Compressor Switch (12 Band); Low Band Rotary Control (12 Band) - TRACE ELLIOT AH1000-12 Guide D'utilisation

The compressor in the 7 Band series uses studio quality, dedicated dynamics controller integrated
circuits and has been specifically designed for bass guitar due to the common problems often
experienced when using a normal, single band compressor in this application.
With a standard compressor, the transition from non-compressed to compressed, i.e. crossing the
threshold, can often be abrupt and unnatural sounding, especially at high ratio settings. Also, the
normal pre-set attack and release times always have to be a compromise between having it work
fast enough to catch rapidly changing signal levels (i.e. transients such as slapping techniques) or
too fast which can cause low frequency distortion.
To tackle these issues, the compressor on the 7 Band range has been designed as a soft-knee
compressor with programme dependant adaptive attack and release times.
➢ Soft-knee means that, above the threshold, compression is applied gradually, with the ratio
increasing as the input level goes up. The result is a smoother sounding compression than the
normal hard-knee type.
➢ Adaptive attack and release means that these settings are automatically and constantly adjusted
by the circuitry depending on what is being played. It will adjust to be slow to prevent distortion
at low frequencies and then readjust to be fast to catch transients. It enables a bass player to
switch between various playing styles such as finger style, slapping or plectrum, and the
compressor will self-adjust its attack and release times accordingly.
The simple single control makes setting the desired amount of compression easy as it is effectively
controlling the threshold, ratio and make-up gain simultaneously.
complicated than setting up a studio compressor from scratch as most of the hard work has been
done by our engineers and incorporated into the circuitry.
The circuit has been tuned so there should be little nominal signal level difference when switching
the COMPRESSOR on and off, however this is dependant on the correct setting of the INPUT
GAIN control. If you find that the level increases too much when switching the COMPRESSOR
on, then slightly turn up the INPUT GAIN. The opposite applies if the compressed sound is too low.
Compression is good for generally controlling the dynamic range and preventing distortion, and
also as an effect. It sounds great for slapping techniques, for making harmonics more prominent,
and for fattening up grooves or smoothing out notes in a run.
Please be aware that due to the nature of any compression circuit that then adds make-up gain to
bring the nominal level up, dialling in high levels of compression will increase high frequency hiss
between notes. This is not hiss added by the compressor circuit, but hiss that is already present in
the signal and then being amplified. However, as this is only really noticeable when not actually
playing, if high levels of compression are desired it is possible to prevent the noise from being heard
too much by using the footcontroller to turn off the compression or muting the signal when nothing
is being played.

(14) COMPRESSOR switch (12 Band)

Pressing the switch will add the dual band COMPRESSOR to the signal chain. The blue LED
above the switch shows its status. It can also be switched on and off using the supplied
footcontroller.

(15) LOW BAND rotary control (12 Band)

This adjusts the amount of compression applied to the low frequencies in the signal; the further
clockwise the control is set, the more the dynamic range of the low end will be squeezed.
12
This is considerably less