Flutes and oboes are both members of the woodwind family, but they are dramatically different. They vary in construction material, color, shape, tone and keywork. Playing position, sound quality, use or absence of a reed and range are also notable points of divergence.
One of the most readily noticeable differences between the oboe and flute is the choice of materials from which professionals construct the instruments. Except for the metal keywork, the oboe usually is made from grenadilla wood, also called African Blackwood. More rarely, oboes are made from other woods such as rosewood. The body and keys of most Western concert flutes are rarely made of wood and instead are made from metals, most commonly silver-plated brass. Some professional-level players perform on nearly completely silver flutes, and some use gold in the mouthpiece lip rest joint or for the keywork, depending on the exact tone quality and aesthetics the player wants.
The oboe and flute differ in color because of the different materials used in construction. Oboes are black in color, with silver-colored keys. Flutes usually are totally silver-colored, but may have yellowish-gold coloring depending on the metal used.
No matter what materials are used in the construction of an oboe or flute, the shape of the two instruments is another distinguishing factor. A flute looks like a straight tube. The bore, or the internal chamber of the instrument through which air moves, has a cylindrical shape. Much of the oboe is looks round like a tube from the outside, too, but internally, the bore has a conical shape, tapering toward a flared bell. This flare is not found on the flute.
Looking at the keywork of the oboe and flute, the oboe has more keys and holes. The flute normally has at least 16 openings, while the oboe has a total of at least 22. The exact number of holes on either the oboe or flute depends on the exact model and grade of the instrument.
Moving toward the actual playing of the oboe and flute, a Western classical flute is a transverse, or side-blown instrument, meaning that it is held and played horizontally. This requires the player to hold the instrument to the right side. The oboe is an end-blown instrument. The player holds the instrument at roughly a 45 degree angle in front of his body, blowing downward into the top end.
Next, oboes are "double-reed" instruments. To make a reed, the oboist folds a piece of bamboo cane over a tube and ties it in place. He then clips the tip of the cane to separate it into two independent pieces. After the oboist has shaped the two independent pieces of cane that make up the whole reed, he puts the reed in his mouth and causes the cane to vibrate with a stream of air.
Flutes do not use reeds. Instead of making a reed vibrate, flute players blow air directly into the flute. The airstream from the player causes the air inside the flute to vibrate, and some of this vibration comes out of the flute's end and tone holes as pitch.
The bore of any instrument drastically impacts the overall tonal quality of the instrument because of the impact the bore has on the behavior of the air column. The use or lack of a reed also impacts the tone. Oboes can be very loud, piercing and a bit duck-like, but they also can sound extremely warm and sweet. Flutes sound either piercing or mellow, depending on their register, and they lack the somewhat sandy quality that results with a reed.
The range of the oboe and flute are similar, but the flute's range is slightly larger than the range of an oboe. The oboe plays between Bb3 and G6, although a more comfortable tessitura is C4 to Eb6. The flute's range is from B3 to C7, or roughly three octaves. Not all oboes extend to Bb3, however, and similarly, not all flutes have a foot joint long enough to produce a B3. Notes above these general ranges are possible, but they are not regularly played, are challenging in terms of facility and tone preservation and require absolute competence of the performer.