Mutes From Monteverdi to Miles:
The story of brass instrument mutes from before Monteverdi to Miles and beyond.

What is a mute? 

A mute is a device inserted into the bell of a trumpet to either make the tone produced softer, to change the tone quality, and with the Baroque trumpet, to change the tonality. The most common types of mutes are the straight mute, the cup mute, and the wah-wah mute. Other mutes that fit over, not inside the bell, are the plunger mute, and different types of hat mutes.


The criteria for selecting a mute for any player are: the mute should have good overall intonation, should be playable in all registers, should have good response at any dynamic level and have a characteristic muted sound.

Straight mutes will generally fit any Bb or C trumpet bell. The mute should be playable to the low F-sharp. If the low register does not respond, the corks should be sanded down gradually until the low F-sharp responds. Because the B-flat trumpet can play a whole tone lower than the C trumpet. corks on a B-flat trumpet mute have to be a little lower, allowing the mute to go farther into the bell.

A mute that is slightly sharp overall is better than a mute that is generally in tune but with several bad notes.

Cup mutes tend to be in tune or slightly flat, depending on the mute, the trumpet, and the player.. The cup mute should have the cup relatively close to the bell, about an eighth to a quarter of an inch of space, depending on the softness and the “cup” sound desired. Some mutes have an adjustable cup; others have to be permanently adjusted by sanding down the corks a little at a time to achieve the right fit. When so adjusted, the cup is only good for trumpets of similar bell sizes.

Wah-wah mutes tend to be sharper than straight mutes. Some wah-wah mutes are too small. They have insufficient interior volume to play well in the low register, often not being usable below low B-flat concert. Using the wah-wah mute without the stem also creates problems with some brands of mutes. One should be able to play to the low F-sharp on the B-flat trumpet with the stem-cup removed. An extra piece of brass or cardboard tubing, 1/4 to 3/4 inches long, to extend the interior tube of the mute, will help if the low register does not respond. Harmon or wah-wah mutes should fit any standard B-flat or C trumpet bell. Some bell curves may make it difficult for the mute to stay in the trumpet wah-wah mutes that fall out can be treated by rubbing a very small amount of violin bow rosin on the corks.

Different types of metal definitely affect the mute’s tone quality and response, much as different metals used in a bell affect a trumpet’s tone quality and response. It is very difficult to describe what these differences are, however. One person’s “dark” is another person’s “dead”; another person’s “bright” is someone else’s “tinny.” To me, the Tom Crown all-aluminum straight mute is bright, the brass-end mute less bright or somewhat dead, and the copper-end or the all- copper mute is dark.

What does it mean when the part says “muted”?

“Muted” generally means with a straight mute. Sometimes the texture of the music suggests the use of something other than a straight mute, and a cup, wah-wah or other mute is more appropriate.


The muted passage for three trumpets in Fetes by Debussy is usually played with a very soft mute, such as the Shastock “Whispa” mute. Now it can also be played with Tom Crown practice mutes. The ideal volume should be that the woodwinds, when they play the same passage after the trumpets, sound much too loud.


My model A mute is very good for a variety of soft passages, and ideally one should have two such mutes, one with the corks lower than the other, the one mute for normal use and the other for very soft passages. The very low corks do not significantly effect the intonation.

What type of mute does one use for the Gershwin Concerto in F or An American in Paris? “With felt crown” is indicated A felt crown is the crown of a fedora hat, usually without the lining or brim. Slits are cut so the hat will stay on and over the bell. This gives the “jazzy” muted sound that Gershwin must have heard from jazz trumpeters of his time.

What is the life expectancy of a mute?

Metal mutes, if they are not stepped on, run over by a car, or otherwise destroyed, should last more than the life time of the player. Corks are also very long lasting. Cork is not affected by extremes of temperature or humidity. Corks do sometimes break if part of the glue holding them to the mute separates or if there is uneven stress on the cork. Glue used to re-glue corks to the mute should be a non-water based, non- flammable contact cement, such as Duro, 3M, or other brands available at most hardware stores.


I often meet professionals who still have and use mutes they have had for twenty or more years, but some students think a mute is beyond hope if a cork comes off or the mute is no longer shiny. Dents should be avoided, although I know professionals who use mutes that are completely covered with dents. Small dents usually have no effect on the sound of a mute. Mute dents can be removed by brass repair shops, but this is usually more expensive than buying a new mute. Metal mutes with an out of round opening can be improved by forcing the mute opening back into round with the shank of a discarded mouthpiece. Mute timbres are very subjective. A player should experiment with mutes the same way we all experiment with trumpet equipment to arrive at what will be satisfactory from the end of the bell to the back of the hall.

When did mutes appear?

The Toccata from Claudio Monteverdi’s opera L’Orfeo (1607) is the first appearance of the trumpet in an orchestral score and the "Clarino con tre trombe sordine" called for indicates that the trumpets were all muted. The Toccata is preceded by the instructions “E si fa un tuono piú alto volendo sonar Ie Trombe con Ie Sordine”, a warning that the trumpets will be using mutes and that the pitch will thus be a whole tone higher. The earliest mutes had the effect of shortening the overall length of the trumpet by completely closing the trumpet bell at the point of contact, with the sound going through a hole in the center of the mute. These mutes raised the pitch by a half or whole tone depending on the size of the bell. At some point, probably around the time of Mozart’s Idomineo (1790), mutes that didn’t change the pitch were invented or discovered. Since then the ideal is a mute that doesn’t disturb the orchestral fabric by being too sharp or flat. Most modern mutes fulfill this ideal.

The article "What is a Mute" was adapted from a contribution by Tom Crown to Gabriele Cassone's La Tromba.