The Complete Guide to the Parts of a Trombone

When you’re interested in something, say for example an instrument like a Trombone, you’d ordinarily want to know everything about it down to the tiniest part of it.

And by interested, we meant the same level of unconditional love for the instrument just like this guy right here. (If not, then thank you and see you next time!)

And what better way there is for you to find out than disassembling the instrument and taking a mental note of each part? I mean how do you think doctors learned all about our anatomy?

And unless you’re a trained medical professional or a seasoned musician, we strongly recommend against dissecting a human body or a fully functional trombone.

Hence, we assembled this article so you’ll know about the following…

  • The history and origins of the Trombone
  • The three major parts of the instrument
  • All the small parts that give great contributions

Overview of the Trombone

The trombone’s body is a long, cylindrical tube that’s about 9 feet in length, doubled over, and fitted with braces that do the job of maintaining its structure.

Like the trumpet and French horn, the trombone is a member of the brass family of instruments. It produces sound by having the players buzz their lips into a mouthpiece attached to a long, metal tube called the bore before eventually flaring into an opening called the bell.

You can see that it has the same basic design as its early predecessors as pictures in this tweet:

The parts of a trombone are mostly made of yellow brass, which is a mix of 70% copper and 30% zinc. On the trombone, the mouthpiece can be removed from the body, as with most modern brass instruments.

On a side note, the material really plays a big role in determining the best bass trombones here.

What makes the trombone unique from other brasses, however, is its method of changing pitch. Most brass instruments, including the trumpet, French horn, and tuba, change their pitch when the performer depresses a key or valve.

Other Brass Instruments

To have a better insight, don’t forget to skim over this article that compares the trombone to the tuba.

The trombone, in contrast, has no keys or valves. Instead, trombones change pitch through the use of a long, movable portion of the metal tube called the slide.

When the performer extends the slide, the pitch goes down. Pull it back in, the pitch goes up. It’s that simple!

Parts of a Trombone

The trombone is separated into three distinct sections that are easily the largest parts of the instrument. Within each of these sections are several different, less-sizeable parts that are still no less important.

Bell Section

The largest part of the trombone. Those who aren’t even familiar with the said instrument can quickly point the bell thanks in part to the word’s intrinsic meaning which is “a deep inverted cup that widens at the lip.”

You can also see that different types of trombones have different bell sizes. Just take a look at this article that does a side-by-side comparison of the bass and tenor trombone.

The main reason can be attributed to the trombone’s most basic design: a cylinder. A cylindrical design means that an instrument is pretty much even throughout the length of its body and only expands when it finally reaches the bell.

Cylindrical and Conical Designs

Unlike instruments with a conical design, one can quickly discern where the trombone’s bell begins at the point where the tube dramatically flares out.

The function of the bell is to project or amplify the sound is being produced by the player. For this reason, the bell is also the perfect place to attach mutes which are accessories used to change the sound by making it quieter.

Now, here are the parts that compose the bell section.

Slide Receiver

This is the junction where the fitting of the slide is inserted. After combing the two sections together, they are locked in place using a tightening bolt.

Trombone Bell Section

Bell Braces

They are found towards the end of the instrument where the tubing bends into a “U” before flaring out into the bell.

The job of the bell braces is to support the tubing to make sure that it does not collapse by the weight of its bell.


The counterweight is located towards the rear-end of the trombone. It looks exactly just like a small hockey puck and is securely held by the farthest brace behind the player.

Without a counterweight, players will find playing the trombone for long periods difficult thanks to the instrument’s sheer size and awkward design that puts much weight in the forward sections.

Tuning Slide

The tuning slide is located on the heel or the rear-most part of the instrument that constitutes the U-shaped bend of the trombone.

This movable piece is used to fine-tune the sound produced by the instrument. It can be slid in and out with just a little bit of pressure.

What the tuning slide does is adjust the pitch by making the tubing slightly longer or shorter.

By doing so, pulling the slide out will lengthen the tubing so the instrument will sound lower while pushing it in makes the tubing shorter, thus resulting in a sharper pitch.

But here’s the thing, if you get to the level like these players right here, you might find the tuning negligible and rely instead on your embrasure adjustments to get the note right.

Also do not forget to clean your tuning slide. Brass Recordings told us how to do it right. Check it out!


Well, if there’s one thing that stands the most out of this instrument, then that would be the slide.

The trombone is pretty much the only prevalent instrument that uses a telescopic sliding mechanism. The longer the tube, the lower the note; the shorter the tube, the higher the note.

One thing to remember about the trombone’s slide is that it is frequently made using the lightest metal possible of any musical instrument. The metal used in its construction ranges from .007 to about .012 of an inch thickness.

Because of this, it is highly recommended to keep the instrument safe from any bumps and falls and must be safely put in its case when you’re not using it.

Adding to it, the sliding mechanism has two main components: the inner slide and the outer slide.

Slide Mechanism

Find out all the parts of the slide in the list below.

Inner Slide

The inner slide is enclosed by the outer slide through a telescopy connection. This piece is thoroughly lubricated to enable the smooth movement of the two components.

The inner slide also contains the fitting used in connecting the telescopic assembly to the bell section of the instrument.

Outer Slide

The outer slide’s diameter is slightly larger than the inner slide’s size to allow the sliding motion without making the instrument extra bulky.

This is also the piece that a trombonist controls to vary the pitch of the instrument.

Slide Braces

They are what you might call the “anchor points” or the “handles” of the instrument.


These are found just in front of the mouthpiece and are used to increase the strength and rigidness of the sliding mechanism.

The first slide brace, the one closest to the mouthpiece is attached to the inner slide while the second slide brace, is located out in front and is affixed to the outer slide.

When playing, a trombonist grasps the first slide with their left hand to keep the instrument in place while they use their right arm to move the second slide either inward or outward to play the desired note.

Water Key

If you’ve been playing any wind instrument for far too long, you should know by now just how much saliva will accumulate inside your instrument.

The good thing is that the water key is there to keep your saliva from overflowing.

Commonly known as the spit valve, the water key is a small outlet found towards the front of the trombone.

It is controlled by a tiny lever that opens a small hole in the slide to drain accumulated saliva or any kind of moisture out of the instrument.

You can learn how to install it by watching this video. It shows how to install it on two trombones: it is easy but sometimes it is more difficult – depends on your trombone.

Slide Lock

Allowing the trombone to slide in and out even if it’s not your intention will be highly detrimental to the instrument. Just imagine picking up the instrument and having the outer slide fall off and bending out of shape and making it unusable.

This is exactly why the slide lock exists to prevent that from happening. It consists of a small latch that keeps the outer slide in place.

This important safety feature prevents you from causing a costly accident so make sure to remember it!


Also known as the stopper, the bumper is a small rubber notch that is found on the very tip of the slide. It is another safety feature that protects the trombone from unlikely damages.

The shop ensures that there is a bit of a cushion in between the slide and the ground whenever you’re resting the trombone on the floor.

Additionally, it also provides much-needed friction to stop the instrument from slipping away whenever you’re in the middle of a lengthy bar’s rest.

If you want to prevent your trombone slide from damaging inside use bumper corks. Watch this video to learn how to install them.

Mouthpiece Receiver

Just as its name implies, the mouthpiece receiver is used to refer to the fitting to which the mouthpiece is attached to the instrument.

It is located on the end of the slide that’s nearest to the player.


The mouthpiece looks like a miniature funnel and is the part of the instrument where a player blows air into.

It comes in different sizes and even comes in different variations that trombonists can freely choose depending on the type of music that they’re about to play.

In general, smaller mouthpieces produce a brighter sound and make playing in the high register comparably easier.

However, different manufacturers have their ways of identifying the measurements of their products. To help you understand more about that, here is a quick primer on the subject just for you.

Parts of a Mouthpiece

Below is a list of the different parts of the mouthpiece.


The rim is the circular edge of the mouthpiece to which the player presses their lips. Its shape has a significant influence over the range and tone quality that a player can achieve.

For example, a flatter rim is easier to play compared to that with a more rounded rim. However, the latter does not give much room for shaping the tone while the latter is more rewarding in its range.


The cup refers to the depth that immediately follows the rim. This also contributes to the overall quality of the sound as well.

Different cup depths can offer different sound qualities to the instrument. But the thing to remember here is that the bigger the cup, the deeper and more mellow the sound will become.

In contrast, smaller cups account for brighter, sharper tones and generally make it easier to play in the high register.

Mouthpiece Inside


The throat is the hole found in the bottom of the cup. Its diameter dictates the amount of air that passes through the mouthpiece and into the rest of the trombone’s body.

It is directly proportional to the size of the cup. Meaning, a larger cup will come with a larger throat and a smaller cup will also be accompanied by a smaller throat.


Also known as “the bore”, this short tube is the one that attached the mouthpiece to the slide.

This too affects the sound quality that the trombone can produce. Larger bores tend to have darker sounds and are better suited to play orchestral music.

On the other hand, those with smaller bores create sharper sounds and perfectly fit the sound that can be heard in jazz, pop, and reggae.

Valve attachments

As we have said earlier, trombones do not come with valves just like the rest of the brass family do. But there’s always an exception:  the instrument somehow gives the option to players to attach valves when necessary.

These valves, also known as F attachments, will affect the musical range, the slide positions, or even a combination of the two. Here are the different types of attachments that are available to the trombone.

Open Wrap and Closed Wrap F-Attachment Trombones

Open Wrap

This type of attachment increases the overall length of the instrument. It has as few bends as possible and allows for a more open sound with lesser resistance.

Simply put, it makes it easier to play the instrument by reducing the force required to make a sound.

Closed Wrap

The exact opposite of the Open Wrap attachment. It is integrated within the bell section and contains more corners.

It provides greater resistance which means that each blow requires a greater force to make a sound.

And if you become really good at it, you can even try and execute stuff just like this:

Useful Links


So there you have it! We’ve just completely dissected a trombone without physically dismantling it. Whatever the case, it is important to remember that the trombone is a super delicate instrument, and extreme care and prudence are needed when handling it.

If you have any more questions about the parts of a trombone or maintaining the instruments, feel free to leave a comment below and we’ll get back to you with the answers.

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