User Guide

Waves IR-1 software guide page 23
DIRECT SIGNAL
Please Note: The Direct signal is not the dry signal! The dry signal is the input signal to the
plugin.
The Direct signal is the direct arrival of the sound source to the listener, traveling the shortest
straight-line path between them. The Direct signal is the signal that was directly emitted from
the speaker and recorded by the microphone. It is the input signal convolved with the first
reflection in the IR. The direct signal differs from the Dry signal (that is, the unprocessed
input to the IR-1) since it includes the effects of air damping in the original room and the
transfer function of speakers and microphones used. For purist simulation of the sampled
acoustics, you should turn the Direct On, and set the Wet control to fully wet.
Since most of the time you will be using it as a reverb, the default setting of the IR- series
has the Direct signal Off. The idea is that in a reverb, it is more likely to use the Dry signal
rather than the Direct, especially when working in send mode. The Direct is not the Reverb
and therefore it is Off by default.
Note that IRs that are sampled from Reverb devices at 100% wet do not have a direct
signal. The IR-series is programmed to auto detect if a direct signal is available or not. If the
imported IR has no direct signal, then the direct signal On/Off control will be disabled.
In some cases, when importing an IR that doesn’t have a direct signal, the IR-1 may mistake
the first Early Reflection as a direct signal. In this event, the direct On/Off will be enabled
and should be turned On. Otherwise, you may loose the first Early Reflection of your IR.
If you reduce the “Direct Gain” to “Off”, it will only attenuate that parameter of the IR.
However, if you switch the Direct to “Off” by using its “On/Off” button, the Direct will be
completely cut from the beginning of the IR and the whole IR will be shortened and re-
aligned so that the wet signal is aligned with the latency (the IR will start with the true direct
arrival time). This enables the user to delete any unnatural pre-delay caused by the pre-roll
of the impulse response.
EARLY REFLECTIONS
The early reflections start at the first reflection after the Direct, and extend several tens of
milliseconds. They maintain their discrete echo sound. The IR-1 separates them by analysis
of the IR and you can still move the ER/Tail separation point using the ER/TR- X control.
Early reflections are mostly responsible for a natural-sounding room and the perception of
localization and distance.