Playing the subtones (flats and sharps) on a recorder can be more difficult than playing whole notes. Remember, one note’s flat is another note’s sharp, so, mastering sharps means you are also mastering flats. While there are a few tips on how to produce the correct tones, the most important advice for mastering these important shades of sound is to practice them, paying special care to work on making the transition to those tones from the other notes in the piece of music you are learning to play.
Master the Basics
Place the top of the recorder between your lips, without touching it to your teeth. Gently hold the instrument with your left thumb on (or near) the hole in the back. Your right hand will take care of the notes on the bottom half of the recorder.
Blow gently, but consistently, through the hole, with your left thumb completely covering the hole in the back, and your left index finger completely covering the top whole on the front. As you blow, pretend to speak the word "too." Your tongue is controlling the flow of the air through the instrument. The "t" helps your tongue form a precise start and stop to the note. This is called "tonguing."
Practice playing the note above, which is a "B." If you hear a sound that is more like a squeak, check to make sure you are completely covering the holes. Also, remember to blow gently and mouth "too."
Learn the fingering of each individual note by using the fingering chart that came with your recorder, or, use the interactive chart included in the resources section. Be sure to check that you are using a C chart for a recorder in C (Soprano/Descant, Tenor and Great Bass Recorders) and an F chart for F recorders (Sopranino, Treble, Bass and Contrabass).
Learn the fingering for the subtones by consulting your fingering guide. You'll notice that many of these tones are made by only partially closing the hole in the back. This can be a tricky slide of your thumb, since by opening the hole either too much or not enough produces the wrong tone. Practice a comfortable method of sliding or shifting your thumb off of the hole, listening to the tone change.
Practice transitioning to a subtone from a variety of notes. In any given song, you may need to transition to a specific sharp or flat from any number of different notes. Repeated practice will help you get a good feel for exactly where the correct position of your thumb needs to be to hit the correct note.
Listen to yourself as you play. Listen for sour notes and trouble spots as you practice. These spots are the places you'll want to spend extra time practicing to smoothly play the phrase at the correct tempo.
If you are having trouble knowing whether you are hitting the correct sharp with your recorder, get the sheet music to a song whose tune you know well and that has a number of sharps in it. When you know the song well, you'll know what the tone should sound like when you play it. If it sounds wrong, keep practicing getting exactly the correct fingering.
When you change to another recorder, you may find that the fingering you've mastered is slightly different, especially if the recorders are made of different materials. You may need to get a fresh "feel" for these subtones on the new instrument.