How to customize Sparky's voice

This update was released February 20, 2026.

In this article, you will learn how you can customize Sparky's voice, both in tone and speed, for speaking activities.

Here is how to do it:

After reaching the Activity Builder, you have two ways to customize Sparky's voice:

You will now be at your activity dashboard page. You can find activity settings in the top right corner of your screen.

After clicking "Activity settings," you will be taken to the Activity Builder, where you can find both "Build with Sparky" and "Build manually."

Through "Build with Sparky," you can ask Sparky to make adjustments without having to manually adjust voice tone and speed. Note that Sparky can only adjust its voice if the activity is a speaking activity. Learn how to check if your Sparky is configured to speak in the activity.

You can easily message or use your mic to ask Sparky to adjust their voice. In this example, I just asked "Can Sparky speak in a masculine voice instead?"

Sparky then adjusted its voice from Harper (warm and friendly female voice) to Reid (clear and direct male voice). Learn more about what kinds of voices Sparky has available.

This is the same process as when you ask Sparky to sound more masculine or feminine. Simply message or use your mic to ask Sparky to adjust their speaking rate. In this example, I've asked Sparky to speak slower.

Sparky immediately adjusted their speaking rate to change from 1x to 0.875x. Learn more about Sparky's speaking rate.

After you are done customizing your activity, click "Update activity" to save changes.

Through "Build Manually," you can make more granular changes and choose exactly which voice and speaking rate you want for Sparky.

You can find "Language" in the lefthand sidebar.

You can only adjust Sparky's voice and speaking rate if Sparky's communication includes speaking. You can check this by going to "Sparky's communication." In this example, you'll see that Sparky is Speaking only.

You can choose between Speaking only, Writing and speaking (with autoplay), or Writing and speaking (without autoplay).

Go to "Sparky's voice," which you can find at the bottom of Language settings. Use the dropdown to choose how Sparky sounds when speaking. In this example, I've chosen Reid.

You can also preview how the voice sounds by clicking the play button to the right of the dropdown. Learn what kind of voices Sparky has.

At the very bottom of language settings, you can find the "Speaking rate" customization feature. You can adjust the slider based on how slow or fast you want Sparky to speak. In this example, Sparky is speaking at 0.875x speed, in between .75x and 1x.

Learn more about Sparky's speaking rate.

After you are done customizing your activity, click "Update activity" to save changes.

There are 5 female voices to choose from:

There are 4 male voices to choose from:

By default, Sparky will speak at 1x speed, which you can think of as the speaking pace in an average, casual conversation. You can speed up to 1.5x, and slow down to 0.5x.

If you ask Sparky to speak slower or faster through "Build with Sparky," Sparky will approximate how much to adjust itself. If, however, you would like more granular control over Sparky's speaking rate (for example, knowing you want Sparky to speak at 0.875% speed), it may be better to go into "Build Manually" to adjust.