Have you ever wondered whether an Optical cable can support Dolby Digital Plus?
Well, you’re not alone. One question that often comes up is whether an Optical cable, also known as a Toslink or SPDIF, can pass Dolby Digital Plus to your home theatre or receiver.
I know that navigating the world of cables and connectors can be a bit of a headache, so I’m here to break it down for you in an easy yet precise way.
Whether you’re a tech novice or an audiophile, this article will give you a better understanding of the capabilities of Optical cables along with the limitations of Dolby Digital Plus.
As you might be aware the Dolby Digital Plus format is a digital audio standard that improves the sound quality of movies, TV shows, and other audio content. Let’s first understand how it usually transmits sound to different receivers.
How Do Dolby Digital and Dolby Digital Plus Transmit?
One way is through a high-bandwidth HDMI 1.4+ digital interface. This sends the bitstream signals directly to advanced digital A/V receivers with Dolby Digital Plus decoding. Pretty cool, right?
Another option is using analog outputs. This method involves decoding the multichannel Dolby Digital Plus signals inside the player and then sending them to a connected A/V receiver.
Lastly, Dolby Digital Plus signals can be decoded to PCM inside the player and then transported via HDMI 1.4+, and the latest HDMI 2.1, ARC, and eARC connections.
All in all, there are a few different ways to transport Dolby Digital Plus content to your home theatre, but it’s important to have the proper decoding equipment as well as compatible cable (HDMI 1.4+) to fully enjoy the enhanced audio.
Now coming to our main question whether Dolby Digital Plus can pass through Optical cables?
Does Optical Cable Support Dolby Digital Plus?
When it comes to transmitting Dolby Digital Plus via optical cables, such as TOSLINK or SPDIF, it is not possible.
TOSLINK is a type of optical cable that is commonly used in consumer equipment, such as home theatre systems.
It has a bit rate limit of about 3.1 megabits per second, which is sufficient for older audio formats such as Dolby Digital AC3 and DTS.
However, it is not enough for newer, lossless formats such as Dolby TrueHD and DTS HD Master Audio.
Dolby Digital Plus is also a lossless audio format that requires a higher bit rate than TOSLINK can provide. Additionally, Dolby has put a software block on anything that can carry Dolby ATMOS, which is a feature of Dolby Digital Plus, that restricts it to HDMI connections only. This means that it cannot be transmitted over TOSLINK or SPDIF.
In conclusion, TOSLINK and SPDIF do not support “Dolby Digital Plus”, and they can only be transmitted via HDMI connections. This is due to the high bit rate requirements of the format, as well as the software block that Dolby has put in place for Dolby ATMOS.
What types of audio can be enjoyed with optical and Dolby Digital Plus?
With an optical cable, you can enjoy a variety of audio formats such as:
- 2-channel PCM audio at a sample rate of 44.1 kHz and a bit depth of 16 bits, which is the standard for CDs.
- 2-channel audio at sample rates of 48 kHz and 24 bits. Some devices may even support sample rates of 96 kHz.
- Dolby Digital AC3 and the original DTS format which are lossy compression audio formats, they allow 5.1 channel audio to fit in the limited bit rate and can be sent over TOSLINK.
However, you cannot enjoy lossless 5.1 and 7.1 audio formats such as Dolby TrueHD and DTS HD Master Audio over TOSLINK as they require too much bandwidth.
Regarding Dolby Digital Plus, since it is a lossless audio format, it provides the highest quality audio experience. It supports up to 7.1 channels of audio and includes features such as Dolby Atmos and Dolby Surround, which provide a more immersive and realistic sound experience. To enjoy Dolby Digital Plus, a device with HDMI input and output and equipped with Dolby Digital Plus decoding is needed.
Difference Between Optical Cable, SPDIF, and Toslink?
- Optical Cable:
- It’s a cable that uses light to transmit data, commonly used for audio and video in home theaters and digital audio players.
- SPDIF (Sony/Philips Digital Interface Format):
- A digital audio interface that sends audio data between devices, it can be transmitted over optical or coaxial cables. Commonly used to connect digital audio devices.
- Toslink (Toshiba Link):
- It’s a specific type of optical cable that transmits SPDIF audio signals. Mostly used in consumer audio equipment like home theater systems, sound bars, and digital audio players. It has square connectors and is typically used to connect digital audio devices that have an optical input or output.
In simpler terms, an optical cable is a fancy cable that uses light to transmit audio and video, SPDIF is a way to send audio data between devices and TOSLINK is a type of optical cable that is commonly used in home theater systems and other consumers audio equipment to transmit audio data.
In short, Dolby Digital Plus is a high-quality audio format that requires HDMI connections to work properly. It can’t be transmitted via optical cables such as TOSLINK or SPDIF, as they have a lower bit rate limit that can’t handle Dolby Digital Plus’ data.
The software block put in place by Dolby for Dolby ATMOS, a feature of Dolby Digital Plus, also restricts it to HDMI connections only. So, if you want to enjoy the enhanced audio quality of Dolby Digital Plus, make sure your device has HDMI input/output and Dolby Digital Plus decoding.
Does optical pass Dolby Atmos?
No, optical does not pass Dolby Atmos. Dolby Atmos is a surround sound format that requires more bandwidth than optical can provide. To get the full effect of Dolby Atmos, you will need to use an HDMI connection or use a compatible soundbar with built-in support for it.
Is Dolby digital the same as Dolby digital plus?
Dolby Digital Plus is a more advanced version of Dolby Digital that includes additional channels and features that are not supported by older formats.
Is it necessary to have a device with Dolby Digital Plus decoding to enjoy the enhanced audio?
Yes, it is necessary to have a device with Dolby Digital Plus decoding to fully enjoy the enhanced audio quality of Dolby Digital Plus.
Can lossless audio formats such as Dolby True HD and DTS HD Master Audio be transmitted over TOSLINK?
No, lossless audio formats such as Dolby True HD and DTS HD Master Audio require too much bandwidth and will not work over TOSLINK.
What is the bit rate limit of TOSLINK?
The bit rate limit of TOSLINK is about 3.1 megabits per second.
What type of connector is required to transport Dolby Digital Plus content?
A high-bandwidth HDMI 1.3 digital interface is required to transport Dolby Digital Plus content.
What HDMI Is Best For Dolby Atmos?
Dolby Atmos requires an enhanced ARC (eARC) HDMI connection which provides a bandwidth of 37 Mbps, sufficient for transmitting as many as 32 channels.