Apple has released the third developer beta of iOS 27, and the standout feature isn’t a flashy UI overhaul or a deep AI integration—it’s a pair of deceptively simple sliders that let you control how Siri speaks. The new Pace and Expressivity controls, nestled in the Siri settings, allow users to adjust the speed and emotional inflection of the assistant’s voice. For anyone who’s ever wished Siri would speed up during a recipe or sound more empathetic when delivering bad weather news, this is a small but meaningful update.

Siri Gets a Voice Tuning Kit

In iOS 27 Developer Beta 3, Apple added two new customization options for Siri’s voice feedback: Pace and Expressivity. The Pace slider lets you slow down or speed up Siri’s speech, while Expressivity adjusts the level of emotion—such as pitch variation and emphasis—in the synthetic voice. Both controls appear under Settings > Siri & Search > Siri Voice, alongside the existing voice selection and the option to download high-quality neural voices.

Early testers report that the changes are immediately noticeable. Cranking up Expressivity makes Siri sound almost conversational, with natural rises and falls, while dialing it down flattens the tone to the more robotic delivery of earlier Siri iterations. The Pace control does exactly what you’d expect: at its fastest, Siri zips through responses; at its slowest, it enunciates with deliberate clarity. These controls work with all Siri voice options—male or female, accent or language—provided you have the latest neural text-to-speech files downloaded.

What It Means for You

Everyday users. If you use Siri regularly—whether on an iPhone, iPad, or HomePod—you can now tailor the assistant’s speaking style to your liking. Speed it up for quick time checks or weather updates; slow it down when you need to follow along with a step-by-step guide. Add expressivity to make interactions feel less sterile, or reduce it if you prefer a straight-to-the-point assistant. For those who rely on Siri for accessibility, such as users with visual impairments or cognitive disabilities, the ability to fine-tune speech output can make a substantial difference in comprehension and comfort. Picture yourself driving and needing navigation prompts: a faster, more expressive Siri could relay directions without distracting you, while a slower pace might help when you’re parked and reviewing a grocery list.

Power users and developers. These controls hint at a larger push toward adaptable AI interfaces. With Apple Intelligence on the horizon, giving users granular control over how AI communicates could pave the way for more natural human-AI interaction. Developers testing beta 3 can experiment with the new Siri responses in their apps and provide feedback to Apple via the Feedback Assistant app. If Apple eventually exposes these controls via Shortcuts or APIs, developers could craft customized voice experiences—for example, a meditation app that offers a calm, slow Siri voice, or a fitness app that uses an energetic, fast-paced one.

IT professionals. For organizations managing fleets of Apple devices, the ability to standardize Siri’s voice parameters could improve user satisfaction and accessibility. While Apple hasn’t announced enterprise configuration profiles for these settings, the existence of the controls suggests it’s a possibility. This would be akin to how Microsoft allows IT admins to set default speech settings in Windows via Group Policy or MDM. Imagine a healthcare setting where nurses use iPads with Siri set to a clear, moderate pace and neutral expressivity to avoid miscommunication during critical tasks.

The competitive landscape. Amazon Alexa has long offered a speed control mode, and Google Assistant includes speech rate adjustments in its accessibility settings. However, the Expressivity control is a novel twist. Apple’s focus on emotional inflection sets it apart, and if executed well, could make Siri feel more like a human assistant than a query machine. For Windows users who have watched Cortana’s voice assistant ambitions fade, this is a reminder that Apple still believes in an audible digital assistant as a primary interface—and it’s a challenge to Microsoft’s Copilot to evolve beyond text-based interactions.

How We Got Here

Siri’s voice has evolved dramatically since the assistant’s debut on the iPhone 4S in 2011. Early versions used concatenative synthesis, piecing together pre-recorded snippets, which often sounded choppy and unnatural. In iOS 13 (2019), Apple introduced neural text-to-speech (TTS), which used machine learning to generate more natural speech on the fly. That update also brought the option to choose between male and female voices in various accents. The underlying technology, similar to Amazon Polly or Microsoft Azure Text to Speech, relies on deep learning models trained on thousands of hours of recorded speech to predict and generate waveforms that sound human.

iOS 16 (2022) introduced more expressive prosody for certain Siri responses, such as when telling a joke or delivering news. But until now, users had no control over the emotional delivery. The arrival of Pace and Expressivity sliders in iOS 27 beta 3 aligns with Apple’s broader push into AI. The company is expected to unveil major Apple Intelligence features alongside new iPhones this fall, and these sliders might be laying the groundwork for a voice assistant that can dynamically adapt its tone based on context—something Google’s Duplex technology attempted with human-like reservations.

The beta timeline is predictable: Apple released iOS 27 developer beta 1 in early June, following the Worldwide Developers Conference. Beta 2 arrived two weeks later, and beta 3 just landed. Typically, we’ll see beta 4 through 8 before the public release in September. A public beta for non-developers usually ships alongside developer beta 3 or 4, so it’s imminent.

What to Do Now

If you’re a developer: Download the beta profile from the Apple Developer Program, install it on a test device, and head to Settings > Siri & Search > Siri Voice. Experiment with both sliders and note any bugs or unexpected behavior. Use the Feedback Assistant app to report your findings—Apple pays close attention to developer feedback during the beta cycle, and your input could shape the final release. Be mindful that beta software can be unstable, so avoid using it on devices you rely on daily.

If you’re an enthusiast: Wait for the public beta, which should be available soon. Avoid installing developer betas on your primary device; they can contain significant bugs, battery drain, and app incompatibilities. When the public beta arrives, you can enroll at beta.apple.com and install it on a secondary iPhone if you have one. If you’re eager to try it now, consider creating a secondary Apple ID for testing to keep your main account safe.

If you’re a typical user: No action is needed. The feature will come to you this fall as part of the free iOS 27 update. When it does, simply go to the Siri Voice settings and tweak the sliders. There’s no rush, and you’ll benefit from the refinements made during the beta period.

Security note: This beta does not introduce any known security fixes beyond what’s already in beta 2, but as always, running beta software may expose your device to unpatched vulnerabilities. Stick to stable releases unless you accept those risks.

Outlook

The Pace and Expressivity controls are just the beginning. As Apple Intelligence matures, expect Siri to gain even more nuanced voice capabilities—perhaps the ability to whisper, shout, or use different emotional registers for different contexts. A future beta might let Siri automatically adjust its speed based on your speaking pace, or sound more sympathetic when it knows you’re discussing a sensitive topic based on on-device intelligence. These controls could also sync across your Apple devices via iCloud, so your Siri sounds consistent whether you’re on an iPhone, iPad, or HomePod.

For Windows users who rely on cross-platform Apple services like iCloud, Apple Music, or iTunes for Windows, these Siri improvements could eventually influence how those services’ voice interactions are designed, although Siri itself remains unavailable on Windows. Microsoft, meanwhile, has shifted its AI voice focus to Copilot, which currently lacks the same level of user-facing voice customization. Apple’s move could spur a new wave of voice personalization across the industry.

Watch for iOS 27 beta 4 in about two weeks. We’ll be testing the new Siri controls thoroughly and reporting back on whether they live up to the promise. In the meantime, if you get your hands on the beta, let us know in the comments how you’re tuning your Siri.