If you’re building a home theater setup or if you’re a music aficionado, then you know how vital high-quality audio is. And years ago, if you had a receiver that could handle optical audio inputs – you were the envy of all of your friends. It was the highest-quality home audio setup you could have.
But today, optical audio is much less common than it used to be. You’re far more likely to encounter equipment that relies on Bluetooth to transmit audio and connect components together.
And while Bluetooth offers the convenience of wireless connectivity, it does so while sacrificing some of the fidelity you’d get from an optical connection. But those aren’t the only differences.
To explain, here’s how optical audio stacks up against Bluetooth. We’ll cover their strengths, weaknesses, and some of the most frequently asked questions about each. Let’s dive in.
All About Optical Audio
As its name implies, optical audio refers to a system that transmits audio signals by converting them to pulses of light and passing them through a fiber-optic cable. It’s similar to systems that use the same technology to transmit data over the internet today. But it’s been around far longer. Here’s everything you need to know about optical audio.
What is it?
Optical audio makes use of cables made from plastic, glass, or silica to transmit audio between devices. It’s an old technology, having made its debut way back in 1983 when Toshiba began using it as the standard connector on its earliest compact disc (CD) players.
At the time, it was the only standard capable of passing nearly lossless audio from CDs to receivers and other audio equipment. If you own a device that has an optical audio input or output, you’ll recognize its unique appearance – which many people have likened to a tiny doggy door.
The Pros and Cons of Optical Audio
Optical audio connections were designed from the ground up to provide a near-lossless method of transmitting audio. And they do so very well.
The standard can transmit up to two channels of 48kHz, 16-bit uncompressed audio. With a maximum cable distance of 10 meters, it’s still one of the go-to audio standards on modern televisions and stereo equipment.
But it’s based on old technology, so there are some limitations. It can’t handle newer audio standards like Dolby Atmos or DTS:X. And, on most of the devices that still include it as an option, it’s more of a fallback when you can’t use an HDMI cable, like when you connect your TV straight to a soundbar.
Features and Cost of Optical Audio
Optical audio connections are still useful, despite their age. You might use them to connect a CD player to your home stereo system, or your television to your soundbar or home theater receiver. It can handle an audio bandwidth of around 384 Kbps, which is perfect for non-surround sound applications.
And the cables you need to use it are quite inexpensive. For around $15, you can purchase a 10-foot high-quality optical audio cable to link your audio equipment together.
All About Bluetooth Audio
Launched more than a decade after optical audio hit the market, Bluetooth is a wireless audio and data transmission technology that’s become standard on many of today’s audio and video devices.
And while it’s not directly comparable to optical audio, the two are often found in the same device, leading to questions about which to use when. Here’s everything you need to know about Bluetooth.
What is it?
Bluetooth is a short-range data and audio transmission technology designed by cellular phone manufacturer Ericsson back in the late 1990s. It was initially built as a means of connecting devices together without wires over short distances.
Today, it’s built into every smartphone on the market, as well as a variety of consumer-grade audio and video equipment. If you own a wireless speaker or phone headset built in the last two decades, it most likely relies on Bluetooth technology.
The Pros and Cons of Bluetooth
The most obvious advantage of Bluetooth technology is that it’s wireless. This means you can use it to link together audio players and speakers to create an instant home theater or music-lover’s paradise. But it’s not strictly an audio-focused technology.
You can also transmit data over Bluetooth, which is why you’ll also find it networking together smartwatches and smartphones, and powering many of the latest IoT devices.
As far as audio is concerned, though, Bluetooth is far more limited than optical cabling. The main audio standard used by Bluetooth devices is called the Advanced Audio Distribution Profile (A2DP). It allows for 48kHz compressed audio at a maximum of 345 Kbps.
But the compression it relies on isn’t particularly good. It represents a significant quality loss compared to other standard compression formats like MP3, AAC, and Vorbis. And although a newer codec, called aptX, improves on that, it’s still not as common in today’s devices.
Features and Cost of Bluetooth
Bluetooth excels when it comes to features, availability, and cost. If you own a recent smartphone, stereo, or any other consumer electronic item, there’s a good chance it has Bluetooth built-in. And hundreds of manufacturers make accessories that use it.
That means you can find low-end Bluetooth speakers for as little as $10, and high-end ones for as much as $350 or more. And because Bluetooth’s so ubiquitous, it should remain well-supported for some time to come.
Frequently Asked Questions
Both optical audio and Bluetooth have so many uses that people have plenty of questions about them. Here are a few answers to the most common ones.
Is there any reason to still use optical audio?
If you have two devices that offer optical audio as an option, and they don’t transmit any of today’s high-end surround-sound standards, then yes. Optical audio is a great option, particularly where HDMI is unavailable.
Can you extend the range of optical audio?
One of the limitations that makes optical audio impractical is its 10-meter maximum cable range. But you can purchase adapters that use Ethernet to extend its range up to 300 meters.
Is Bluetooth affected by WiFi signals?
Although Bluetooth shares the same frequencies as some WiFi standards, it (and they) has features meant to avoid interfering with each other. Therefore, it’s normally not a problem except in high-density, noisy wireless environments.
Is Bluetooth secure?
For most purposes, Bluetooth connections are secure. Because it has such a short transmission range, it would be difficult for anyone to eavesdrop on it. But many devices use insecure pairing PINs (like 0000) that could allow an unauthorized person to connect to a broadcasting device.
But keeping Bluetooth radios powered off when not in use can guard against that.