Many doublers start out as clarinetists or saxophonists, and many doublers would say that the flute is particularly challenging as a double. These phenomena are related. Let’s look at some of the issues woodwind doublers have with the flute. I’ll offer a sort of glib, inadequate tip or two for each situation, but the real solution here is to learn the flute right, with lots of patience, years of dedicated practice, and a well-qualified and longsuffering flute teacher.
Lightheadedness, inability to play long phrases, fuzzy tone, weak low register. These are products of a too-large aperture (the opening in your lips). Single-reed players tend to have a mental image of a relatively large clarinet or saxophone mouthpiece held in their embouchures. Think instead of the actual opening between the tip of the reed and the tip of the mouthpiece—this is much closer to the size of opening you need to create in your lips. (Think especially of a high-pitched instrument like a clarinet or soprano saxophone, and a mouthpiece with a narrow tip opening.) Or try this: close your lips and relax them as much as possible, then blow gently until a tiny “needle” of air pokes through the center of your lips. That’s how much smaller your aperture needs to be.
Thin/shrill tone, weak low register. The saxophone uses a medium voicing, and the clarinet uses a high voicing, but the flute uses a very low voicing. (Flute doublers coming from a double reed instrument or even a brass instrument have an advantage here.) Keep your airstream very warm, even in the highest register, to give your tone depth.
Uneven intonation and tone. If you are counting on similarities between flute fingerings and clarinet or saxophone fingerings, then you are likely committing a number of flute crimes. F-sharp uses the right third finger, not middle finger. And you must master the ballet between the left index finger and right pinky finger, especially in the transition from first to second octave. (If middle-finger F-sharp and a lazy right pinky sound fine to you, it’s because your tone production technique and tone concept aren’t well developed yet.)
No dynamic control. The typical problem is loud third octave, medium-loud second octave, and very soft first octave. This is a sure sign that you are trying to change octaves by blowing harder or softer. Your “octave key” on the flute is your flexible, well-trained embouchure. Instead of cranking up to gale force for the higher octaves, try pushing gently forward with your lips. (As a side note, if you find in doubling situations that your embouchure is tense and swollen when switching from reeds to flute, that’s a sign that you are playing reeds with too much tension.)
Sluggish technique. There are two main problems here that doublers bring to the table. The first is the habit of moving relatively large, heavy, stiffly-sprung keys. A flute’s keys are small, light, and move with a feather touch. The second issue is insecurity in holding the instrument. It can be hard for a beginner to get the instrument properly balanced (laziness about fingerings can contribute to this, too), and that will slow you down. If the flute keeps trying to roll out of your hands, rotate it a few degrees so the bulk of the keywork sits right on top of the instrument.
Sight-reading disasters in the third octave. Flutists play way up in the ledger lines as a matter of course. If you want to hang in the flute section, it’s time to learn to read those notes fluently. Stumbling around above the staff is also a sign that you haven’t really payed your dues technique-wise yet: you’re getting by within the staff because the fingerings are similar enough to saxophone and clarinet, but above the staff is a different story. Practice your scales and arpeggios.
Good flute playing doesn’t come from casual “dabbling.” Take the flute seriously, study it diligently with good instruction, and it will be a joy to play and a boon to your doubling career.