GSnap is an auto-tune effect. It can be used
subtly to correct the pitch of a vocal, or, with more extreme settings, to
create a robot-voice effect.For GSnap to work effectively, the input signal
should be monophonic, at a good level and reasonably noise-free. For example, a
clean, mono vocal recording, without excessive noise or reverb. Effect plug-ins
should be placed after GSnap in the signal chain.
GSnap starts off by detecting the pitch of the incoming audio.
The Min Freq and Max Freq parameters help the pitch-detector by narrowing the
range of frequencies it needs to consider. Also, the Gate parameter should be
set so that the pitch-detector ignores background noise during "silent" passages.
The Speed parameter sets the number of wave repetitions
required for positive pitch-detection. Lower values for Speed will allow faster
pitch-detection, but will increase the chance of false detection. The default
value should be fine in most cases.Once a pitch has been determined, GSnap
applies the specified pitch-correction. There are two modes of pitch correction:
fixed scale and MIDI. Fixed scale correction has a fixed set of snap-notes,
while MIDI correction is controlled in real time by MIDI data.
The Threshold parameter sets the largest pitch-shift that
will be applied to the input. It defines a region around each snap-note that
will be corrected to that note. The GUI shows the snap-notes and regions in
effect at any time.The pitch-detection and correction can be made to use a
different reference frequency using the Calibrate parameter. This sets the
frequency of A above middle C.
Additionally, GSnap will respond to pitch-bend and modulation
MIDI messages to apply pitch-bend and vibrato. The Pitch Bend, Vibrato and Vib
Speed parameters control these effects.