Accents are produced through a combination of firm articulation and an increase in volume and speed of air through the instrument using the abdominal muscles. The quicker the muscular movement, the more violent the effect on the sound is. A very hard attack is likely to cause the note to overblow to a higher pitch, often creating a harmonic multiphonic. Alternatively, a more gentle attack creates longer tenuto accents, colouring the required notes to bring them out of the texture.
Accents using the abdominal muscles
Using the abdominal muscles, the effect in the recording is similar to that of a slowed down vibrato, creating pulses in the sound. This requires a moderate amount of muscular movement. This may be used to a varying degree to create a range of different sounds, as described above.
Notation of accents
Accents may be notated in a number of different ways, and may be performed at varying intensities. The example below shows a standard accent (beat 1) and two strong accents which require fast movements of the abdominal muscles.