To produce sound, musical instruments need air. Your tone and intonation quality depends on your posture, breathing technique, and embouchure. Proper breathing technique begins with your posture, which refers to sitting or standing while playing your instrument. To breathe without tension, it's crucial to maintain balance while sitting or standing. The following stretches prepare the body for playing. They are then followed by checkpoints for standing and seated positions.
To ensure you have sufficient air, it's important to engage your diaphragm. You can locate your diaphragm by contracting your abdominal muscles, inhaling, and expanding your belly outward. This causes the diaphragm to move downwards. When you exhale, gently draw your stomach inwards. It's not necessary to feel a lot of tension while breathing normally, but this is an effective way to feel the diaphragm at work.
After experiencing the diaphragm in action, avoid overthinking it. The best way to determine if you're breathing with ease is to use your aural and tactile senses. This is referred to as monitoring. Place your hand perpendicular to your lips while forming an "oh" shape with your mouth. As you inhale, listen for a complete, resonant, steady, and uniform sound.
There are MANY factors that will cause intonation issues, and there are also MANY solutions that will help alleviate them. Learning how to diagnose and correct the issue is a continual learning process for every musician. Click on a link below to learn more about the intricacies for each instrument.