Vocoders: practice and assortment
Vocoder (English voice coder – voice encoder) – a speech synthesis device based on an arbitrary signal with a rich spectrum. Initially, vocoders were developed in order to save the frequency resources of the radio link of a communication system for transmitting voice messages. Savings are achieved due to the fact that instead of the actual speech signal only the values of its certain parameters are transmitted, which on the receiving side control the speech synthesizer. The speech synthesizer is based on three elements: a tone generator for forming vowels, a noise generator for forming consonants, and a system of formant filters to recreate the individual characteristics of the voice. After all the transformations, the human voice becomes like the voice of a robot, which is quite tolerable for communications and interesting for the music industry.
Vocoder as an unusual effect was adopted by electronic musicians and subsequently became a full-fledged effect thanks to manufacturers of musical equipment, which gave it the form and convenience of a musical effect. Vocoder as a musical effect allows you to transfer the properties of one (modulating) signal to another signal, which is called the carrier. A human voice is used as a modulator signal, and a signal generated by a musical synthesizer or other musical instrument is used as a carrier. Thus, the effect of a “talking” or “singing” musical instrument is achieved. In addition to the voice, the modulating signal can also be a guitar, keyboards, drums, and generally any sound of a synthetic and “live” origin. There are also no restrictions on the carrier signal. By experimenting with a modeling and carrier signal, you can get completely different effects – a talking guitar, drums with a piano sound, a guitar sounding like a xylophone.
Modern vocoders can be divided into hardware (with which it all began) and virtual (appeared much later with the development of computer technology for creating music). In practice, a computer musician uses virtual vocoders much more often, implemented as VST-plugins (VST-pugins), since they are more flexible in tuning. Applied similar solutions vocoders are not by themselves, but in conjunction with the host program. As such, any virtual studio that supports VST technology can be used, for example, Cakewalk SONAR, Steinberg Cubase or Fruity Loops Studio. The host program allows you to connect the actual vocoder itself, and choose where the carrier and modulating signal will come from (some vocoders have a built-in carrier synthesizer) – from synthesizers and samplers (which, by the way, also have the VST format), or from microphones and others connected to the sound tool map. And the carrier signal is controlled by MIDI commands coming from a MIDI sequencer or MIDI keyboard to a VST plugin (synthesizer or sampler). An example of virtual vocoders is VST plugins such as Steinberg Vocoder, Fruity Vocoder, Akai DC Vocoder, Voctopus, AC vocoder, Formulator, Lpc-vocoder, Darkoder, Cylonix (as working independently (standalone). Anyone familiar with its principle device can assemble its own vocoder in any modular program such as NI Reactor / Generator, Max MSP, Buzz Composer. An example of hardware vocoder can serve Electronics EM-26 with integrated syn Tesator, Korg KAOSS PAD 3 (digital), Korg VC-10 Vocoder, Boss Vt1-Vocoder, Sennheiser Vocoder, Korg R3 Synth & Vocoder, KORG MicroKORG SYNTHESIZER & VOCODER, MAM VF11 Vocoder, Analog Lab Vocoder X32 Rol Plus, EMS Vocoder.
So, in short, a regular abstract vocoder is a device with two inputs and one output. Two signals are input:
Carrier – a signal that sets the fundamental tone or harmonic component of the output signal, the so-called “Carrier”
Modulator – a speech signal that requires processing (or a signal modulating the “carrier”).
Let’s look at a specific example of how a vocoder works, which is built into the well-known sequencer FL Studio. This is a very good, classic vocoder, it has an input for both the carrier and the modulating signal.
Create a new project and add two tracks to it. One of them will be our processed vocal part (modulator), and the second will be the track that sets the “melody” (carrier)
Next, add Fruity Vocoder to the free channel of the mixer (let it be FX1). We send both of our tracks to the same channel.
What are vocoders (Vocoders: practice and assortment)
And now we do the following: we move the carrier pan control to the right and the modulator pan control to the left (a forced trick by Fruity Vocoder’a, because the effect has only one stereo input, therefore, the left channel will deliver the carrier inside the vocoder, and the right channel will deliver the voice):