“Ok Google, why does your wake-up word work so well?” is a question we could ask directly to the voice assistant of this digital giant. However, it would be very difficult to obtain the answer from an artificial intelligence because of the complexity of this technology. This is where we come into action!
As a reminder, the Wake-Up Word, or Hot Word, is a brick, a module, of speech recognition in the global sense of the term. It is a word or a series of words that allows to trigger the voice recording of the user of a speech recognition system. Although, if we make a small retrospective of the news of Google we can realize that their assistants tend to listen a little more than what is expected.
This “keyword” such as the famous “Ok Google” is used to activate the system for two reasons:
- It respects the privacy of users so that only the sequence that follows the Wake-Up Word is recorded. This one corresponds to the intention, and it is then legitimate that the system records it.
- It optimizes system consumption and performance as constant recording and analysis of audio files is a very heavy task if performed continuously.
Now that the meaning of Wake Word is clear, let’s dive into the topic: knowing what makes a good one. Indeed, under its rather simplistic appearance and more of a brand image issue at first glance, it is a real puzzle to find THE right word.
In this sense, Google speech recognition displays a rather exemplary trigger word for several reasons.
Simplicity is key for a wake word
First good lesson from Google and this applies mainly to marketing! Indeed, their wake-up word takes the name of their brand which is added to a very common and simple word to say: “ok”. As a result, thousands of users, whether it’s the voice assistant or the connected speaker, keep repeating Google when they interact with the brand’s tools.
In terms of brand awareness, what could be better? Google’s name already is certainly one of the most reknown nowadays, we let you imagine the rest.
Yet, Amazon’s Alexa is also an example of a great wake word as they chose a humanoid name for their conversational AI. Indeed, a real name may help create a stronger relationship with the users. And, as they associate the conversational AI’s name to your brand, it strengthens their relationship with it too! This strategy can prove to be really effective, but you need to keep in mind that your brand should already be well established. Overwise, you should prefer to include your brand name in it, in order to remain top-of-mind thanks to your smart assistant. And if your brand IS a name? Well, who knows, maybe it is the best case scenario.
Choosing a uniform word
To this we can add a more pragmatic aspect very well managed by Google’s voice recognition. One of the strengths of its wake-up word is its uniformity. Whatever the languages, everybody says “ok” and “Google” in the same way. This is very practical for several reasons, but the main one is that only one wake-up word applies to all markets covered by Google! It seems harmless like that, yet it is very complicated to translate a Hot Word while maintaining consistency and efficiency. Speaking of efficiency, let’s continue on the third point!
Effectiveness at its best
To finish with these praises, Google has found a combination of words that is technically very effective in terms of voice recognition. Indeed, when imagining and developing a Wake Word it is very important to be aware of false positives. False positives are unexpected errors that send positive answers when in reality they are negative. Indeed, the phonemes are the smallest elements composing an audio frequency (translating sound). If a false positive occurs, it may be because phonemes are very close, following a mispronunciation for instance. From then on, the system can be activated and record the conversation without the users’ knowledge.
Thus, “Ok” and “Google” are composed of very different and distant phonemes. It results in a very low false-positive rate for Google’s speech recognition.
The rise of minimalism
OK Google, Hey Siri… conversational AIs usually use different words in addition to their brand name as wake words. In the search for better customer experience, it is clear that there are still some improvements to make. For instance, repeating “OK Google” or “Hey Siri” before each sentence to ask something to your smart assistant is irritating. That’s why Google and Apple are slowly giving up on their multiple wake up words.
The single word – wake word adopted by Apple’s Siri
Indeed, Apple recently announced that Siri won’t need to hear “Hey” before its name anymore. Indeed, the brand is trying to change its wake word so that it is more natural to interact with the conversational AI. Thus, simply calling “Siri” would work. But doing it may not be as simple as it seems. As we explained earlier in this post, wake words should be specific enough to be effective and noise-robust.
Before completely removing extra syllables from the formula, the brand needs to make sure that Siri is still able to understand when it has been called or not. As it also implies sending data to the Cloud, smart assistants aren’t *supposed* to be recording everything. Yet, it wouldn’t be the first to have only the name of the smart assistant as a wake word. Indeed, Alexa, the conversational AI from Amazon, has never needed an extra word.
Google’s choice for smoothing the conversation flow
Google also decided that the wake word was probably too long and not natural to speak up. Indeed, in 2018, they launched the “continued conversation”. It consists of saying the wake up word only once to activate the active listening and being able to pursue a conversation. The assistant would understand and respond to multiple voice commands without having to re-activate it. It makes the flow more natural and allows for more convenience and a better user experience.
Still, it is important to think about different wake words to make sure that the conversational AI responds to every request. For example, in addition to the branded one, smart home devices should recognize words such as “Help me” for instance. This would allow them to alert someone when an emergency occurs.
In this article, we have seen, through different examples, what makes a good Wake Word and the important aspects to take into account when choosing it. To learn more about the rest of voice technologies, other articles in our blog cover different topics related to this technology.