Harmonica Sound Differences - Wood vs Plastic vs Metal

There is an ongoing debate regarding whether harmonicas produce different sounds depending on the materials used to make them. While some players are adamant there is a distinct contrast in the tonal qualities between wood, plastic and metal, others say the only sound differences are due to factors including: a player’s lipping (how they apply their mouth to the instrument), the shape of the holes, the amount of air pressure applied, use of tongue, length of the reed, type of harmonica being played (which we’ll cover in another blog post) etc. So, who’s right?

Qualities of Wood, Plastic and Metal

    
Originally all harmonicas were made of wood. These instruments are the most popular among blues and marine band players, due to their rich, full-bodied sound. Wood reverberates more than other materials and can be more flexible as the player breathes into it. Wood can swell (due to the heat and moisture of breath flowing through), which can affect the playability and sound of the instrument. This could be one reason players and listeners believe there is a sound difference between materials used to make harmonicas.

Plastic harmonicas have a louder, sharper and more even sound than wood and metal. While injected-molded plastic is the most popular material used to make harmonicas these days, the substance does lack the quality and character of a wooden instrument. In directing a player who is freshly starting out, a plastic comb would be the best due to its cleanability (combs not made of wood can be washed out under the sink, which is helpful), lack of swelling and longer life. 

Metal harmonicas are easier to hold and play, and they tend to have a much longer life than those made with other materials. These instruments create a more powerful, edgier and brighter sound than harmonicas made from wood and plastic. 

The Debate Continues

 
SPAH (the Society for the Preservation and Advancement of the Harmonica) has done listening tests to determine if folks could tell the difference in sound between harmonicas made with different materials. However, the conclusion was not strong enough to make a statement either way. At the end of the day, even if a player can hear the difference in sound, they usually will just stick with the harmonica they prefer.