Bass Drum
　　Bass drums refer to drums with doulbe skins. They are used more often in western percussion. The two heads of the drums were made by animal leather, but now they are made by plastics or fiber. The bass drums were orignially made of wood, but along with timpanis and snare drums, they are all made of synthetic fiber now.

The bass drums could be categorized in the following:
•The bass drums used in orchestra are mounted with suspension drum racks.
It is called "concert bass drum" in English, this kind of drum is used in the orchestra, which ranges from 32 to 40 inches in diameter, and is often 36 inches. The depth for the concert bass drum is often 16 to 20 inches. The sound of the instrument is thick and low, with longer lingering sounds. Players perform the concert bass drum with strikings of mallets and mount the t drums with suspension or sit drum racks.

•The bass drums used in the drum sets are often played with pedals.
They are often used in jazz music and, instead of mallets, they produce sounds with the control of pedals. The bass drums in jazz are 14 to 22 inches in diameter and 12 to 18 inches in depth. Since the diameter and the depth of the jazz bass drums are similar and their diameters are shorter than other bass drums, their sounds are sharper and with shorter lingering. With the pedaling control, every strike of the bass drum is similar in place, which makes the sound more unified.
• Bass drum player in marching bands wear special clothes to hold the drums.
The bass drums in military bands or marching bands are similar in structure as those of the concert bass drums, but with smaller size. They are about 16 to 32 inches in diameter and 12 to 18 inches in depth. One to four drums could be played in these bands and the drummers have to strike the drums while moving with the team. Since the bass drums could not be fixed on the ground or pulled by movable pulleys, drummers have to wear speacial clothes to hold the bass drum in front of their bodies.