The terms HDMI ARC and optical audio cause a great deal of confusion among consumers. These two connections are similar in many ways, however, there are also differences between them. Many individuals are unsure as to whether or not these two connections may be used at the same time or not.
As a general guide, HDMI ARC and optical audio can be used concurrently. This, however, is subject to a number of variables. You can only use HDMI ARC and optical audio when connecting two devices, one of which does not support HDMI ARC.
As a result, in this case, optical audio could be used for sound transmission while HDMI ARC could be used for visual signal transfer.
However, if you are connecting devices that offer HDMI ARC support, you will not need the optical audio cable. If you happen to connect both the HDMI ARC and optical audio cable, your device (in this case your television) automatically disables the optical audio connections and therefore, all the transmissions will be carried through the HDMI ARC cable.
What is HDMI ARC and how does it work?
This is a feature of HDMI that facilitates the transmission of both audio and video signals over a single HDMI connection. This function was initially introduced in the HDMI 1.4 release. When utilizing HDMI connections, you have the benefit of being able to send both audio and video signals across devices using a single cable.
This, however, will only function if you are connecting devices that are capable of supporting HDMI ARC (Audio Return Channel). If one of the devices does not support HDMI ARC, it is not possible to use HDMI ARC in any other situation.
What precisely is an optical audio, and how does it work?
This technology operates in the same manner as HDMI ARC, and its objective is to transport audio signals between devices. A distinguishing factor between it and the HDMI ARC is that this can be used for the transmission of video signals.
Is there a difference in the audio quality between HDMI ARC and Optical Audio?
The audio quality transmitted through optical audio and HDMI ARC is the same. In other words, no matter what kind of cable you use, there will be no change in the overall quality of the audio.
Aside from that, both HDMI ARC and optical audio are incapable of sending audio data in codecs such as Dolby HD or the original 7.1 surround sound format.
Because HDMI ARC and optical audio can only transfer audio signals at 5.1 surround sound quality, transmitting audio formats such as 7.1 surround sound over HDMI ARC or optical audio will result in the sounds being downgraded to 5.1 surround sound quality, as explained above.
Newer versions of the ARC standard, on the other hand, are capable of transferring lossless audio files. This new standard, known as HDMI eARC, is only present in the majority of high-end products that are also the most expensive.
Conditions for using HDMI ARC and Optical Audio at the same time
To use HDMI ARC and Optical audio at the same time. Certain conditions must be met. The main condition is that between the two devices you are connecting, one should not support HDMI ARC. Why? If one supports HDMI ARC, connecting the two at the same time is impossible as your TV will keep switching to the input inserted last.
Conclusion
Although you can be able to connect HDMI ARC and optical cables at the same time. If you are using devices that support both optical cables and HDMI ARC, it means that your device will most likely use HDMI ARC for transmission and switch off the optical audio transmission completely whenever the HDMI ARC is connected.
The same is true if you attach optical audio while the HDMI ARC is connected; most devices will automatically switch the connection from HDMI ARC to optical audio.
As a result, it is critical to determine whether or not your device supports HDMI ARC, which can be determined by looking at the ports on the back.
When transmitting lossless audio formats, HDMI ARC cables and optical audio do not support them; thus, if you wish to transmit lossless audio formats, you should consider acquiring equipment that is compatible with eARC.