Introduction – Sonic Charge Bitspeek RE User Manual

Page 3

Introduction

I N T R O D U C T I O N

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 applied 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 a simple oscillator, noise and filter

architecture.

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". 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.