TL Audio A3 - Manual (Page 16)

15
Knee .
The Knee switch enables the Ebony A3 to be operated in two different modes - soft
Knee or hard Knee. Soft knee mode offers a gentle compression curve around the
threshold point, and is traditionally employed to yield a more subtle, musical type of
compression effect. The hard knee setting causes the full compression ratio to be
applied immediately the signal has passed the threshold point, so tends to produce
more pronounced and severe compression.
Gain Make Up.
While the subjective sound quality of the signal can be improved by compression, the
overall signal level will be reduced when gain reduction is taking place. The Gain
Make Up control is designed to boost the compressed signal by between 0 and 20dB,
in order to bring back the level to the same loudness as the uncompressed signal.
Without this control, comparing the original and compressed signals becomes
difficult, since there would be a level drop each time the compressor is switched in:
therefore it is normal to adjust the Gain Make Up control so that when the ‘compressor
on’ switch is activated, the audio signal remains constant in level.
Unlike the Output Level control, the Gain Make Up control is active only when the
‘compressor on’ switch is engaged. Once the Gain Make Up has been adjusted, use the
Output Level control to set the overall output level of the Ebony A3.
Compressor On.
This switch enables or disables the compressor stage, thus allowing an A/B
comparison to be made between the original untreated signal and the compressed
signal. Any gain make up applied to the signal only becomes active when the
“Compressor On” is enabled. An associated status LED indicates when the
compressor is active. The Gain Reduction on the VU meter will monitor the level of
compression regardless of the compressor stage being active or non active.
Equalisation.
The Ebony A3 equalizer section has three bands, each with a continuously variable cut
and boost control up to plus/minus 15dB. The mid band has a rotary knob to select the
centre frequency and is variable between 150Hz and 7KHz. Remember that there is a
good deal of gain available from the EQ section, and greatly boosting one or more
bands can cause the red Peak LED to illuminate as the Ebony A3 is driven towards
clipping. In this case you need to compensate by bringing down the Ebony A3 output
gain control until the Peak LED is extinguished.