Choosing a Wake Word
This document is intended for product owners who want to choose a wake word for their voice-enabled product.
Wake work is a special word or phrase that is meant to activate a given device via voice. It is also referred to as hotword, trigger word, and wake up word. There are a few well-known wake phrases that we use on a daily basis such as "OK Google", "Alexa", "Hey Siri", and "Cortana". This writing provides guidelines for choosing a wake phrase that boosts the accuracy of the product while serving your marketing and product requirements.
In this article, we make a distinction between wake words and voice commands. Wake phrases are listened to at all times whereas the voice commands are only listened to when the wake word is detected and for a brief time duraton. Guidelines for choosing voice commands are provided in this article.
A wake word needs to be unique and promoting its brand. Furthermore a good choice of wake word can substantially increase the accuracy of the voice interface it is enabling. Below are guidelines we gathered through numerious interactions with clients onboarding Picovoice's wake word engine.
1 - Avoid Short Single Words
Detecting short phrases is hard for both humans and machines especially in presence of noise and echo. Almost all of the well-known wake words have at least six phonemes. For example "OK Google" has eight phonemes and "Alexa" has six. Hence, choosing a wake phrase with less than six phonemes is not recommended. If your wake word has less than six phonemes you might want to choose a different one or a derivation of it. Alternatively, you can prepend it with "Hey", "OK", etc.
2 - Avoid Long Phrases
There is a trend to use shorter wake phrases. For example, Amazon has only single-word wake phrases and Google moved from "Ok Google Now" to "Ok Google". Long and multi-word wake phrases are cumbersome and can result in poor user experience.
3 - Choose Words with Diverse Sounds
Pick a phrase that has a variety of different sounds. A simple test for this property is to count the number of syllables in the wake phrase. For example, Alexa and Cortana both have three syllables. Choosing a wake phrase that has less than three syllables is not recommended. If your wake phrase has less than three syllables you may choose a different one or prepend it with "OK", "Hey", etc. For example "Google" has two syllables but "OK Google" has four.