IMPORTANT: This project is very old and no longer mantained. Code is open source and you can find it on Google Code. You can also find a ZIP package here. I don't plan to support this VST or to mantain the code anymore.
4 Band Shifter is a VST Plugin that is able to scale (shift) independently the pitch of 4 adjacent, user-definable frequency bands. Pitch-shifting algorithm is based on Stephan M. Bernsee's article, Pitch Shifting Using Fourier Transform.
Plugin uses FFTW library to perform fast STFTs.
Short overview about the graphic components and knobs:
I. Pitch knobs
Each one of them controls the amount of pitch shift of the correspondent frequencyband. Pitch shifting range goes from -12 semitones, or an octave down, to +12 semitones, or an octave up. On the LCD, brighter band colors represent a positive shift in pitch, darker colors a negative one. Behaviour of pitch knobs is affected by the state of the discrete mode button (see below)
II. Volume knobs
Simple volume multipliers for each one of the bands. A value of 0 mutes the corresponding band, a value of 1 makes it sound full-volume, any value between the two lowers band amplitude proportionally. On the LCD, the height of a band represents its volume.
III. LCD Display
It gives graphic information about the plugin parameters: each band is represented by a rectangle. Width represents the frequency extension, height represents amplitude multiplier (set by the volume knobs) and band color represents the amount of positive (brighter) or negative (darker) pitch - shifting
IV. Band Endpoint knobs
These 4 knobs set the end point of the correspondent band: First band starts always at 0 Hz, and ends at band 1 knob value in Hz. Accordingly, band 2 starts at band 1 knob value, and ends at band 2 knob value etc. Upper bound for band end points is 20Khz.
V. Discrete/Continuous switch
When this button is turned on (bright red LED color), pitch shifting behaves "discretely", that is you can shift up or down the pitch only by multiples of one semitone in the range ±12.
Download and Install Info
You can download the ZIP package here; it's not yet provided with an installer, so you've got to copy bernspitch.dll in your VTS Plugins folder, and fftw3.dll (FFTW library) in your windows\system32 folder.
This plugin is open source. You can find the project page on Google Code here.
For any question, feel free to mail me @ email@example.com