained
equaliser.
Please read this manual fully before installing or operating the 5021.