What is Aftertouch On A Keyboard?

what is aftertouch on a synth

What is Aftertouch on a synth?

The expressiveness of the keyboard is its way of reciprocating to a certain change from its normal functions. A keyboard is capable of using melodious sound by itself but with the addition of a synthesizer it can create music which is out of the box. The variations and twists incorporated to model the expressions produced by the keyboard is a remarkable leap in the music industry. The changes can be of three types:

Sensitivity to velocity: – Changes made to how fast the keys of the keyboard are struck.

Sensitivity to pressure: – Also known as Aftertouch, depicts the pressure exerted on the keys to create modulations.

Sensitivity to displacement: – To what depth the keys are pressed in order to create variations.

Clavichords and some professional keyboards are Aftertouch sensitive whereas acoustic pianos are velocity sensitive and pipe organs are displacement sensitive. Aftertouch on Synthesizer keyboards, composed of keys, are difficult when it comes to portraying expressiveness but some professional and new aged keyboards have this quality of Aftertouch which sets them apart from others.

What is Aftertouch?

Aftertouch in a way is a sensation which can be noticed once the key is depressed. It is basically triggered once a key is struck and then the associated filter is applied to it. Volume, vibrato, tone, pitch and other expressions can be controlled with the help of Aftertouch feature in synthesizers.Intonations can also be adjusted with the help of Aftertouch. This pressure sensing feature on the synthesizer has the versatility to change and customize music according to the needs of the player. By making modifications and deciding the amount of pressure required, voice modulations can be performed. With a customizable interface and editable format, Aftertouch has changed the face of recording and creating music.

Types of Aftertouch

Aftertouch produces MIDI control signals and the output depends upon the intensity with which the key is struck.

There are two types in which Aftertouch can be divided:

Channel Aftertouch: In this no special treatment is given to particular keys on a keyboard. The same amount of pressure is distributed throughout or to a subset of keys. It is the most common type of Aftertouch and produces a MIDI signal when the keys are pressed.

Polyphonic Aftertouch: This is a much more sophisticated and customizable form of Aftertouch. Each key has its own sensor which creates a different expression for keys when pressed down. The sensors involved identify if the key is pressed or not.

What is Aftertouch On A Midi Keyboard Synthesizer 

The CS80– was the first synthesizer, introduced in the 70’s, facilitated with the Aftertouch feature. This synthesizer by Yamaha was so powerful in its own way that it could create an unbeatable experience. Featuring the polyphonic Aftertouch, CS-80 could apply filter on a single key even if multiple keys were pressed down. This vintage synthesizer could easily go for a prize of 10,000$ even today.

The Yamaha GX-1– keyboard creates a side to side motion in order to create the Aftertouch effect. This motion can be used to invoke vibrato. Aftertouch keyboards have a thin strip underneath it imparting the variations to the tones depending on which keys are struck and how.

The Yamaha EX-5- is a highly sophisticated and customizable synthesizer with the best features available. With the availability of pressure sensitivity it enables the player to pick and choose the effect that suits the music the best. Another unbelievable feature of this synthesizer is its versatility; it can replicate many non keyboard instruments like an electric guitar. By changing the pitch with the Aftertouch feature the player can create an illusion of a heavy metal guitar.

Applications of Aftertouch

Creating swells in music:  By assigning Aftertouch to a lowpass filter, you can make the sound much bolder. A swell basically is a gradual increase and a sudden decrease in the sound. This can be achieved by cleverly using the Aftertouch and pressing the keys harder and softer as required.

Using Vibrato:  A common and most used feature of Aftertouch is vibrato. It creates a depth in the music by changing the pitch of the voice. There are two aspects to vibrato, the amount of variation in pitch and the speed with which the variation is carried out.

Percussion effects: The beauty of Aftertouch is that with the help of it you can change a keyboard into any possible instrument. It may be violin, guitar or even drums, the possibilities are immense. All this can be possible by retouching the pitch and hitting the keys hard to get the maximum effect out of it.

Control signal processing: Few synthesizers do full justice when it comes to a signal processing feature. By controlling the MIDI signals one can customize echoes, harmonies and even random effects.

Guitar imitation: Pressing the keys of the keyboard can create the same effect of sticking the chords of a guitar by using Aftertouch. A good control over the pitch and correct sensitivity applied will create a harmonious guitar like sound just like the way you wanted it to be.

Problems faced with Aftertouch

No doubt that Aftertouch feature of a synthesizer has many applications but some things are still missing and problematic. Different synthesizers have different features and the Aftertouch is not capable of controlling all the parameters of sound. Pitch bend and velocity are common features for all synthesizers but rest of them vary. The interface is not very user friendly and difficult to grasp. This has to be updated for the players to have a better experience. The ease with which the Aftertouch works can vary from model to model. There are some problems issued with the smoothness with which the keys can be pressed. Another important issue is the portability of the patch of music from one synthesizer to another as the abilities and features of Aftertouch vary from one another. It is better to use common effects so that the patches can work on any synthesizer.

Who is Robert Arthur “Bob” Moog


The legendary inovative Robert Authur “Bob” Moog, is a united states pioneer of electronic music, he is widely known as being the creator of the Moog synthesizer.

Formative Years

Robert Arthur Moog, was delivered on May 23, 1934 in Queens, New York City, he turned out to be very clever and was always creating. His mother provided him with piano keyboard classes early, however his particular pastimes ended up much more like his father’s, in electrical engineering. When he was Fourteen, youthful Bob Moog constructed a theremin, an electronic device which was created in the 1920s by means of a European developer named Leon Theremin. Theremins worked with an electro-magnetic field to help generate a unique noise. Participants would move their own hands in close proximity to a wire loop to alter a specific sound.

Just before Bob finished at the Bronx, NYC High school of Science in the early 1950’s, he established the actual Moog Enterprise, with the assistance of his dad, and they would together sell theremin packages simply by teleshopping and word of mouth. Moog earned enough revenue which then allowed him to attend a Queens College, then in 1957 graduating with a Bachelor degree of Science. He eventually received his masters diploma in electro-mechanical engineering via the University of Colombia as well as a Ph. D in engineering science coming from Cornell University in 1965, Bob Moog was a really hard worker and had a plan from the start.

Innovative Businessman

Following college, Bob Moog obtained employment in corporate study plus continued manufacturing theremins. In the early 1960’s, he published a write-up on a electronics magazine, and as a result acquired 4,000 more purchases for theremins in a very short period of time, which would end up being manufactured in a three-room residence. Because of this achievement, Moog attained his Ph. D in engineering physics.

Making use of the cash from his theremin product sales, Moog developed as well as designed other electronic sound instruments, which consists of an analog synthesizer, an enormous enhancement coming from the original instrument, a bedroom type of synth was created in 1955 by way of the RCA Enterprise, which in turn ended up selling for thousands of dollars. Moog’s synthesizer ended up being built with a keyboard and therefore was put into use by using patch cords to create various pitches. Through the years, Bob upgraded the musical instrument together with polyphonic as well as stereophonic sound, enabling musicians to experience numerous melodic noises plus unique effects.

The Music Industry Embraces the Moog

Multipurpose and low-cost, Bob Moog’s musical instruments came into common use amongst many rock and roll musicians throughout the mid-1960s, most notable the Beach Boys and various other legends. In 1968, the groundbreaking traditional album called Switched-On Bach was published, showcasing electronic variations of Bach classics. This recording album would go on to sell an incredible number of copies and therefore delivered global acknowledgment to Moog’s synths. Bob’s corp was at a all time high and ending up being the go-to device for many musicians around the world, In the early 1970’s, Bob designed the scaled-down, more compacted MiniMoog, which had been ideal for live events. It evolved into a most desired instrument for bands such as pink floyd and Tangerine Dream. Because of its flexibility, the MiniMoog had also been highlighted in Stevie Wonder’s committed 1973 R&B hit “Living for the City” wow, what a time.

Difficulty along with Revival

While in the 1970s, a lesser amount of pricey electronic digital synthesizers bombarded the industry. Moog was lacking the financial knowledge to steer his organization throughout competing periods. By 1973, Bob Moog wound up selling all the legal rights to his corporation. In 1978, he relocated to North Carolina, and established the big Briar Music corporation, constructing theremins along with analog synths. Meanwhile, Moog synthesizers experienced an upsurge of recognition within the 1980s and futher on due to the fact that quite a few music artists desired their warmer noise over the more affordable synth companys. Through the 2000’s, Bob had effectively fought against the Moog name in court and altered the naming of Big Briar Music to Moog Music.

Last Years

Robert Authur Moog turned out to be diagnosed with brain cancer in 2005, and then would later die on August 21, 2005 at his residence in North Carolina. The actual Bob Moog Foundation was developed as being a commemorative, for the exact purpose of moving forward with his life’s work on building synthesizer music. R.I.P Bob Authur Moog a legend also a inspiration to any synth enthusiast.

Check Out This Bob Moog Documentary