INTRODUCTION
The T L Audio Crimson Series utilises low noise solid state circuitry to produce audio
processing units offering very high quality signal paths with comprehensive control
facilities. The Crimson Series are straight-forward to operate and offer excellent value
for money.
The EQ-3011 is a two channel equaliser. Four bands of EQ are provided on each
channel, each with a switched or swept frequency selection to cover the full audio
bandwidth.
The block diagram of one channel of the unit is shown in fig.1. It has three input
sources - a balanced line level input via an XLR connector, an unbalanced line level
input via a jack socket, and an instrument input also on an unbalanced jack socket but
located on the front panel where it provides a convenient means of patching a guitar or
keyboard directly into the equaliser. All three inputs may be used simultaneously. The
gain of the input stages is controlled by a centre-detented control, calibrated for 0dB
nominal gain from the line input sources at the centre and pro/-20dB of
variation. The instrument input has a sensitivity switch associated with it, to match the
gain to a low level pickup (e.g. a passive guitar or microphone) or a higher output
source such as a keyboard or active guitar, followed by the 40dB variation of the input
gain control.
After the input stage, the signal is fed to the four equaliser stages, which are arranged
as shelving stages for the LF and HF, peaking (band pass) stages for the mid bands.
Individual stages are used for each band, to ensure minimum ineraction between
controls.
A variable intensity peak LED monitors the output of the equaliser stages, providing
an indication of the amount of drive and headroom available.
The signal chain is completed by an EQ-in switch plus balanced and unbalanced
output driver stages.
Please read this manual fully before installing or operating the Equaliser.