Contrary to the effects I covered in “Part 1” of this lesson, in “Part 2” I will deal with modulation effects that alter sounds in ways that one might call dramatic and bizarre.
Although these – more or less – “advanced” effects have been on the market for years, they are increasingly evident in contemporary music genres.
Here are four exotic modulation effects that producers find very valuable.
A ring modulator is a popular tool that affects both frequency and amplitude. It mixes two waveforms, thus adding frequencies to the output that are the sum and difference of the frequencies present in each signal. These “sum and difference tones” are often more prominent than the original signals. It is also unlikely that they will be harmonically related (since addition/subtraction is linear and pitch is perceived non-linearly). The result is a rich, unique texture – quite inharmonic and clangorous (like metallic bells).
Out of the parameters in a ring modulator, the most significant is the “frequency” of the waveform. It mixes with the carrier. In most cases, it is accompanied by dry/wet and phase parameters as well as additional oscillators.
A resonator, generally, is a unit that affects tone by emphasizing particular frequencies. They take an incoming audio signal and run it through a series of filtered delay lines. When these delay lines are mixed with the original dry signal, it multiplies the amplitudes of certain frequencies again and again. In addition to this, resonators allow you to create a sustained tone out of non-sustained sounds. You can even achieve “vocoder-like” sounds by tuning the parameters just right.
Resochords is one example of a late and more advanced resonator unit. Furthermore, Resochords features more parameters and options for customization. Moreover, it allows several comb filters to be implemented and individually tuned to produce a selected chord (see blog: Diatonic Chords). The results are most interesting on percussive content (like drums) because they force Resochords to generate “new” harmonic content spontaneously.
The vocoder is, shall we say, one of the most disruptive inventions to hit the music production industry. It has strongly influenced contemporary music. You can easily recognize it by its distinctive robotic, “talk-box” sound.
A vocoder is an audio processor that alternates the human voice. Producers most commonly implement it as a real-time A-D-A converter/processor; inputting a human voice, disassembling its qualities, and turning them into a stream of modifiable digits. You can also use some vocoders as an insert effect, like a “resonant” EQ. In this implementation, the vocoder imposes the characteristic peaks and noise components in speech sounds called “formants” onto the input via filtering.
Granular synthesis is a technique that rapidly sequences small bits of sound (called grains) over time. It is excellent for creating soundscapes and other ethereal music. Typically, each grain is between 20 and 100 milliseconds, but they can be longer/shorter. Shorter grains are often perceived as clicks. This can be a desired sonic effect for experimental sounds.”Intergrain time” is the silence between grains. You can also customize it. Also, each grain has its own parameters for control such as envelope shape, length, pitch, and amplitude. Grains can be performed mono-phonically or poly-phonically, with or without delay, with a programmed or a random sequence. Imagine the intricate, astonishing sounds you can uncover with this tool.
PRACTICAL USE & AUDIO EXAMPLES
Ring modulator – popular today as an insert effect in samplers and DAWs, used by producers on countless sources from guitar to synths.
Perhaps the best example of this application would be on a short synth sequence. Consequently, I automated the frequency & LFO speed parameters for some extra movement.
Pad Clean with Ring Modulation
Resonator (ResoChord) – You can apply it to a variety of sound sources to add tasteful harmonics (mentioned earlier) and/or build a chord out if one note.
So, in this example, I processed a vocal recording with a resonator.
Vox with Resonator
Vocoder – widely known as the “robotic voice” effect. With this in mind, I think I should try it on a vocal recording.
Vox with Vocoder
Granulator or granular synthesis – also exemplified effectively on vocals. So, by time stretching, pitch shifting, and manipulating the recording on a granular level, you will experience radical psychedelic change.
Vox with Granulator