Saxophones are brass metal but count as woodwinds
Wind instruments vibrate a trapped air column, yet family labels follow sound production, not material. Saxophones are usually brass metal with a reed, so they sit with woodwinds. Wooden cornetts and ivory olifants buzz lips like trumpets, so organology files them as brass. Hornbostel-Sachs simply calls the whole group aerophones.
A player blows into or across a mouthpiece on a resonator tube whose sounding length sets pitch. Brass instruments vibrate the lips; woodwinds either flex a reed, split air on a fipple, or cut an open embouchure edge as flutes do. Classification ignores whether the tube is wood, brass, plastic, or ivory. Reed valves reflect high-pressure pulses so standing waves form odd quarter-wavelength multiples with a pressure antinode at the mouthpiece. Lip-reed brass works similarly when lips close most tightly on arriving low-pressure pulses.
Air-reed flutes and recorders drive a thin jet across a labium. Pipe oscillation perturbs the jet; jet instability amplifies the wobble until reaction force on the edge sustains the note—Alan Powell's edgetone studies quantify that unsteady force. Because the wall need not vibrate, gold versus silver flute material is acoustically secondary. Open-open air-reed tubes favour half-wavelength multiples. Roughly, a forty-centimetre reed or lip-reed tube resonates near 220, 660, and 1100 hertz, while an air-reed tube of similar length sits near 440, 880, and 1320 hertz.
Players change pitch with separate tubes (pan flute), valves or slides that lengthen brass tubing, side holes on woodwinds, or harmonic overblowing—usually combining methods. Bells couple brass bores to free air and reshape resonances; on woodwinds they mainly even the lowest notes that vent there. Temperature shifts air density and speed of sound far more than metal expansion, so winds go sharp or flat with the room. High-resistance playing can raise intraocular pressure; a 2011 study saw dramatic temporary IOP swings, and Native American flutes generally demand lower oral pressures than classical Western winds.
Source: Wind instrument
