Before you buy yourself or friend a harmonica, be sure to read the following to learn the differences between the different types and categories of harmonicas. Aside from the standard diatonic and chromatic harmonicas, most other types are for special purposes or special effects and not as commonly used. Most professionals primarily play diatonic or chromatic harmonica.


  • DIATONIC HARMONICAS:
    The standard 10-hole major diatonic harmonicas come in all 12 keys of music and allow you to play a complete 7-note major scale of the key of the harmonica. Many additional notes from outside the major scale can be acquired by "bending" certain draw (inhale) and blow (exhale) notes. Most professional players are predominantly diatonic players. Diatonic harmonicas are typically used in blues, rock, country, and folk, but are found in nearly all styles of music.
    Harmonicas- diatonic
    They are sometimes referred to as a "blues harp", "harp", "short harp", or "standard 10-hole". The particular model and brand of diatonic played by your favorite pro is not important when choosing a harmonica, more importantly, learn to play like the pro and you will sound like them. If you are at all serious about learning to play, start with a good quality one. The cheaper ones leak air, are very difficult to learn to bend, and can cause no end of frustration.


  • CHROMATIC HARMONICAS:
    The chromatic harmonica has a button on the side, which when NOT pressed in, allows you to play a normal major scale in the key of the chromatic. With the button depressed, you have all the missing half-step notes in-between the major scale notes. This allows you to play in any key and any type of scale.
    Harmonicas- Chromatic
    The chromatic is typically used in jazz and classical music, but is found in all styles of music. Bending doesn't work nearly as well on the chromatic as it does on the diatonic harmonica and when used, is used more for a "bending effect". In most cases, you will be doing good to bend a note a half-step down.


  • TREMOLO HARMONICAS:
    Tremolo harmonicas are Diatonic models constructed with double holes (sometimes 8, 10, 12, or more sets of double holes), each containing two reeds tuned to the same note, one tuned slightly higher than the other. Since both reeds are either blow or draw, when played, both will sound together and the slight difference in tuning creates a vibrating or tremolo effect.
    Harmonicas- Chromatic
    The tremolo harmonicas are primarily used for special effects. They are not made to play blues, bend notes, or do anything other than play the most simple melodies. Depending upon the particular model and brand, the major scale would begin on the 3rd or 4th set of holes, and then the pattern would be the same as the diatonic major scale pattern in relation to blows and draws.


  • OCTAVE-TUNED HARMONICAS:
    Octave harmonicas are similar to Tremolo models in reed layout and musical range. Instead of having reeds tuned to the same note, however, each double hole has one reed tuned an octave apart from the other.
    Harmonicas- Chromatic
    The resulting sound is stronger and full bodied, but without the tremolo effect. This is the harmonica equivalent of a twelve-string guitar (sort-of).


  • ALTERED TUNED DIATONICS:
    For players that do not play chromatic harmonica, but may have the need for additional notes and scales in their playing, they can pick up an altered (or special) tuned (actually re-tuned from the standard major scale tuning) diatonic.
    Harmonicas- Chromatic
    Tunings include: natural minor scale, harmonic minor scale, major scale 2nd position tuned (Lee Oskar calls them "Melody Makers" and Hohner calls them "Country tuned"), and "high octave" (key of "G") and "low octave" (low D, Eb, E, F, and F#) tuned.


  • OTHER TYPES:
    Additional types of harmonicas are available for special purposes like harmonica trios, groups, or orchestrals. Most of these are made by the Hohner Company, but other companies such as Seydel and Suzuki carry some as well.
    Harmonicas- Chromatic
    This group includes: bass harmonicas, chord harmonicas, Polyphonias, and miniture 4-hole harmonicas.