Kill Dry is a feature that has become increasingly popular on delay-based effects and is a feature that we added to our Immerse Reverberator. We are often asked how Kill Dry is different than a 100% wet setting, how one might use it, and what happens when the effect is bypassed.
Quite simply, Kill Dry is intended to be enabled only when the pedal is placed in a parallel effects loop. Similarly, Kill Dry should be enabled if the pedal is used with the aux or effects send of a mixer (which is also a type of parallel effects loop).
Some effects — especially, delay-based effects — are added back with the "dry" (unaffected input) signal to create the output signal. Kill Dry does exactly what the name suggests: it completely removes the dry signal, even when the effect is bypassed. This is exactly what you want in a parallel effects loop, because your primary signal path already contains the dry signal.
Effects that are capable of 100% wet signal via a Mix knob operate differently, because they are intended to be used in a series effects loop or series effects chain. When the pedal is bypassed, the dry signal is restored.
So, what's the difference between parallel and series (normal) effects loops?
- A parallel loop creates a parallel signal path, which becomes the send for effects loop. The return from the loop is added back to the dry signal path. Some prefer this type of loop, because there is no uncertainty about how the dry signal may be affected by the outboard effects. However, this type of loop is problematic when using multiple effects. Since the reason for this is somewhat complicated, I will save this discussion for another blog post.
- A series loop simply inserts the effects in series with the dry signal. Whether the effects are connected in a dedicated effects loop or before the input to an amplifier, this is still a series signal chain. This is the most common type of signal path and is the type we prefer.
Generally, parallel loops are labelled as such, whereas series loops are simply labelled as "effects" or "FX" loops.
So, there you have it: Kill Dry is for parallel effects loops. To achieve a 100% wet signal with a series signal chain, choose a pedal that can achieve 100% wet signal via the Mix knob.