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Bitspeek LPC Vocoder

Sonic Charge

  • • Real-time linear prediction codec (LPC) effect

Audio examples

Bitspeek is a pitch-excited linear prediction codec effect. It takes audio input, breaks it down into synthesizer parameters and reproduces the sound using an oscillator, noise and a formant filter.

Despite having only a few simple controls, this box can produce a broad range of sounds from cheap speaking toys to high-end vocoder and talkbox effects.

Bitspeek was created by Magnus Lidström, the man behind Malström.

Product details

Bitspeek is a real-time pitch-excited linear prediction codec effect. Right now you are probably thinking, "oh, another one of those"? Or perhaps not. Chances are that you have never heard about "linear prediction", although most of us use it daily when we talk on our cell phones. Linear prediction coding is a voice compression technology that appeared in commercial products in the seventies and was implemented in some well-known speaking toys of the early eighties.

We have used this technology to create an audio effect that analyzes audio, extracts a number of parameters (including pitch, volume and formant data) and then resynthesizes the audio using an oscillator, noise and a formant filter. A number of playback parameters can adjust the pitch and tonal quality of the sound. It is possible to play the pitch with MIDI notes and you can create tempo-synchronized "formant freezing effects".

In addition to the AU / VST version of Bitspeek, the Rack Extension version also offers:

  • External audio input allows you to use the formant filter on any material.
  • Lots of CV ins and outs for integrating into your rack and scoring high on geekness factor.

Bitspeek ships with a selection of Combinator patches that demonstrates the possibilities with the extra inputs and outputs.

Download full Bitspeek RE User Guide here:  Bitspeek RE User Guide



Released: 2012-10-04
Version: 1.0.1