Material and finish affect more than the looks of a saxophone. Since the quality of the sound depends on how the musical vibrations resonate in the body of the instrument, the material of that body can make a huge difference in the character of its voice.
The clarinet belongs to the woodwind family; but despite the name, not all clarinets are made of wood. The sound is produced by blowing air past a wooden reed, which causes the air to vibrate in a thin column, a part of the instrument known as the "resonator."