Weiss Enginering Ltd.
DAC501-4ch/DAC502-4ch
To give you the possibility to reduce such displeasing sounds of too high sharpness we developed the auto-
matic Weiss De-Esser. Moreover you are able to choose between two different De-Esser modes and how
much of the overall sharpness should be kept. So with the Weiss De-Esser you are able to create your
individual desired sound regarding the sharpness of the playback.
The characteristic of sharpness of a S also explains the origin of the name De-Esser - whose purpose is
limiting S sounds or in general limiting sounds with sharpness. Below you can see a block diagram of the
algorithm of the Weiss De-Esser. There are four main parts of the algorithm which will be introduced in the
following.
Figure 30: Block diagramm of the Weiss De-Esser plugin
Sounds with high sharpness are concentrated in the mid-signal of the audio information. So the Weiss De-
Esser only processes the mid-signal and lets the side-signal untouched.
This idea is based on the so called m/s-stereophony. Which is a coding process that transforms the signals
of the left and right into a different representation. The mid-signal is the sum of the left and right channel.
As opposed to this is the side-signal the difference of them. For realizing this idea a m/s-encoding and
decoding is integrated at the beginning and the ending of the De-Esser chain.
Figure 31: Comparing different settings of the De-Esser user parameter: a) original; b) Amount -12 dB.
The second block performs a sound distinctive analysis. This block enables the De-Esser to recognize cer-
tain transformations of the signals frequency content which are important for limiting high sharpness. The
measurements of this analysis are super fast like in the section of the Weiss dynamics adoption described.
But still the overall picture is captured to factor the slow changing behaviour of the audio into the evaluation.
This is warranted by implementing a capacity of remembering into this block.
The knowledge generated by the second block is then used in the third block. Here the decision whether
User Manual and
33
White Papers
