Woodwind instruments can be overblown by blowing them harder (increased blowing pressure and / or particularly rapid increase in blowing pressure), which increases the tone produced with the same fingering.
Instead of blowing it differently, the result can also be achieved by partially opening a tone hole - or opening a small hole specially designed for this - causing an additional vibration node to form within the air column , with the grip otherwise unchanged . This is the effect of the partially open thumb hole on recorders or octave keys, e.g. B. with the oboe. This is also known as overblowing and is used regularly on many woodwind instruments.
The various pitch ranges of an instrument achieved by overblowing, which differ in sound to a greater or lesser extent, are also called registers .
Open flutes (e.g. transverse flute , recorder ) and reed instruments with a conically drilled tube (e.g. oboe , shawm , saxophone ) overblow from the first partial (the fundamental) to the second partial, which is an octave higher, and at stronger overblowing into the following natural tones. Covered flutes and reed instruments with cylindrically drilled tubes (e.g. clarinet , krummhorn , duduk ), on the other hand, overblow from the fundamental to the third partial, which is a duodecime higher.
In practice, the first three to a maximum of five natural tones are used on woodwind instruments. However, instruments in the bass range can often be overblown on their lowest key notes (in which the vibrating column of air is relatively long compared to the diameter) up to the eighth natural tone and beyond. With instruments in higher registers, the ability to overblow into higher natural tones decreases with increasing altitude. Very high instruments such as whistles often cannot be overblown at all.
With brass instruments , overblowing primarily refers to the generation of the higher natural tones . Brass instruments sometimes overblow up to the 24th natural tone, e.g. B. the natural horn , the natural trumpet or the baroque trumpet . Until the invention of the valve at the beginning of the 19th century, the musicians of these instruments had to make do with the supply of intonatable natural tones .
Sometimes overblowing is also used to describe the "thudding" of a brass instrument with extremely high dynamics . This effect is based on the fact that a natural oscillation of the horn (falls) occurs and can be used well on horns with a large horn, e.g. B. French horn , Parforcehorn , Trompe de Chasse , realize.
In the case of an organ pipe , overblowing also describes the effect that occurs when it produces an overtone instead of the fundamental . In this case, an open overblowing whistle generates the second partial tone, the octave , a gedackte overblowing pipe the third partial tone, the twelfth . A common overblowing organ register is the flûte harmonique .
- How Do Woodwind Instruments Work? (English) - scientific treatise on modern woodwind instruments (flute, oboe, bassoon, clarinet, saxophone) of the University of New South Wales (with sound samples)