The world of musical instruments is a large and storied one.
Throughout history, humans have created many different types of musical instruments utilizing various forms of sound generation to express ourselves in the language of music.
With so many different build types and materials, it may be overwhelming to pick out the differences between them.
We’re here to help make this easier by listing the major categories all instruments fall into. Let’s dig in!
The Traditional Groups Of Musical Instruments
String. Instruments where the primary source of sounds is generated by vibrating strings.
Wind. Instruments where the sound is generated by resonating air in tubular enclosures. This can be further categorized into woodwinds and brass.
Percussion. Instruments that create percussive sounds and are generally associated with rhythm and sounds made from striking pitched and unpitched media.
Keyboard. Instruments that utilize a keyboard to interact with any number of sound generation media.
While these broad categorizations may seem straightforward, the truth is there are some distinctions that may surprise you.
For example, while being an instrument made of brass, a saxophone is considered a woodwind instrument, and pianos can actually fit into three categories at once.
You might ask, “How so?”. It’s time for a closer look.
The “rock star” of recognizable instrument types is as good as any to start.
String instruments (also known as chordophones) immediately conjure up images of wailing electric guitars or large grandiose symphonies, and with good reason.
Not only are they considered one of the most popular types of instruments to play, but they are also instantly recognizable by their use of the categorical namesake, strings.
There’s no shortage of examples here. Guitar, violin, viola, cello, bass, banjo, sitar, ukulele, mandolin, harp, etc. The list goes on and on.
String instruments generate their sound by harnessing the vibrations of strands in a fiber medium. I’d place a bet that we’ve all made simple string instruments in our lifetimes.
Taking a rubber band or string and stretching it between the fingers is all but instinctual. Next thing you know you’re plucking away while stretching the band to make slight pitch changes.
This is the essence of string instruments. Varying lengths and thickness (gauge) of string combined with tension to harness the vibrations of the strings into sound.
String instruments also generally have some sort of resonating chamber to amplify and enrich the sound.
Here the strings connect with the hollow body of the instrument further resonating the sound.
For example, acoustic guitars, with their hollow bodies can play much louder and have more body and tone than a solid body electric guitar with no amplifier.
Electric string instruments like the aforementioned electric guitar, use powered sensors known as pickups.
Pickups are sort of like electromagnetic sensors that are very sensitive to the material of the string instrument. They will take the vibrations of the strings and convert them into an electrical signal which is then amplified in an amplifier to generate the sound.
String instruments can be plucked, strummed, bowed, or even hammered. The magic is in harnessing the frequencies developed by vibrating the strings.
Here, even the material of the string, and its thickness, can completely alter its sound and or use.
Violin strings (and other related orchestral string instruments) were famously made of animal intestinal lining for many years for their sound quality.
Not that I would endorse such practice in the modern world, but rather point to the rich history of exploring various mediums for their tonal quality.
Wind instruments are most commonly recognized for the use of air generated by the mouth to resonate in specialized tubes made of various lengths and materials like metal or wood.
Here, humans have made very clever ways of accessing the various pitches that can be generated with the varying lengths of resonant tubing.
The use of slides, valves, and keys allows the musician to access many different pitches quickly to play melodies. They are essentially shortening and elongating the resonant space to create pitches.
There’s no shortage of well-known examples to draw from. Commonly seen wind instruments are flutes, trumpets, saxophones, tubas, clarinets, and basically any horn-like instrument from various cultures and time periods.
Wind instruments are also commonly subdivided further into woodwinds and brass.
Woodwind instruments generate their sound by having the musician blow air over a sharp edge to split the air, or over thin pieces of wood that vibrate against a surface.
Instruments like a flute use the first method. The musician will very skillfully blow air over the mouthpiece of the flute to “cut” the air.
This is then further modified when in the resonant tubing of the flute. Here, not only does the flutist’s breath create the sound, but the use of the valves on the flute further alters the pitch.
The latter method refers to the use of reeds. Reed instruments have thin pieces of wood that either vibrate on a surface like a clarinet or a saxophone, or against another reed like an oboe.
Despite the name, woodwind instruments can be made of anything, not just wood.
The flute and saxophone are great examples of this. Both are made of metal, but the method of sound generation falls under the category of woodwinds.
Brass wind instruments generate their sound by capturing the resonance generated by the musicians vibrating lips.
Brass instruments also use slides, valves, and keys to adjust the tube length to create pitches.
As with all wind instruments, the sound is based on the character of the materials used and the length and size of resonant tubing.
For example, trumpets are short relative to a tuba, which accounts for the trumpet’s higher note capabilities, vs. the tuba’s specialty in the lower frequencies.
Bread and butter examples of brass instruments are trumpet, trombone, tuba, french horn, etc. Similar to woodwinds, brass instruments are not limited to the materials of the namesake.
A digeridoo is considered to be part of the brass instrument family despite being entirely constructed of wood. It’s the action of using the vibration of the lips to generate the sound that puts it in this category.
Wind instruments have been a huge part of human history.
They’ve been used because of their versatility, but also because they can create sounds with a lot of volumes that can be heard at distance.
One thinks of the singular bugle player that wakes up the entire base with the iconic US army wake-up call.
The ability to create a sound that is much louder with the use of tubes is a precursor to amplification technology in general.
So whether it’s in a large orchestra or a lone trumpet solemnly playing taps, wind instruments have a broad family of sounds that have been with us for a very long time.
The percussion family of instruments finds their categorization through the use of instruments that make a sound when it is struck, shaken, or scraped.
Creating rhythms based on timed strikes on percussive instruments is probably as old as humanity itself.
One can hardly think of a more simple way of expressing yourself musically and capturing rhythm.
Clapping hands to music is probably the first lesson anyone inadvertently learns and processes as a toddler in relation to musicality and our interaction with it.
Here our hands are the percussive instrument. Give a toddler a little drum and they’ll quickly arrive at striking it with any number of items creating that connection between themselves and the sounds it can produce.
Percussion instruments are one of the more broad categories of the four we mention.
As I had noted before the piano can be considered a percussive instrument but at the same time a string and keyboard instrument. Similarly, there are some wind instruments that can be considered to be percussive like a slide whistle, or the udu.
It’s the nature of the playing that can make a percussive instrument from almost anything. If you’re striking, shaking, or scraping something it’s technically a percussive instrument.
The use of keys in musical instruments has almost become the symbol of music itself in many ways.
We’ve come to visually associate the classic black and white keyboard of a piano or organ with music in general. Even the word itself “key” board, sort of speaks to this.
They are access points to tonality. Keyboards might be described as a series of levers designed to play music with the fingers.
These levers can be used to activate any number of media such as strings in the case of a piano, or wind in the case of a pipe organ.
Keyboard instruments are admittedly a bit odd categorically as the methods of sound generation could apply across the types I had just mentioned.
In the case of a piano, you might categorize it as a stringed percussion instrument with a keyboard, which is absolutely legitimate.
Still, keyboard instruments have a very unique place in the music world, and I feel it’s correct in the application as its own category.
Commonly known keyboard instruments would be the piano, organ, harpsichord, accordion, and synthesizers. Lesser-known instruments are the hurdy-gurdy, celesta, and melodica.
The first known and documented instrument with a keyboard is the hydraulis.
These were documented in the 3rd century BC, and like all early keyboards were an organ. Later iterations of keyboard instruments began the use of strings like in the clavichord or harpsichord.
Here the keys mechanically pluck the strings in either instrument. The next major development would be with the piano.
The piano was unique in that not only did it use hammers to activate the strings, but it also allowed the player to play louder or softer depending on their style of play.
This allowed for a much more dynamic range of sounds compared to the harpsichord, which initially was far more popular.
Today you can find keyboards in an electric format as either an electric piano or even as a synthesizer. Synthesizers use electrical signals and filters to emulate the sounds of just about anything.
All sounds have a sort of sonic fingerprint, and by matching this as close as possible you can very much recreate certain timbres.
So whenever you hear a synthesizer play a sound that is similar to a piano or string sound, this is because it has been made to manipulate the pure audio signal to mimic this audio “fingerprint”.
Keyboard instruments allow for a degree of control and range that many instruments simply cannot. They allow our nimble fingers to do the work of many hands. (Imagine hitting the strings of a piano manually with hammers by hand.)
For that reason, they remain one of the most powerful and popular formats for instruments.
The history of music and our various interactions with the physical world to create musical instruments is a long and fascinating road.
The four major types we outline here in this article are what we would consider the canonical groups of musical instruments, but that’s not to say there aren’t grey areas or other schools of thought on the matter.
The combination of expanding technology and sound production methods is only growing with the world of electronic instruments. Who knows where we might end up?
Maybe there will be an entirely new set of categories to draw from in the future. Either way, hopefully, you now have a quick introduction to the major types of musical instruments today.