How Does A Harmonica Work?

The harmonica has been used by many popular artists over the years, notably, Bob Dylan, Neil Young, Springsteen...

It’s most often associated with the blues due to its penetrating, solemn sound, but it’s a pretty diverse instrument, used across all genres, from rock and pop to jazz, country, or even classical music. 

At its most basic description, the harmonica works in a similar way to a pipe organ or accordion. The player selects notes by placing their mouth over the holes, rather than pressing keys as you do on a keyboard. 

The air flows past a metal reed - usually made of brass or bronze - and this causes a vibration, and subsequently, the sound we know and love - the harmonica. 

How Does A Harmonica Work

How The Harmonica Works 

When the player blows into the harmonica, air enters through the “comb” of the instrument, which contains the air chambers that cover the reeds.

In modern harmonicas, the comb is often made of plastic or metal as these materials offer more durability, but on traditional instruments, it was made of wood.

Inside the harmonica, the sound is generated by groups of reeds mounted on reed plates. As we mentioned before, reeds are usually made of brass or bronze, but you’ll also find harmonicas with steel, aluminum, and plastic reeds. 

The reeds located inside the comb’s air chamber respond when blown into, while those on the outside respond to inhaling. The length of the reeds influences the pitch of the notes, with the longest, lowest reeds situated to the left.

The reed-plates are situated in a part of the harmonica known as the cover plate. The tonal quality of the instrument can be determined by the material of the cover plate, which can be made from metal, wood, or plastic.

Types of Harmonica 

There are different types of harmonica. The most common are diatonic, chromatic, tremolo, and octave. Each type plays a different range of notes and is best suited to a certain type of music. 

For example, the diatonic harmonica is a popular choice for blues and country music. Most of these contain 10 holes; the four middle holes comprise an octave, while holes on either side extend the scale. 

The chromatic harmonica usually has 10, 12, or 16 holes, and also has a button-controlled slider that allows the instrument to play all 12 notes of the chromatic scale. This harmonica is mainly used for jazz and classical music.

In contrast, tremolo harmonicas are diatonic models with double holes. They have two reeds tuned to the same note, one slightly higher, which creates a tremolo (or vibrating) effect. This makes it a popular choice for gospel, Latin, Asian, and international folk styles of music. 

Similarly, Octave harmonicas also have double holes but differ as the reeds are tuned one octave apart. These harmonicas are popular in Cajun, old-time, and Irish music.

Playing Techniques 

Playing the harmonica looks simple, but it’s a lot more technical than it looks, as it’s not a matter of simply blowing into some holes.

When starting out learning the harmonica, beginners often find it difficult to develop their mouth technique, however, once they pass this phase, they can learn tricks and techniques that change the pitch.

For beginners, there are two main methods.

The Pucker method requires you to start with your lips relaxed. You’ll notice that if you exhale or inhale, you will hear multiple notes. Push your lips outward, in a kissing motion, and experiment until you can get a single, clear note.

Some people find it useful to think of their lips as being over or around the harmonica, rather than just on it. Bear in mind that if you look ridiculous when you take the harmonica away from your lips, then you’re probably doing it right! 

There’s also the Tongue method where you relax your mouth so it is covering multiple holes, then cover the ones you don't want with your tongue.

This technique is often used to "split" notes, allowing you to play two notes that aren't directly next to each other by putting your tongue in between them. It’s a little tricky to get the hang of, but can be a useful method for building your playing technique. 

Advanced Techniques 

‘Bending notes’ on the harmonica involves changing the shape of the mouth to produce sharps and flats.

It’s notoriously difficult for beginners and requires players to relax and coordinate muscles in the throat, mouth, and lips. The term is borrowed from guitarists, who literally "bend" a string to create pitch changes. 

Bending allows a player to reach all the notes on the chromatic scale, and also creates the glissando characteristic of much blues harp and country harmonica playing. While bending on the guitar bends the pitch upward, typically "bending" on the harmonica causes the pitch to fall downward. 

‘Overblowing’ or ‘Overbending’ works in a similar way, only with additional air forced out while blowing. In the 1970s, Howard Levy developed the "overbending" technique which inspired players like Chris Michalek, Carlos del Junco, Otavio Castro, and George Brooks to play the entire chromatic scale. 

When overbending, the lower of the two reeds in a chamber vibrate faster, while the higher-pitched reed vibrates slower which enables the player to isolate the higher of the two reeds and play higher notes. Players also use a technique called cross-harping, which plays the harmonica in all 12 keys by utilizing bending techniques.

Brands of Harmonica

There are numerous harmonica brands out there, but the most common are Hohner, Hering, Lee Oskar, Suzuki, Seydel, Bushman, and Huang.

Hohner is one of the most popular, and Lee Oskar harmonicas are good for beginners, as they are very easy to play and create a great sound.

In Conclusion 

The harmonica is an iconic instrument loved for its nostalgic, wholesome sound that is utilized by a range of genres and artists.

Different types of harmonicas offer distinctive sounds, with some best suited to blues or rock, and others used for country, jazz, or classical music. 

However, the harmonica is certainly not as simple as it seems, and to play a range of notes, you need to develop and broaden different mouth techniques.