Vocoders & talkboxes
The most classic robot vocal effects are typically either a vocoder or a talkbox. But what’s the difference between the two?
Vocoders and talkboxes are easily confused, not least of all because they sound incredibly similar. Because of their sonic similarities, you can arguably substitute one for the other, which, as we will discover, may not be such a bad idea – if you want to hang on to your teeth!
Carrying vocoders
Contrary to many people’s assumptions, the vocoder itself is not actually a synthesiser, although it is quite usual to find a synthesis element within a vocoder, especially in plugin form. The vocoder component joins together two elements, both of which are required to make the classic sound. Firstly, we need a carrier wave, which is most commonly some form of synthesiser or inbuilt synth circuit. In the software realm, this is usually included as part of the plugin, and can be controlled by either setting a specific note or single chord, or using a keyboard to play notes in order to follow the chord progression of a song.
The second component that is required is a modulating signal. For a classic robot voice, this would need to be some kind of vocal, although it is not uncommon to use other instruments, particularly ones that are percussive in nature. Artists as diverse as Stevie Wonder and Röyksopp have been known to send drums in the direction of a vocoder, while playing chords that follow the song.
Smart plugins
If we consider original vocoding hardware for a moment, some of the best vocoders produced, shipped in the form of a box with no synthesiser attached. The Sennheiser VSM-201, EMS 2000 and Roland SVC-350 are all fine examples, but all requiring an external synthesiser, as well as a microphone input.
Roland realised that it could place this technology in a keyboard, and include a carrier circuit, in the shape of string and choir sounds. Hence the SVC-350 was somewhat better known as the infamous Roland VP-330, which Roland still produces today, but now in the guise of their boutique-shaped VP-03.
If this classic Roland sound is the sort of vocoder that interests you, then help is at hand in the software domain, too. Softube hasbeautifully engineered a reincarnation of the VP-330, as a software plugin. Moreover, it has a built-in carrier wave generator, so you won’t need to fiddle around with a separate synthesiser in order to get your vocoder to work.
Got a mic?
All software vocoders will allow recorded audio tracks to be routed toward the plugin. This means that if you have a lead vocal already, you could employ this as your modulating signal. Playing chords alongside this vocal will provide the effect of beautiful electrified backing vocals.
Vocoders can, however, be a little fussy about the modulating input. As we have already mentioned, percussive sounds work very well, so it won’t come as a surprise to learn that the more percussive and articulated a vocal sound, the better the vocoded effect will be. For this reason, die-hard vocodists tend to prefer a vocal input via a dynamic microphone. There are plenty to choose from, with classic choices being the Shure SM57/58, Shure SM7B or the Sennheiser MD-421, which is well known in the recording industry as a perfect mic for recording toms on a drum kit. Therefore, you might find it better to record a separate vocal track, specifically for the purpose of using with your vocoder plugin.
Squashed and compressed
Like the vast majority of recorded vocals, compression can play a major role, whether deployed at the input or the output stage. Vocoder circuits will behave better if they have a steady and reliable compressed signal for the purposes of modulation. Whether you are vocoding vocals, drums, or anything else, compress your signal, as your vocoder will thank you by providing better results.
Talking of boxes…
Vocoders can often be confused with a different technology, called a talkbox. Unlike vocoders, the talkbox can only exist in the hardware domain, although there are plugins available that try to mimic the characteristic sound.
Talkboxes operate in a very simplistic way, but can be difficult to use. As they were originally designed as guitar pedals, you will find many talkbox examples available as guitar stompboxes. In essence, a signal from either a guitar or synthesiser is fed into the effects pedal, before it becomes amplified, to a relatively loud volume. The signal then heads to a speaker, which is enclosed, except for the attachment of a plastic tube, where the sound is literally funnelled. The user then puts the tube in their mouth, before mouthing lyrics or vowels, back into a microphone for the purposes of either live performance or recording.
Think of the opening riff to Bon Jovi’s Livin’ on a Prayer and you will recognise a fine guitarbased example. This is also incredibly popular in the synthesiser domain, on classics such as the opening of Bruno Mars’s 24K and many
Daft Punk tunes.
The only problem is, as the sound is so heavily amplified, all those high-volume frequencies swirling around your mouth can cause problems for your teeth! Don’t believe us? Ask Peter Frampton, who became well known for using the talkbox with his guitar, and has been a denture wearer for many years!
Because of their sonic similarities, you can arguably substitute one for the other…