These notes will help you get the most out of Flip Speed, the rectification-based octaver with an attitude problem. DirectX and VST versions are available.
Flip Speed generates octaves by two methods: flipping the polarity of the incoming
signal at cycle boundaries, and playing the signal back at either half or double speed.
It works best on monophonic sources - leads, basslines, melodies, even vocals. If you use it on tracks with
no clearly-defined pitch (such as mixes, chords or drums), you will get unpredictable results and distortion -
nasty... or interesting.
Even with perfectly monophonic sounds it is not an exact science - you will probably not get pure octave tones
(at least, not from the wave flipper channel), so it is not a transposition effect.
Controls
The Octave switch lets you choose between an octave below the input signal, and an octave above.
The Flip channel will be generating sub-harmonics and harmonics rather than transposing the input.
For the octave down, every alternate cycle is flipped, generating a sub-harmonic one octave below the input.
For the octave up, the entire signal is rectified - the portion of the waveform below zero is flipped above zero,
generating an octave harmonic.
The Speed channel on the other hand will be playing back the wave cycles at half or double speed, skipping or
repeating cycles to "keep pace" with the original.
The Pre Filter knob controls a simple low-pass filter to remove some of the higher harmonics
before the rectification is performed. This can reduce glitching and make the generated octaves clearer,
but of course you are losing some of the clarity of the original signal.
The Speed channel operates on the unfiltered original signal, since it is more robust.
The Blend knob controls the mix of Flip and Speed channels.
The Distortion knob drives the rectified signal into a smooth clipping algorithm, giving an edge to the sound.
The Post Filter knob controls a low-pass filter after the octave generation performed.
Rectification generates quite a lot of high-frequency harmonics and artifacts in addition to the octaves.
The Post Filter can smooth these out a little if you like.
Also, since the Speed channel did not operate on a filtered waveform, you may want to filter out some of the
double- or half-speed harmonics.