Equaliser Frequency Responses

The Dead Duck Equaliser and the EQ module of the Dead Duck Channel provide 4 bands of equalisation with up to 12 dB of boost or cut. In addition, the actual frequency curve of each band can be modified using the Q parameter which is available on all bands except the Channel HF band.

The following plots show the frequency-response curves for the low frequency (LF) and low-mid frequency (LMF) bands with varying amounts of gain and Q. In all cases the plots show the responses at the default frequencies for the band.

Gain

The LF shelf band features the following frequency response, from -12 to +12 dB with no Q applied:


and the LMF band:


Note how the boost/cut shape is asymmetric with a broader boost curve and a more focused cut response.

Q

The LF shelf band features the following frequency response, at +12 dB with Q applied in 20% steps from 0 to 100%:


and at -12 dB:


Note how the boost response dips below 0 dB and the cut response rises above it as the Q is increased.

The LMF band at -12 dB and +12 dB over the same Q range:


Conclusion

The plots shown here are typical of the shelf and bell curves provided by all the bands in the EQ plugins. The bands not illustrated here show similar responses within their respective frequency ranges, except for the high-frequency (HF) band shelf response which is a mirror image of the LF shelf curve.