LinPlug relectro - Manual (Page 13)

The filters operate with infinite slope, this means, that every wave-cycle
which represents a frequency outside the selected filter range is drastically
cut away. Its not lowered in volume or anything, it just vanishes completely.
To find out what happens with the resulting gaps (after all when you
completely remove certain cycles you have gaps in the audio stream), see
next chapter.
There is a comprehensive section in relectro that deals with pitch and
frequencies. Top-left it starts with a mode switch. The description of the
modes is much longer than the practical relevance of it, anyway, its working
like this:
-
In GAP mode every gap that arises (in example from the cut filter just
described, but also due to raising pitch) simply remains a gap. This is
good fro some raspy sound (well, it can create many flavours of
sound, but this half way describes it in one word).
- In FILL mode, whenever a gap arises, its filled with the just played
wave-cycle. So a certain cycle may be repeated once or multiple time,
if followed by a gap.
- In BLEND mode finally, the position and size of the gap is considered
and its filled with a blend of the previous and the next wave-cycle so
that you get a more continuous transition (or blending) of the
waveforms.
In practice Gap sounds clearly different from Fill and Blend while the latter
two are quite similar. Appendix A shows some graphics to illustrate the
three operation modes.
LinPlug relectro user manual Page 13