Tubular bells (also known as chimes) are musical instruments in the percussion family. Their sound resembles that of church bells, carillons, or a bell tower; the original tubular bells were made to duplicate the sound of church bells within an ensemble. Each bell is a metal tube, 30–38 mm (1+1⁄4–1+1⁄2 in) in diameter, tuned by altering its length. Its standard range is C4–F5, though many professional instruments reach G5. Tubular bells are often replaced by studio chimes, which are a smaller and usually less expensive instrument. Studio chimes are similar in appearance to tubular bells, but each bell has a smaller diameter than the corresponding bell on tubular bells.
Tubular bells are sometimes struck on the top edge of the tube with a rawhide- or plastic-headed hammer. Often, a sustain pedal will be attached to allow extended ringing of the bells. They can also be bowed at the bottom of the tube to produce a very loud, very high-pitched overtone.
The tubes provide a purer tone than solid cylindrical chimes, such as those on a mark tree.
Chimes are often found in orchestral and concert band repertoire. It rarely plays melody, instead being used most often as a color to add to the ensemble sound. It does have solos occasionally, often depicting church bells.
In tubular bells, modes 4, 5, and 6 appear to determine the strike tone and have frequencies in the ratios 92:112:132, or 81:121:169, "which are close enough to the ratios 2:3:4 for the ear to consider them nearly harmonic and to use them as a basis for establishing a virtual pitch". The perceived "strike pitch" is thus an octave below the fourth mode (i.e., the missing "1" in the above series).

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