Apr 27, 20232 min read

U-Blocking on Harmonica | What, Why and How to U-Block Single Notes | Beginner Harmonica Lesson

U-blocking is a technique used to play single notes on a harmonica. It is done by curling the tongue to block off the holes on either side of the hole you want to play. This allows you to isolate the note you want to play and prevents other notes from being played. In this harmonica lesson I'll teach you how to U-block quickly and effectively.

How to U-block

To U-block, place your harmonica in your mouth and curl your tongue so that it blocks off the holes on either side of the hole you want to play. Your tongue should be in a U-shape.

Only 50% of the population have the genetic code which allows them to do this with their tongue. If you can't do it, don't worry - you can use another embouchure such as lip pursing or tongue blocking.

CAN'T DO IT?: Try lip pursing or tongue blocking

Check out my lesson 3 Ways to Play Single Notes

What does U-blocking look like?

Your curved tongue should look like this:

Curved tongue for U-blocking harmonica embouchure

When you put the harmonica to your mouth, it will look like this:

Man playing harmonica with U-block mouthshape.

Notice that the lips look relaxed rather than tense. Try breathing gently, blowing and drawing air through the harmonica while keeping your tongue in place. You should be able to play a single note without any other notes being played.

Practice U-blocking with each hole on the harmonica. Once you are comfortable with U-blocking, you can start to use it to play songs.

Practice tips for U-blocking

Here are some tips for U-blocking:

Stand in front of a mirror to check your U shape before playing.
Keep your tongue still while breathing through the harmonica.
Try every hole on the harmonica. Each location will feel slightly different.
Be patient. It may take some time to learn how to U-block!

Why should you U-block?

When you first breathe through the instrument, you'll get several notes playing at once. So you need to learn to isolate single notes so you can play melodies. There are several ways to do that, and U-blocking is one of them.

U-blocking isn't the most common approach but it can be useful for some beginners. You need a relatively narrow mouth but you'll also be using your tongue, so it's a great option if other mouthshapes haven't worked for you.

In a way, U-blocking is a sort of combination of lip pursing and tongue blocking. You need to narrow your mouth - but not quite as thin as with lip pursing - and then use your curved tongue to give you the accuracy of a single hole. U-blocking is popular with some folk harmonicists as they can move quickly between holes to play accurate triplets and other fast runs.

I hope you enjoyed this lesson. Let me know in the comments!