Digital Audio Amplified Synthesizers vs. Pianos: An Audio Producer’s Guide By Jennifer Martin | September 4, 2020 Should you learn how to use a synthesizer to become an audio producer? What is the difference between a synthesizer and piano? Synthesizers and pianos are two vital components of the music industry. Because of their expressional versatility, these instruments are staples in everything from concerts to recording sessions. Thus, it is paramount for an audio producer to know the functions of each and how they can be used for the desired result. What is a Synthesizer? A synthesizer is an electronic instrument that is typically played by a keyboard. It is known for its ability to produce many different sounds, even emulate other instruments, making it a versatile and valuable tool for audio producers. Synthesizers generate and combine audio signals, manipulating sound-alteration techniques such as additive synthesis (adding together sine waves to create timbre), subtractive synthesis (filtering an audio signal to alter timbre), and frequency modulation synthesis (altering the frequency of sound waves to create harmonic and inharmonic sounds). With its wide range of capabilities, the synthesizer is essential to nearly all sectors of the music industry. Components of a Synthesizer Regardless of the interface, synthesizers utilize the oscillator, LFO, envelope, filter, arpeggiator, and controller. Each component has its own purpose and can change the sound of the synthesizer in many different ways. Mastering the components of the synthesizer is important to making music as an audio producer. Oscillator The oscillator is the generator of the synthesizer, analogous in function to the strings and bow of a violin or cello. Analog synthesizers use Voltage Controlled Oscillators, which convert direct current signals from the power source into alternating current signals. This causes the resulting signals to oscillate, generating specific frequencies that produce sound. Digital synthesizers employ digital signal processing, a numerically controlled mechanism represented by binary numbers (0 and 1) that generates a specific waveform. While analog oscillators are expressed with geometric line diagrams, digital oscillators are represented by sine waves on a numbered graph. Analog synthesizers are still used today, but digital synthesizers are the more sophisticated technology since they have greater control over the quality and precision of the sound produced. LFO Low Frequency Oscillator (LFO) modulates sound. It operates below the range of human hearing, below 20Hz, at the bottom of the audio range. It creates a rhythmic pulse to modulate synthesizers and delay lines. Envelope The envelope controls how a sound changes through time. It manipulates elements such as filters (frequencies), amplitude (volume) and pitch. The most widely used envelope model is the ADSR envelope, which stands for attack, decay, sustain and release. This is similar to how pianos produce sound: The pianist strikes the key and may use pedal to sustain the note or release quickly to expedite its decay. Filter Filters are typically used in subtractive synthesis, which attenuates (reduces) an audio signal to eliminate unwanted noise. While analog filters remove signals above or below a specific frequency threshold, digital filters are programmable and thus more precise. Since they operate differently, analog and digital filters cannot be combined; in other words, digital filters can only work with digital signals, and analog filters can only work with analog signals. However, although a tricky and tedious process, it is possible to convert between signals. Arpeggiator The arpeggiator (also referred to as an ‘arp’) is a sophisticated feature that plays the notes of an input chord in an arpeggiated pattern. These notes can be channeled to a MIDI keyboard or sequencer for easier manipulation. The arpeggiator often includes controls for the order, speed and range of the notes, typically with the options of downward, upward or random. Advanced designs can manipulate complex note sequences or play several arpeggios simultaneously. Controller The controller is the interface through which the previously listed features operate. Usually, it is an electronic, digital or MIDI keyboard, which can be built into or joined with the synthesizer unit. Attaching the synth to the controller requires a CV/gate, USB or MIDI cable. Keyboards are a popular option since they provide almost endless expressional capabilities through elements such as velocity and aftertouch. Synth controllers include the following varieties: Ribbon controllers — track a finger’s movement across a surface Motion-sensitive controllers — utilize a sensory technology similar to that of video games Wind controllers — resemble the function of woodwind instruments Touch plates — send signals based on the position and force of a finger Electronic drum pads — analogous to drumheads Microtonal controllers — generate pitches smaller than a semitone (half step) Synthesizer Varieties Synthesizers encompass several different types. The five most common include additive, subtractive, wavetable, FM and modular synths. As an audio producer it is important to become familiar with the many different synthesizer varieties and they may come in handy during different projects. Additive Synth This type is a common choice for pop music. These synthesizers work by stacking sound waves, specifically, sine waves with different frequencies (pitches). This layering process provides a wide variety of different sounds and harmonics. Subtractive Synth Opposite in function to the additive synth, this type starts out with complex tones and harmonics and attenuates specific parts through a filter. This allows for more precision in creating sound, such as bringing out the bass tones or stressing higher registers. Wavetable Synth This type works by representing each note on a wavetable that can be manipulated in a variety of ways, including changes in pitch, timbre or tempo. With this handy synth, you could record a slow melody on the piano in A Major and transform it into a guitar riff in E Minor. FM Synth Popularized in the 1980s, this synthesizer is the epitome of experimental pop music with its inharmonic capabilities. This instrument employs frequency modulation (FM) synthesis, which uses two different types of oscillators: carriers (the audible frequency) and modulators (the frequency that shapes the carrier’s tone). Modular Synth This type is usually hardware, and it consists of different modules (hence the name) that create unique effects. Using patch cables (interconnecting wires), this instrument can transmit audio signals between different parts of the synth. For example, you could run a signal through an ADSR envelope then send it to a module with an arpeggiator or LFO. Components of a Piano The piano is the first true predecessor of the synth. As we have seen already, many of its functions and operations are models for sound synthesis. Invented in 1700 by Bartolomeo Cristofori, who replaced the harpsichord’s plucking apparatus with a hammer, the piano gave rise to unprecedented variety and manipulation in musical expression. The piano is a highly complex and intricate instrument and describing all of its technical elements might take a novel. However, for starters, here are its five basic components: #1: Keyboard This component is a long rectangular board equipped with white and black keys. The standard keyboard contains 88 keys, 36 of which are black (representing sharps or flats) and 52 that are white (naturals). #2: Case This forms the largest part of the piano, including the outer shell that wraps around the body, the legs that support the instrument and the lid that protects the keys. #3: Hammers & Strings Each key generates a unique tone when struck, moving the internal hammer which then strikes a string within the piano’s body. Each string is tuned for a specific pitch. #4: Damper This component lies horizontally across the strings and functions to “dampen” the string’s sound after it is struck, keeping pitches from bleeding together. #5: Pedals Each piano includes three pedals, which are gold or brass-colored appendages located at the base of the instrument and played by the feet. The left pedal, called the ‘una corda’ or soft pedal, shifts the hammers and keys to facilitate a softer attack; the middle pedal, called the ‘sostenuto’ pedal, sustains the notes being held down; and the right pedal, called the ‘damper’ or sustain pedal, lifts the damper to create more reverberation. Synthesizer vs. Piano Synthesizers and pianos share one obvious similarity: In most cases, they both utilize a keyboard. Additionally, many of the ways in which they operate and produce sound are analogous. As we discussed, the ADSR envelope function on a synth mimics how sound is produced and manipulated by a piano. Furthermore, synths often have keyboards with weighted keys to more closely emulate the traditional piano and its expressional capabilities. However, there are also significant differences between these two instruments. Perhaps most obviously, synthesizers can generate their own sound while pianos can only resonate when they are played. Synthesizers also offer editing and recording tools that provide a greater diversity of sound elements and manipulator functions. However, not all synths can be played in real time, and authentic pianos are generally the preferred instrument for performances. Final Thoughts Learning to operate a synthesizer is no easy task, but as with every other instrument, practice makes perfect. Educating yourself on music theory and piano basics is a great place to start. To fully utilize the tools of a synth, however, you will also need to delve into the science of sound design. Ready to learn how to use a synthesizer as an audio producer? Cogswell University of Silicon Valley empowers aspiring audiophiles to master their craft. Our Audio and Music Technology Department’s students are exposed to new ideas and industry-grade equipment and are presented with challenges designed to unlock their creativity. Cogswell University of Silicon Valley is uniquely poised to offer a meaningful and valuable education for 21st century students. We believe in an education that directly correlates with the work you’ll be doing after you graduate. Interested in learning more? Contact Us today.