Speculum Free Comb Filter

Speculum Free is a modulation tool capable of operating as a comb filter or as a standard delay effect. The only difference between the two operating modes is in the scaling of the Delay Time parameter. Its range is between 0s and 0.02s while in Comb Filter mode, whereas the maximum value is increased to two seconds while in Delay mode. Obviously, the developer’s idea was to allow for more precise adjustments when using the plugin as a comb filter, as even the smallest of delay time shifts will result in a different sounding timbre.

The plugin also features a built-in low-pass filter with cutoff and resonance controls. The filter is placed outside of the feedback path, so it only affects the signal before it reaches the delay stage. In other words, the feedback signal is not affected by the filter. As a result, the effect is easier to control when working with longer feedback times (to prevent resonance buildups and excess volume) but also somewhat limited as a creative sound design tool. That said, Speculum Free can cover a range of effects, from basic delay and comb filtering to flanging, phasing, and more.

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