HDMI ARC is better than optical audio for modern setups — it supports Dolby Atmos, DTS HD Master Audio, and up to 7.1 surround sound, while optical is limited to compressed 5.1 formats. Use optical only if your device lacks HDMI ports or you have legacy equipment.
- Both TV and audio device support HDMI ARC or eARC
- You want lossless audio formats like Dolby Atmos or TrueHD
- You prefer a single cable for audio and control signals
- You need surround sound beyond 5.1 channels
- Your soundbar or receiver has no HDMI ports
- Your cable run exceeds 50 feet (optical handles longer distances)
- You are using older equipment without HDMI ARC support
- Budget is tight and a cheaper optical cable is sufficient
What Is the Difference Between HDMI ARC and Optical?
HDMI ARC (Audio Return Channel) carries audio over the same HDMI cable already connecting your TV to a soundbar or receiver. Optical (TOSLINK) uses a dedicated fiber cable that transmits audio as light pulses. Both send digital audio — but what they can carry is very different.
HDMI ARC provides up to 1 Mbps of bandwidth. Optical tops out at 384 Kbps. That bandwidth gap is why optical cannot support modern lossless audio formats.
Audio Format and Channel Comparison
| Setup | Works? | Need | Note |
|---|---|---|---|
| Dolby Atmos via HDMI ARC | Yes | eARC port on TV | Requires HDMI 2.0 or later |
| Dolby Atmos via Optical | No | — | Optical bandwidth too low |
| Dolby Digital 5.1 via Optical | Yes | TOSLINK cable | Compressed format only |
| DTS HD Master Audio via HDMI ARC | Yes | eARC port | Lossless, full quality |
| PCM Stereo via Optical | Yes | TOSLINK cable | Basic stereo only |
When to Choose HDMI ARC
If your TV and soundbar both have an HDMI ARC or eARC port, use it. You get better audio quality, fewer cables, and CEC control so one remote can manage volume. This is the right choice for anyone using a modern Blu-ray player, streaming stick, or home theater receiver.
If you are already connecting devices with HDMI, check out whether USB-C can connect to HDMI for mixed-device setups where port types vary.
When Optical Still Makes Sense
- Your soundbar or AV receiver has no HDMI input
- You need a cable run longer than 50 feet
- You are connecting older equipment from the early 2000s
- You are only streaming stereo or basic Dolby Digital content
Optical is also immune to electromagnetic interference, which matters in some commercial or industrial environments. For a standard living room, this is rarely a concern.
If you run into connection problems with any HDMI setup, see why USB-C to HDMI stops working for troubleshooting steps that apply to HDMI signal issues broadly.
For a deeper look at how audio formats are defined by standards bodies, the HDMI Forum’s ARC specification page explains the technical requirements in detail.
Bottom line: For any modern TV and soundbar pairing, HDMI ARC is the better choice — it delivers higher quality audio, supports current formats like Dolby Atmos, and reduces cable clutter. Stick with optical only when your hardware forces you to.