As we get the Dio Node into full production gear, I thought I’d take a moment to demystify how exactly wireless speakers are made. I myself had no specific background in wireless speakers when I set out to create Dio Node, so today I’d love to dive in to everything I’ve learned about building the perfect speaker.
It all starts with a driver
No, I’m not talking about your DoorDash here, but a very different and innovative kind of driver. Whether you’re buying Bluetooth, Wi-Fi, or plain-old wired speakers, the one thing you always need is the speaker driver itself: the thing that actually converts electronic signals into physical sound that your ears can comprehend. Speaker drivers can come in all sorts of materials and sizes, but they are all essentially a cone that moves back and forth based on electrical signals. This motion creates air pressure at different frequencies. And that air pressure is – you guess it – sound waves! Of course, each speaker driver has a limit of what frequencies of sound waves it can produce, and that has led to classifying speakers in 3 different categories. (1) Woofers: these are drivers that can only play bass frequencies, (2) Mid-Range: these are the most popular kind of driver for their ability to play the higher end of bass frequencies and the lower end of treble frequencies, (3) and Tweeters: these are people who send messages in 280 characters or less, but are also speaker drivers that can only play treble frequencies.
While you can theoretically hardwire a speaker driver directly to an analog sound input, the most useful speakers have wireless sound transmission. The most popular form of this is Bluetooth, which sends your audio directly from one device (e.g, a phone) to your speaker. In order to receive this kind of wireless audio signal, a speaker needs two more things. First, it needs an antenna to receive this signal. Second, it needs a small processor to convert this signal into something the speaker driver can understand. The price of these components have gotten very cheap over time, which is why Bluetooth speakers can be as cheap as $10 on Amazon! Part of the reason for this is because Bluetooth forces your device to compress its audio file before sending it wirelessly, which means the audio loses data but also means you can use a less powerful processor in the speaker to “uncompress” the file.
Better audio, more computing
Dio Node, however, does not use Bluetooth. This is partly because Bluetooth is unable to offer the robust multi-speaker solution we do, but also partly because Bluetooth’s audio file compression means worse sound quality. To combat this, we instead use Wi-Fi to transmit your phone’s audio to your speakers. And no, I do not mean creating a speaker that connects to the internet to stream directly from Spotify the way Google Home and Amazon Echo do. Instead, Dio Node still transmits from your phone but using a much wider and more powerful radio band than Bluetooth. This band is Wi-Fi, and it ensures no sound quality is lost in transmission to your speaker. In order to receive this, the speaker still uses the same antenna, but needs a slightly better processor to handle converting the Wi-Fi data into actual sound for your driver. This is the last piece of the puzzle in how Dio Node is made!
And that’s it! Just 3 simple things – an antenna, a processor, and a speaker driver – are all that’s needed to create a fully functional speaker! Of course, there is a lot more you can add to make your speaker more than a speaker. For example, smart home speakers often include multiple antenna to send and receive multiple wireless signals across your home and the internet, voice assistant speakers include microphone arrays, and premium speakers include combinations of woofers, tweeters, and mid-range drivers in a particular balance. But here at Dio, we don’t force you to buy anything extra in our product. We just keep it simple with an antenna, a processor, and a speaker driver.