Final answer:
The clarinet and oboe have distinct timbres mainly due to differences in reed type and bore shape. The clarinet uses a single reed and has a cylindrical bore, while the oboe uses a double reed and has a conical bore.
Step-by-step explanation:
The two main differences between the clarinet and the oboe that give them distinct timbres are the reed type and the bore shape. The clarinet uses a single reed attached to a mouthpiece, whereas the oboe uses a double reed with no mouthpiece. This difference in reed type significantly affects the sound production and quality of each instrument. Additionally, the bore of the clarinet is cylindrical, leading to a timbre that is smooth and focused, while the oboe has a conical bore, contributing to a richer, more penetrating sound with a broader spectrum of overtones.
The variety of overtones and their intensities, which result from the different bore shapes and reed types, create the unique sound characteristic of each instrument. When played, the length of the tube can be altered by opening and closing finger holes to change the pitch, but it is primarily the construction differences in the bore and the type of reed used that are responsible for their distinct timbres.