Musicians who play members of the brass family like the trumpet often try to distort the instrument's output into distinctive tones or sounds. One way to accomplish this is with the use of trumpet mutes, which can alter the music temporarily or silence the sound altogether for short durations. Depending upon what kind of sound alterations the musicians desire, they can choose from three main categories of mutes — straight, cup, and Harmon mutes. Most trumpet players who like to experiment with style prefer to collect as many mutes as possible in order to increase their versatility in sound and genre.
Known for producing a buzzing type of distortion, straight mutes are among the most common additions to a trumpet player's gadget arsenal. The conical shape of these trumpet mutes resembles the instrument itself and produces effects when inserted into the trumpet's bell and held in place with cork. Straight mute construction includes a number of primary materials such as cardboard, brass, or an amalgamation of different elements. Musicians on a budget often choose straight mutes made of aluminum over more expensive brass mutes due to their affordability and good sound production. Cardboard straight mutes — also known as stonelined mutes — make a good choice for students or beginners.
A cup mute also features an array of construction materials and techniques. This mute looks somewhat like a straight mute with the exception of a broad cup shape on the end that slides into the trumpet's bell. The most distinctive feature of these trumpet mutes is a rounded edge around the cup's lip which allows air to escape from the bell of the instrument. Aside from appearances, the main difference between straight and cup mutes is the sound output. A cup mute still produces a buzzing sound, but it's softer and more musical than the sound of a straight mute.
Also known as "wow-wow" or "wah-wah" mutes, Harmon trumpet mutes come in two separate parts and are usually made of aluminum. A long, cylindrical stem piece fits inside a larger, bell-shaped piece which slides into the trumpet bell. Musicians enjoy a lot of diversity with this mute and can play it with the stem fully or partially inserted in the trumpet bell. Many trumpet players also use their free hand to open or close the mute as they play, resulting in the "wah-wah" sounds associated with blues, jazz, and rockabilly musical genres. Some jazz and blues bands use Harmon mutes for all or part of the brass section.