LinPlug Spectral - Manual (Page 71)

Reverb
The Reverb effect is used to add ambiance to sounds.
The Predelay dial enables you to delay the processed signal by a given
amount (in milliseconds) so as to achieve a more natural reverberation.
Normally, shorter Predelay times are applied in the case of smaller room
sizes while longer Predelay times are applied in the case of larger room
sizes. Range: 0 ms...125 ms.
The time display also functions as a Sync popup menu can be used to sync
the Predelay time with the current tempo (see Appendix A for the range of
possible sync settings).
The Roomsize dial is used to set the size of the simulated room. The
Roomsize varies from a small chamber up to a huge hall.
The simulated room's wall materials can be adjusted with the Damp
(Damping) dial. This parameter ranges from practically loss-free reflecting
walls (0% damping) up to very absorbent walls (90% damping). In practical
terms, the amount of damping determines the amount of higher frequencies
that are contained in the processed signal: The higher the Damp (Damping)
setting, the more that higher frequencies are removed from the processed
signal.
The Reverb also allows a decent modulation which is controlled with the
Mod Depth dial; the effect is similar to a chorus and suppresses a certain
metallic sound which might appea in large rooms. However, using
Modulation also has a decent Damping effect on the signal, so naturally
with Modulation higher frequencies are decaying faster than lower ones, so
as you increase Modulation you may need to adjust the Damp parameter.
The Mod Active switch allows quick comparison of the signal with and
without modulation.