A vocoder was primarily designed to make long-distance communication easy, with the reduction of signal bandwidth. The process of coding/decoding was costly, initially. Even the speech clarity was not up to the mark. An adequate vocoder was updated in the year of 1942 for the U.S. military purposes. It encrypts the control signals sent from the envelopes and protects transmissions against interception. Know what is it and how does it work reading this article.
How to Use a Vocoder
What is a Vocoder?
The word ‘Vocoder’ is made from the combination of ‘Voice’ and ‘Coder.’ It is an audio processor that helps in transmitting speech or voice signals in the form of digital data. If there is a need for digital coding, then a ‘voice encoder,’ i.e., a vocoder, comes into the picture. It works best for speech and voice simulation. Knowing about its work, it looks like it is quite a new invention. But surprisingly, it was developed in the late 1920s by a physicist Homer Dudley.
Journey Between The Military to Music
Electronic music was experimental during the years of the early 19s. After many years of research and experiments, it became popular in early 1970. At that time, it was popular to provide an ideal environment for distorted voice effects. Because of that, the majority of the people loved that and accepted it with open arms! Then, a well-known composer Wendy Carlos and the best synthesizer of that era Robert Moog built a musical vocoder.
Dudley’s design inspired this vocoder in 1970. It was astonishing at that time to run a speech pattern through a musical keyboard, literally allowing it to “talk” in a robotic voice. The makers did it just by assigning the carrier signal to a synthesizer and the modulator signal to a microphone input. It was indeed a revolution with the simplest change.
The German electronic group Kraftwerk was the first group that used such sounds in their vocals. Their music mainly focused on computers and technology, and that’s why they could use the robotic-sounding vocoder vocals well. This way, the musical vocoders came into the filed of music from the military. After that many other groups used robotic-sounding vocals either by using vocoder or by a talkbox.
How a Vocoder Works
Generally, vocoders are typically used to create robotic voices. But apart from that, a vocoder can also be used to generate a wide variety of effects. It operates on the principle of formants – a speech made by the human voice. Vocoding uses frequencies of one sound and then translates it to the other – mostly in a robotic sound.
This process mainly requires two sound sources – a modulator and a carrier. The first one works with an evident rhythmic character, and the other one is like a rich synthesizer sound. For a better understanding, you can say that the modulator source is for vocals or drums, and the carrier is for a string or pad.
The modulator signal runs via continuous bandpass filters that break the message into different ranges of frequency. After that, a level analysis meter analyzes the signal level of each band. The carrier signal runs via bandpass filters. Here, the level of each filter is linked to one of the previously mentioned analysis meters. If you use more bandpass filters, it will cause your carrier signal to sound more like the modulator signal.
If you want to use a vocoder like a professional, then it is mandatory to know some other parameters and controls. Each Vocoder is different, and you need some additional features. Not every Vocoder includes them all, though.
- Band Numbers – They are meant to be the total number of filter bands starting from the 4 to 6 groups for the vintage sound and gradually offer more detail.
- Frequency – It is straightforward to set an upper and lower rate for the vocoder bands. These frequencies can be divided between the number of groups available.
- Envelope Setting – The envelope settings decide the promptness of response effects and the dynamic changes in volume.
- HF Emph or Unvoiced – It is a high-pass filter that helps in improving intelligibility for the unvoiced elements such as the letter t, d, b, etc.
- Formant Shift – It is mainly for techniques that apply to the vocoder filter bands and shift the ranges up or down across the frequency spectrum.
How to Set Up a Vocoder
Step 1: Creating an Audio track for Modulator Signal (Vocals)
Step 2: Creating a MIDI track for Carrier Signal (Synth)
Step 3: Adding Vocoder to the track with Vocals
Step 4: Choosing a Sidechain Input Source after the ‘External’ Carrier Type
Step 5: Adjusting the Vocoder settings such as a number of bands, envelopes, and other controls.
Step 6:Taking care about Dry/Wet controls for balancing the processed and dry signals.
So this was the basics/introduction of Vocoder and its relations with music. The more you will play with it, the more ideas you will generate and learn. It’s trending in modern popular music, and many musicians and singers love to create their tracks with the Vocoder. If you are a beginner, you can take inspiration from ‘The Middle’ and ‘Pony.’ I hope this article works for you. Stay tuned for more updates. 🙂