FDMP203 – Computer Applications 2 Task1: Report Word Count: 1,090

Current Synthesis and Sampling Platforms

Types of synthesis and principles of operation:

Additive Synthesis

Gordon Reid (2000), explains that Additive synthesis is based on sounds made by combining a series of sine waves at different frequencies by adding harmonics to the fundamental frequency. A good example is the Vintage B3 Organ plug-in on Logic pro x, by controlling the routing of air through various pipes; you can create a variety of timbres leading to a complex waveform. Below are diagrams showing the fundamental of a sine wave and the harmonics produced from the fundamental. Although any waveforms can be used, Sin Waves are most commonly used, as they are the only pure waveforms without harmonics. By adding sine waves of varying frequency and amplitude, more complex tones are created.

Subtractive Synthesis

Roland (2016) state that the tones in Subtractive synthesisers are created by subtracting unwanted frequencies, to form the sound that you’re looking to produce. The main components to any subtractive synthesiser are the Oscillator, Filter, Amp and LFO. An Oscillator generates a repeating signal in a particular waveform. Oscillators output the full sound of a waveform, containing all of its dynamic range and harmonic frequencies. The main four types of oscillators are Sine, Sawtooth, Square and Triangle.

When filtering a sound, a VCF (Voltage Controlled Filter) is used to remove unwanted frequencies from the original sound. The most common filters used are a Low Pass Filter and a High Pass Filter. Low pass filters allow low frequencies to pass through cutting out high frequencies and leaving bass. A High Pass Filter does the opposite. Turning the cutoff knob on a synthesiser shifts the point at which the filter starts to act on the sound.

The amplifier on a subtractive synthesiser, also know as a VCA (Voltage controlled Amplifier), controls the volume of the sound. Most VCA’s contain a volume envelope, which breaks down into four parts, Attack, Decay, Sustain and Release (ADSR).

An LFO is an oscillator used to manipulate all tones. LFO’s have a rate control that changes the speeds at which it oscillates and depth controls. LFO, which stands for Low Frequency Oscillator, can produce signals having a frequency as low as 0.02Hz. The upper frequency limit frequency limit for many LFO’s is around 20Hz. You can select only one destination for the LFO or you can switch on serval destinations at once.

Examples are the ES2 and Retro Synth in Logic Pro X.

Frequency Modulation Synthesis (FM)

Philip Mantione (2017) reveals that FM Synthesis was one of the first digital synthesis methods and is based on the use of two oscillators; a Carrier and a Modulator. A carrier is related to the fundamental frequency (sine, saw, square and triangle) and is controllable with a MIDI input, for example a keyboard. A modulator is used to alter the sound of the carrier at a specific modulation rate or intensity. An FM synth can have many operators to shape a sound resulting in a complex waveform. A good example where this technique is used is in Depeche Mode’s People Are People.

An example is the EFM1 in Logic pro X.

Wavetable Synthesis

Music production nerds (2018), states that Wavetable synthesis is a type of synthesis where the sound constructed are modelled on the single-cycle waveform of a sound source. The sound source can be a natural sound, like a voice, or a sound from another synthesiser.

Reverb (2018), explains that in a Wavetable there are 4 oscillator waveforms, Sin, Triangle, Saw and Square acting like layers. With a Wavetable synthesiser you can switch between the waveforms. By turning the LFO’s on the wavetable position, you can manipulate how much it is modulating across the table. This allows you to focus in on a segment of the wavetable or the full wavetable.

The advantages of Wavetable synthesis is that the technique can reproduce sound of musical instruments better then other modulation synthesis, such as FM. Wavetable makes use of less memory, waves at full resolution can be stored.

Examples of Wavetable synthesis are Serum and Massive.

Granular Synthesis

White Noises (2018), states that granular synthesis is the process of slicing or dividing an audio signal into separate audio clips called “grains”. When slicing the audio fades are used to prevent clicks and pops, the shapes of these fades are called an envelope. Envelopes are applied to grains to smoothen out the sound or used to increase the volume of the sound. The advantages of granular synthesis are that you are able to stretch the timing of the sound to enable a slow motion or a reserved sound; you can also change the pitch of the grains to a higher or lower pitch. Grains are less than 50ms in duration and typically in the range of 10-30ms.

Combinational synthesis (Alchemy)

A Combinational synthesiser is a hybrid synthesiser which offers an Additive, Subtractive, Spectral, Granular and Sampler elements. An example of this is the Alchemy plugin in Logic Pro X.

Apple (2017), states that Alchemy can be used to analyse imported samples and manipulate the samples using one or more synthesis methods. An Alchemy preset can contain up to four sources. You can morph or crossfades between sources, which can be used by adding digital filters and effect units.

What is Sampling and Sampling Systems

Kevin Cornell (2016), explains that Sampling is the process of reusing an original portion of an artist’s recording, this could be drum combinations, guitar rifts to a verse or chorus of a vocal. To use a sample in your own work, you need permission from two license agreements, the sound recording (administered by a record label) and the musical composition (administered by a publishing company). Unlicensed use of sampling can lead to potential liability for copyright infringement.

Sampling is an on-going debate within the industry with artists arguing that sampling is not helping musicians to learn the fundamentals of music composition and programming. Other artists say that sampling is on the rise and helps the creativity of musicians and promotion of the artist if it is a well-known song. Without the use of sampling, Electronic and Hip-Hop music would not be on the rise.

Philip Mantione (2018), explains that samplers in synthesisers act in a similar way, by uploading a sample into a synthesiser and using a MIDI keyboard to trigger a single note sound. These are called zones. A zone is a location where a single sample is loaded. A sample can be outlined across a range of notes on a keyboard. A root key is assigned with each sample, when played the sample will playback at the same pitch and speed from the original recording. Playing other keys in a zone will speed up or slow down the sample resulting in a pitch change. However, most samplers allow you to keep the pitch and speed setting independent for a specific zone if you have a rhythmic component that is synced to a tempo.

There is an envelope sections to control the amplitude attack, decay, sustain and release (ADSR). These can be linked to other controls such as a low-pass filter.

Bibliography

Apple. (2019). Logic Pro X: Alchemy overview. Available: https://support.apple.com/kb/PH27371?locale=en_US&viewlocale=en_US. Last accessed 21st Jan 2019.

Gordon Reid. (2000). An Introduction Gordon Reid. (2000). An Introduction To Additive Synthesis. Available: https://www.soundonsound.com/techniques/introduction-additive-synthesis. Last accessed 28th Nov 2018.

Kevin Cornell. (2016). Music Sampling: Breaking Down The Basics.Available: https://www.tunecore.com/blog/2016/08/music-sampling-breaking-down-the-basics.html. Last accessed 21st Jan 2019.

Reverb. (2018). Wavetable Synthesis Explained. Available: https://www.youtube.com/watch?v=_w1h4vknfow. Last accessed 21st Jan 2019.

Roland. (2016). A BEGINNER’S GUIDE TO SUBTRACTIVE SYNTHESIS.Available: http://www.roland.co.uk/blog/guide-to-subtractive-synthesis/. Last accessed 28th Nov 2018.

Philip Mantione. (2018). The Fundamentals of Sampling Instruments & Libraries. Available: https://theproaudiofiles.com/fundamentals-sampling-and-instruments-libraries/. Last accessed 21st Jan 2019.

Philip Mantione. (2017). Introduction to FM Synthesis. Available: https://theproaudiofiles.com/fm-synthesis/. Last accessed 28th Nov 2018.

Music Production Nerds. (2018). What is Wavetable Synthesis? – Wavetable Synthesis Explained. Available: https://musicproductionnerds.com/what-is-wavetable-synthesis. Last accessed 28th Nov 2018.

White Noises. (2018). Granular Synthesis EXPLAINED. Available: https://www.youtube.com/watch?v=ftDLRYnRYZQ. Last accessed 21st Jan 2019.