When you play a chord on the harmonica, you can use your tongue to add texture — sort of like a guitar player does when he plays a fancy strum pattern instead of just hitting the notes of a chord once. You can use several different chord textures, including the chord rake, the chord hammer, the hammered split, and the shimmer.
Take a look at these animated versions of the tongue actions you use to create chord textures on the harmonica.
Alternating tongue placements to produce the chord rake
When you play a chord rake, you rake your tongue from side to side across the holes of the harp while you play a chord. At any given time during the rake, some of the notes will sound, and others will be blocked by your tongue. This constantly changing combination of notes creates a texture sort of like an up-and-down strum on a guitar.
Here’s how you can produce a chord rake:
Start with a chord of three or more holes.
Place your tongue on the harp to one side so that some holes are covered and one or more holes are open.
As you play, slide your tongue from side to side on the harmonica.
Make sure that the edges of your tongue tap against the corners of your mouth to be sure that your tongue is traveling as far as possible to the right and left. Doing so allows you to get the maximum effect from the technique. Here, you can see the left and right extremes of tongue placement when you play a rake.
You can listen to the chord rake applied on the harmonica.
Lifting and replacing your tongue to play a chord hammer
While you’re playing a melody note, you can add an effect called the chord hammer, a rapid-fire series of repeated chords that you play while the melody note continues to sound. A chord hammer sounds impressive (it’s a favorite effect of blues harmonica players), but it’s simple to play.
Start with your tongue covering enough holes to play one note. Then rapidly lift your tongue off the harp and then just as rapidly replace it, continuing to alternate rapidly between the tongue-on and tongue-off placements. When you do this, you get a vigorous undulating sound — your tongue acts like a soft hammer delivering a rapid series of blows.
When you play a chord hammer, you don’t have to move at lightning speed. The effect sounds twice as fast as you’re actually moving, so don’t sweat trying to move your tongue faster than you can control.
A hammered split is just like a chord hammer except for one detail: Instead of starting with a single note, you start with a split. Whenever your tongue is on the harp, holes are open on both sides of your tongue. Then, just like with a chord hammer, you rapidly lift your tongue off the harp and replace it again.
Rapidly alternating widely spaced notes with the shimmer
A shimmer is a little like a chord rake. However, instead of playing all the notes in your mouth, the shimmer alternates between the note on the left side and the note on the right. You can produce a shimmer in one of two ways. You can move the entire tip of your tongue, as you do when you play a rake, or you can keep it in place.
When you do this, you initiate the wagging motion from farther back on your tongue so that the tip of your tongue rocks in place. As it rocks from side to side, it alternately covers the holes on the left and right. Here, you can see the left and right extremes of tongue placement when you play a shimmer.
Playing a shimmer allows you to eliminate chord notes that may not fit with what a guitar or piano player is playing. It also produces a more subtle effect than a chord rake or chord hammer.