Soundbars typically come with numerous options to connect your media devices and TV’s. It is important to understand which connections are crucial to enjoying the best home theater performance.
i. HDMI inputs, ARC vs eARC
Good soundbars are built to receive audio via HDMI - the same connection used by today’s media devices (e.g. 4K streaming sticks) to send video. When such devices are connected directly to a soundbar’s HDMI inputs, the soundbar receives high quality audio directly - before sending video information up to the TV. This function is also known as video passthrough.
What is HDMI eARC and ARC?
ARC stands for Audio Return Channel. HDMI ARC allows TVs to send audio signals from its streaming apps (or devices connected to it) to the soundbar. HDMI ARC allows the TV to send compressed surround sound (Dolby Digital + with Dolby Atmos) to the soundbar. This format is used by mainstream streaming platforms to deliver surround sound.
eARC stands for “enhanced Audio Return Channel”. Think of it as a higher bandwidth, newer revision of ARC. When the TV/Projector and soundbar both support eARC, you can enjoy full quality audio (i.e. Dolby TrueHD with Atmos, or DTS:X) from your soundbar, even if gaming or streaming devices are connected to your TV. Thus, having eARC support in your next soundbar or TV is a big plus point.
The following chart summarizes the capabilities of ARC vs eARC:
| Audio Return Channel | Enhanced Audio Return Channel | ||
|---|---|---|---|
| ARC - Single Mode | ARC - Common Mode | eARC | |
| Rating | Good | Better | Best |
| Introduced In | HDMI 1.4 (2009) | HDMI 1.4a (2010) | HDMI 2.1 (2017) |
| Max Bandwidth | 1Mbps | 6 Mbps | 37 Mbps |
| Audio codecs and formats supported | Baseline
|
Higher Quality Surround
|
Full Quality (Lossless) Audio
|
| Example types of content |
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| Available in |
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Apart from higher audio quality, soundbars with eARC are more stable, as the connection protocol (also known as a handshake) is improved. In addition, eARC also has automatic lip sync correction.
ii. HDMI vs Optical/Coaxial inputs
Optical and coaxial are considered legacy (older) connections. These connections can only support compressed surround sound formats without Dolby Atmos.
Thus, having optical and coaxial connections ensures compatibility with older devices. However, it is no longer the best method to connect a modern 4K TV to the soundbar.
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| TYPES | HDMI Inputs | OPTICAL/COAXIAL |
|---|---|---|
| Stereo: Dolby & DTS & PCM |
✅ | ✅ |
| Compressed 5.1: Dolby Digital & DTS |
✅ | ✅ |
| Uncompressed 5.1: Dolby Digital Plus & DTS-HD & Multichannel PCM |
✅ | ❌ |
| Uncompressed 7.1: Dolby TrueHD & DTS-HD Master Audio |
✅ | ❌ |
| Object-based Audio: Dolby Atmos & DTS:X |
✅ | ❌ |
| Link Discovery: Volume Control/Mute, Power Control |
✅ (CEC) |
❌ |
|
2-Way Transmission (Video and Audio) |
✅ (ARC / eARC) |
❌ |
ii. Bluetooth vs WiFi
Source: Samsung website
With at least Bluetooth connectivity found in all soundbars today, they can indeed perform well as living room speakers. Commonly, they are paired with mobile devices to play stereo content from platforms such as Spotify, YouTube and iTunes. Some soundbars also support higher bandwidth codec such as AptX, AptX-HD, AAC and LDAC, allowing the transfer of high-quality audio wirelessly via Bluetooth.
WiFi connectivity is becoming increasingly popular in soundbars. As compared to Bluetooth, it allows devices to communicate with the soundbar within the same network, such that it is possible to stream music from anywhere at home instead of being constrained to the 33ft maximum distance from the soundbar (in Bluetooth). It also provides quicker access to online audio streaming services such as Spotify, Pandora and Tidal, online video streaming services such as Netflix, Amazon Prime and Google Chromecast, as well as the user’s personal network-connected library.
iii. 4K Compatibility
4K Ultra High Definition (UHD) is the high-resolution video standard that is rapidly being adopted by major streaming services, including Netflix, Amazon Prime and Apple TV. Therefore, it is essential to have 4K compatibility on your soundbar, so that the high-definition video can be passed through to your TV. There are also hardware requirements for soundbars to send and receive 4K content, namely HDMI 2.0 and HDCP2.2 standards, so it is important to look out for them when buying a soundbar.
| TYPES | HDMI 2.0 | HDMI 1.4 |
|---|---|---|
| Description | Connection standard for 4K/60fps video devices with higher bandwidth and HDR | Connection standard for 4K video devices with lower bandwidth |
| Key Spec |
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| Connector | HDMI | HDMI |
| Hardware | 4K UHD TV, 4K UHD Blu-ray Player, 4K Streaming Devices, Gaming Consoles | 4K TV, Blu-ray Player, Streaming Devices, Gaming Consoles |
| TYPES | HDCP 2.2 | HDCP 2.1/2.0/1.4 |
|---|---|---|
| Description | Content protection to prevent making illegal copy of 4K UHD video | Content protection to prevent making illegal copy of HD video |
| Key Spec |
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| Connector | HDMI, DVI, DisplayPort, USB, Wireless (WiFi) | HDMI, DVI, DisplayPort |
| Hardware | 4K UHD TV, 4K UHD Blu-ray Player, 4K Streaming Devices, Gaming Consoles | HD TV, Blu-ray Player, Streaming Devices, Gaming Consoles |
iv. 4K HDR Standards
There are multiple HDR standards available along with 4K UHD content to provide lifelike picture quality with dynamic contrast, high brightness and vibrant color. Streaming services such as Netflix and Apple TV are increasing the number of 4K HDR contents available for viewing.
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| TYPES | DOLBY VISION | HDR10+ / HDR10+ Adaptive |
HDR10 | HDR | HYBRID-LOG GAMMA |
|---|---|---|---|---|---|
| Description | Dolby version of HDR that is encoded scene by scene or frame by frame | Scene by scene approach based on HDR10 technique | HDR with average brightness range throughout the entire content | High Dynamic Range with wide color gamut with lifelike bright- ness and contrast levels | HDR format designed for cable, satellite and TV broadcasts |
| Key Spec | Brightness levels present at a given reference frame or scene rather than limited value for the entire film | Brightest point vs darkest point in
a video content is determined based on scene by scene. |
Brightest point vs darkest point in a video content is determined and fixed for the entire video | Equal clarity and brightness levels in between very bright and darker elements in the same frame | Designed for OTA broadcast with backward compatibility for SDR TVs |
| Content | Online streaming contents (Netflix, Amazon Prime Video, and Vudu), 4K Blu-ray Disc | Compatible with HDR10/HDR contents | Online streaming (Netflix), Compatible with HDR contents | Online streaming (Netflix and Apple TV), Blu-ray Disc, Console Gaming | NHK (Japan), BBC (UK) |
| Creator | Dolby | Samsung, Panasonic, Fox | Open Standard | Open Standard | NHK,BBC |
*HDR10+ (Adaptive) is a new processing technique available on compatible TV's, where the TV automatically optimizes the brightness of scenes further, based on your room lighting. Soundbars that support HDR10+ will support HDR10+ Adaptive.