technique is very demanding. At the pedal level, it is nearly impossible (as in the final movement of Tchaikovsky's Symphony No. 6). To remedy this, a small mute made of brass, with a small branch and tiny brass bell, is substituted for the hand. It still takes an enormous amount of air to achieve the "stopped" sound, but is certainly possible for an experienced player. Stopping, whether accomplished by hand or with a mute, raises the pitch to such an extent that horn players have traditionally transposed the muted notes, fingering a half-step lower than written, but a line of self-transposing stop mutes have recently been developed in Japan.
Plunger mutes are simply unused rubber sink or toilet plungers with the wooden handle removed (but can be purchased from certain mute companies). Some musicians cut holes in the rubber to alter the sound produced. Plungers are often used in a manner similar to the hat mute, where the musician manipulates the plunger in front of the bell while playing with their other hand. A "closed" plunger gives a tone similar to a tightly inserted cup mute, and a skilled plunger technician can often produce sounds similar to the human voice.
In Duke Ellington's orchestra, trombonist Tricky Sam Nanton was noted for his work with the "plumber's friend". The Glenn Miller band made a wooden red and white plunger popularly called the "Tuxedo Plunger" (used in the band's hit tune "Tuxedo Junction"). For a combination of straight mute sound with the readily manipulated plunger, Pixie mutes are used. More recently, some players use a plunger made from a dog toy called the "Jolly Ball Tug-n'-Toss" cut in half.
This mute is similar to a straight mute, but is generally used with a plunger mute to get a "dirtier" sound. It was a favorite of Sam Nanton of the Duke Ellington Orchestra.
Practice (whispa, whisper, or hotel)
Practice mutes, also known as Whispa, whisper, or hotel mutes, are similar to straight mutes in appearance, but have a solid ring of cork that prevents air from escaping from the bell like a Harmon mute. There are sound baffles inside the mute, and tiny holes in the sides of the mute that allow air to escape silently. These mutes are extremely quiet and are rarely used in performance. They are usually used for privacy and to avoid disturbing bystanders during practice sessions.
The trumpet playing community has embraced a method for making an inexpensive practice mute out of a conical plastic "Renuzit" brand gel air freshener container filled with tissue or fabric. The mute is held in the bell with weatherstripping. The self-assembly allows each player to custom-fit the mute to the bell of their trumpet, or alter the sound quality and muffling effect.
Yamaha produces an electronic practice mute system known as Silent Brass, with models for tuba, euphonium, horn, trombone/bass trombone, alto trombone/flugelhorn, trumpet/cornet, and piccolo trumpet. It consists of a practice mute with a built-in microphone and 1/8th inch jack, which connects to a pocket amplifier with volume control and headphone output. It is sometimes used in combination with effects pedals or other devices to completely change the sound of the instrument.
Sound from woodwinds emanates mainly from the holes in the instrument's body. Muting woodwind instruments is very uncommon, and in the case of the flute is almost unknown. In the 18th century purpose-built mutes existed for the oboe and clarinet, but in the rare cases when one of these instruments is muted today a handkerchief is usually stuffed up the bell resulting in a muffled sound. Some bassoonists still use purpose-built mutes, generally as a way of regulating volume at extremes of the instrument's register.
There exist saxophone mutes which are usually made of a soft material (such as velvet, silk or chenille) woven around a hard inner ring (usually brass or plastic). This mute is placed in the bell, most commonly perpendicularly to the body of the saxophone. This softens the tones of the saxophone somewhat, and can be useful in classical settings as it also dampens 