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Trumpet Mouthpiece Sizes & Numbers: 13 Questions (Answered!)

If you’re confused about the numbers and letters on your mouthpiece then you are not alone. It can be very difficult to figure out the difference between two trumpet mouthpieces.

I’ve played the trumpet for more than 30 years and I still had to spend several hours gathering the information for this article!

There’s a lot of nerdy talk and charts on the brand’s websites and they don’t do a good job of explaining exactly what the numbers and notations mean. I decided to create a good helpful resource on the topic.

So, here we go!

What do trumpet mouthpiece numbers mean?

The numbers on trumpet mouthpieces primarily relate to the size of the hole inside them, also known as the cup size. The bigger numbers typically represent mouthpieces with smaller holes whereas a smaller number means the mouthpiece has a hole with a slightly bigger diameter.

These three mouthpieces are (from left to right):

1) Vincent Bach 1 1/4 C

The number 1 1/4 refers to the width of the hole inside the mouthpiece. It doesn’t refer to inches – there doesn’t seem to be any logic to the number.

The first number “1” refers to the size of the cup (scroll down to see illustration below) and the lower the number, the bigger the cup size.

The second part “1/4” refers to how narrow the cup hole is. The closer you get to 1, the narrower. So, 3/4 is slightly more narrow than the 1/2 and 1/4.

2) B&S 2/3

From measuring the mouthpiece I’d say it looks a lot like the Bach 7C. There’s literally no information online about how B&S number their mouthpieces so I just gave it my best shot.

3) Yamaha 11C4-7C

With the Yamaha mouthpieces, we find that they follow a certain logic around the notation system. Japanese manufacturers seem to follow a certain system here. The “11” number refers to the inner rim diameter. The rim is the part that touches the lips while playing (scroll down to see illustration below). 5 is the smallest and 68 is the largest number here for Yamaha mouthpieces.

The “C” refers to the volume and shape of the cup (A is shallow, C is medium, and E is deeper).

Each brand has its own “logic” and formatting

The different brands all use different names and numbers when ordering the mouthpieces. This can make it very confusing for beginners to figure out which mouthpiece to use. It would be REALLY helpful if they could get together and agree on some standard notations.

There are no standards numbers or real logic that works across the different brands.

That’s why you cannot list all trumpet mouthpieces in a handful of categories as there are several parameters to take into account.

A wider mouthpiece will make it a bit harder to hit the higher notes but you get better control. A shallower mouthpiece, on the other hand, offers more range but also less control.

It’s typically easier for beginner’s to start out with a pretty wide mouthpiece.

The most-used mouthpieces are the Vincent Back models. Here we typically find the letters A, B, and C and the numbers 3, 5, and 7.

  • 7c – the most-used mouthpiece
  • 5c – slightly bigger cup than 7c (require more air)
  • 3c/3b – slightly bigger than 5c (require more air)

Is a 3C mouthpiece bigger than a 7C?

The Bach 3c mouthpiece has a slightly bigger cup than the 7c. The cup is the part that touches your lips and a bigger cup makes it easier to control the tone, but it also makes it more difficult to hit the high-pitched notes.

The 7c mouthpiece from Vincent Bach is the standard mouthpiece you get with your trumpet.

Many trumpeters shift from the 7c to the 5c or 3c to gain a bit more control and high range. Especially in the beginning as they get used to the instrument.

What is the difference between a 3C and 5C?

The cup size on the Bach 3c is a little bit bigger than the cup on a 5c mouthpiece. This allows the player to have a bit more control but it also requires more air and pressure on the lips.

Both mouthpiece sizes are very popular.

It all comes down to personal preference and style. There’s really no right and wrong when it comes to trumpet mouthpieces. It largely depends on embouchure and the anatomy of your lips and the position of your teeth.

That being said, you probably want to start with a 3c or 5c if you’re still a beginner.

Are trumpet mouthpieces universal?

Trumpet mouthpieces are universal in the sense that they can be used across different brands and trumpet sizes.

It’s perfectly fine to use a Bach mouthpiece on your Yamaha trumpet (in fact, that’s exactly what I do!) and you can also use other mouthpiece brands across all the different trumpet models and brands.

However, trumpet mouthpieces are not universal when it comes to the terminology.

The numbers and letters can be rather confusing for beginners, so let’s take a deeper look at what you need to know to understand the differences between the different mouthpieces.

Can I use a trumpet mouthpiece on cornets and flugelhorns?

You can use a trumpet mouthpiece on any cornet or flugelhorn. The diameter of the mouthpiece receiver (where you insert the mouthpiece) is not exactly the same size but the shank compensates for that. The shank is the part of the mouthpiece that you insert into the trumpet and it’s between 0.382” and 0.390”.

You can use the same mouthpiece across these horns even though the size of the lead pipe varies (where you insert the mouthpiece).

Can you use a cornet mouthpiece on a trumpet?

You can use a cornet mouthpiece on any trumpet model. The tip of the mouthpiece is smaller so it will stick a bit further into the trumpet, and that’s not a problem. It’s not advisable, however, as it will not produce the big sound you normally associate with a trumpet.

If you are stuck with a cornet mouthpiece you can definitely use it with the trumpet.

The mouthpieces are constructed in a way that you can insert a cornet mouthpiece a bit deeper into the trumpet to account for the slightly thicker pipe.

However, you should not expect the same tone. You might find that you can more easily hit the higher notes with a cornet mouthpiece on the trumpet (or on the flugelhorn, for that matter).

What is the standard trumpet mouthpiece size?

The most commonly used trumpet mouthpiece size is probably the 7c mouthpiece from Vincent Bach.

The Bach company is the largest manufacturer of mouthpieces for trumpets and the Bach trumpets all come with the 7c mouthpiece as standard. This means that the Vincent Bach company has decided on the 7c to be the standard.

As we looked at above, the 7c is a bit harder to use for some people. The cup is a little bit smaller than the 3c and 5c and that means you need more practice to control the tone well.

What is the largest trumpet mouthpiece?

The Vincent Bach 1 mouthpiece has the largest cup diameter which means there’s a larger cup hole. That makes it easier to control the sound but the high notes are more difficult to reach.

This mouthpiece is also sometimes referred to as a 1a mouthpiece.

A mouthpiece like the Bach 1 requires a really strong embouchure and lots of training. However, it can also be a good choice for trumpeters with really big lips.

What is the smallest trumpet mouthpiece?

The Bach trumpet mouthpiece with the smallest cup size is the model 3. It has a hole diameter (cup size) of only 16.30 mm which is the smallest of the trumpet mouthpieces. However, the depth of the hole is bigger to compensate for this.

This mouthpiece is not used much as the small cup size makes it hard to control the tone well. Especially for the high-pitched notes.

How to determine the trumpet mouthpiece size?

You can measure your mouthpiece with a caliper. You measure the thickness of the rim around the cup, the cup hole, and finally the depth of the cup itself. Then you have the basic numbers and you’re to figure out which size your mouthpiece is.

The size of the cup determines how bright or dark the tone will be.

A flugelhorn requires a larger cup diameter and a deeper cup hole whereas the smaller cornet (especially the tiny Es cornet) requires a smaller cup diameter and shallower cup hole.

What is the mouthpiece on a trumpet called?

The mouthpiece on a trumpet is simply called “a mouthpiece”. It doesn’t have another term for it. The outer part of it that touches the lips is referred to as the “rim” and the inner part is the “cup”. The cup leads to the shank which is the part you insert into the trumpet lead pipe.