Flutes have gone through a lot of changes over the years. One of the best additions has to be the C# trill key.

The key can do a lot, and it becoming more common. That means you don’t need to go with a specific brand to get it.
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Overview of the C# Trill Key
The C# trill key is an extra key on many flutes but is quickly becoming standard, at least on intermediate and professional models. It comprises a lever next to the Bb lever and a tone hole above the B tone hole on the back of the flute.
There’s a rod connecting the two so that you can open the key. That allows you to trill from a B natural or C natural to a C sharp or D flat. You can use those fingerings in the first and second octaves.
Ways to Use the C# Trill Key
If your flute has a C# trill, you can get a lot of uses out of it. Compared to other add-ons like a split E, the C# trill is much more versatile.
Here are some things you can do with the extra key.
Trill to a C#
As the name suggests and as I mentioned, you can trill to a C# more easily. If you don’t have the key, trilling from a B or C to a C# or Db is awkward.
You have to move the first finger of your left hand up and down. That can make your flute feel a bit less stable.
When you have a C# trill key, you just have to move your right index finger. It’s a lot easier to sustain a trill that way without feeling like you’ll drop your flute.
High G to A Trill
It also comes in handy in the third octave. You can finger a high G and trill the C# trill key and the first trill key to trill to a high A.
Other trill fingerings exist. However, they’re either more complex, or they’re more awkward. If those aren’t the case, usually one or both of the notes will be out of tune.
Using the C# trill key and the first trill key is a basic trill fingering for flutes with the spec. It’s easy and sounds good, and it comes in very handy.
Hold a C#
The key isn’t just for trills because you can achieve a more in-tune C#. So if you need to hold that note for a long time, you don’t have to manipulate the pitch as much.
One place to use this is the opening solo to Debussy’s Prelude. It’s a big orchestral flute solo, and it starts with a C# that you hold for five beats. That means getting a good sound and good intonation is vital.
The second movement of the Mozart Concerto in G also has a C# that you have to hold, though not as long. Still, it’s nice to finger a C natural and add the C# trill key to get a good sound.
Why Get a C# Trill Key
Maybe you’re about to shop for a flute, but you’re not sure if you’ll use a C# trill key. There are multiple reasons why you might want to get it on your next flute.
Here are a few things to think about before buying a flute without the spec.
Multiple Uses
As you can read above, the C# trill key offers multiple uses. That means you should be able to take advantage of it at some point in your playing.
You might not use it in every piece. However, you can use it in a lot of pieces, and you can incorporate it into your warmup routine.
If you think you may keep your next flute for a while, it makes sense to get as many specs as you can. That way, you won’t regret your purchase in a few months or years.
Becoming Standard
I mentioned this briefly, but the C# trill key is gaining popularity. In a few years, it will probably be pretty standard. Beginner flutes might not have it, but I imagine advanced models will.
Now, flutes have changed a lot over the years. Plenty of players have vintage flutes that don’t have a ton of specs, and they do just fine.
However, if you think you may want to sell a flute, having a C# trill is great. You might get more money for the sale. It could get harder to sell a flute without the crucial spec, especially if it doesn’t have any other special features.
Future-Proof Your Flute
Perhaps you don’t plan on selling the next flute you buy. Getting a C# trill can still be a good idea. If you’ll play the flute for many years, you might regret not getting the spec.
Composers might continue to write more difficult pieces. More and more of the rep could benefit from having the key.
If you don’t get the trill key now, you could lose out later. So keep that in mind, especially when buying your forever flute.
Why Not Get a C# Trill Key
As much as I love having the key, I’ll admit the C# trill isn’t perfect. If you’re looking for your ideal flute, you might not want the extra key.
Here are a few reasons to test the spec to decide if it’s for you.
More Expensive
Some flutes come with a C# trill at the standard price. But for those models that don’t the spec can significantly increase the price.
Let’s use my professional flute, a Pearl Cantabile, as an example. If you want to get that model with a C# trill, it will cost you over $600 more. Some brands, such as Burkart, charge close to $1,000 for the spec.
When you’re buying a flute, there are multiple ways to save money. One of those ways is to get a more basic model.
Heavier Weight
I’ve heard some players claim that a C# trill key adds too much weight to the flute and that it shifts the balance a bit. Unfortunately, I can’t compare that directly since I don’t have two flutes where the trill key is the only difference.
However, it’s worth considering if that’s true. It may be more noticeable to you than it is to me, even if I could test it.
If you’re already getting a flute with a heavy wall or that has some gold in it, that can also make it heavier. Adding a C# trill might just make it too heavy for you to hold comfortably.
Time to Get Used To
Like any new thing, it takes a bit of time to get used to the C# trill. You don’t have to worry as much about alternate fingerings or awkward trills.
But if you’ve played the flute for years, you might not have problems with those things. It could take a while to remember to use the C# trill when you’re able to use it.
Of course, once you do get used to it, playing will be much easier. You won’t have to think twice about the key.
Who Should Get a C# Trill Key?
Any serious flute player should at least consider getting the C# trill key on their next flute. Before I bought my pro model, I knew I wanted one.
That made it easier to search for flutes when it came time to buy. But if you’re more of a casual player, you can probably get by without it.
Can You Add a C# Trill Key to a Flute?
I haven’t heard of anyone adding a C# trill key to an existing flute. If you can do so, you’ll probably have to pay a lot of money.
A maker or tech will have to cut a hole in the flute to add the tone hole. They’ll also have to add the rod to make the spec work. So you could risk your flute not sounding as good if something goes wrong.
Can You Get a C# Trill Key on a Piccolo or Low Flute?
I’ve seen a couple of high-end piccolos with the option for a C# trill key. But it’s not very common to have one.
The same is true of low flutes, so you’d need a more expensive model. Also, if your alto flute has an ergonomic left-hand design, there may not be space for the C# trill tone hole due to where the thumb keys sit.
Will You Get a C# Trill Key?
A C# trill key is probably one of the best flute specs out there. If you’re looking for a new flute, consider getting the feature.
It can do a lot, and even if it does weigh a bit more, it’s worth it.
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