Connecting a soundbar to your TV is one of the most effective ways to upgrade your home entertainment system. But even the best soundbar will underperform without a reliable digital audio cable. The cable you choose determines whether you get crisp, immersive audio or suffer from dropouts, lag, or interference. With optical, HDMI, coaxial, and USB options available, understanding the strengths and limitations of each type helps you make a smart investment.

This guide examines the most popular digital audio cables for connecting soundbars to TVs, reviews top products, and provides practical tips for selecting and installing the right cable for your setup. Whether you're setting up a basic bedroom system or a high-end home theater, the right cable makes all the difference.

Types of Digital Audio Cables

Digital audio cables transmit sound as binary data, preserving signal integrity far better than analog cables. The four main types used with soundbars each have unique characteristics.

Optical cables use pulses of light to transmit audio through fiber optic strands. Because they don't conduct electricity, they are completely immune to electromagnetic interference from nearby power cables, routers, or other electronics. This makes optical cables a reliable choice for clean, noise-free audio. They support uncompressed stereo and compressed 5.1 surround sound formats like Dolby Digital and DTS. However, they cannot carry high-bandwidth formats such as Dolby TrueHD or DTS-HD Master Audio, which are common on Blu-rays. Most modern TVs and soundbars include an optical port, making TOSLINK one of the most universally compatible options.

HDMI (ARC and eARC)

HDMI cables are the most versatile solution because they carry both audio and video signals. For soundbar connections, the key feature is Audio Return Channel (ARC) and its enhanced version, eARC. HDMI ARC lets audio flow from the TV to the soundbar through the same cable used for video, eliminating the need for a separate audio cable. eARC, introduced with HDMI 2.1, supports higher bandwidth audio formats such as Dolby Atmos, DTS:X, and uncompressed 7.1 surround sound. If your TV and soundbar both support eARC, you get the best possible audio quality. Standard HDMI ARC is still excellent for most streaming and broadcast content. Look for cables labeled "High Speed HDMI with Ethernet" for ARC and "Ultra High Speed HDMI" for eARC and HDMI 2.1 features.

Digital Coaxial Cables

Coaxial cables transmit digital audio using electrical signals over a shielded copper core. They are similar to analog RCA cables but are designed for digital signals and have a characteristic impedance of 75 ohms. Coaxial cables can carry the same compressed 5.1 formats as optical cables but often deliver slightly better timing, making them a favorite among audiophiles for stereo music. They are also more durable than optical cables because they use metal connectors rather than fragile plastic. Many older TVs and soundbars still offer coaxial inputs, and the cable can run longer distances without signal degradation. However, coaxial cables are susceptible to electromagnetic interference if not properly shielded.

USB Cables

USB connections for soundbars are less common but appear on some models that support audio over USB. Typically, a USB cable connects the soundbar to the TV for power or data, but it only works as an audio path if both devices explicitly support USB Audio Class (UAC). Most TVs don't output audio via USB, so this is usually not the primary connection method. If your soundbar has a USB input for playing music directly from a flash drive, that is a different function. For connecting a soundbar to a TV, stick with optical, HDMI, or coaxial.

Best Digital Audio Cables for Soundbars

Choosing among hundreds of cables can be overwhelming. Below are reliable options for each cable type, based on build quality, performance, and value.

Top Optical Cables

AmazonBasics Digital Optical Audio Cable offers a solid, affordable choice with gold-plated connectors and a PVC jacket. It's available in lengths from 3 to 10 feet and supports standard optical audio formats. For a premium upgrade, KabelDirekt Optical Audio Cable features a braided exterior, aluminum housing, and polished optical termini for reduced signal loss. Both work well for most soundbar setups.

If you need a longer run, Monoprice Premium Optical Audio Cable comes in lengths up to 30 feet with reinforced connectors. For a rugged option, FosPower Digital Optical Audio Cable uses a zinc alloy shell and nylon braiding, making it more durable in tight spaces behind furniture.

Top HDMI Cables

For standard ARC setups, AudioQuest Forest 48 HDMI Cable is a well-regarded choice. It supports 48Gbps bandwidth for HDMI 2.1 features, including eARC, and has gold-plated connectors with solid conductors. For a budget-friendly alternative, Monoprice Ultra High Speed HDMI Cable is certified for HDMI 2.1 and eARC, offering excellent performance at a low price. It comes in lengths from 3 to 10 feet.

If you plan to upgrade to eARC-capable equipment, look for Belkin Ultra High Speed HDMI 2.1 Cable. It's certified for 48Gbps and supports all advanced audio formats. For short connections where flexibility matters, Zeskit Maya 8K HDMI Cable is slim yet certified up to 48Gbps, ideal for tight spaces behind a TV mount.

Top Coaxial Cables

For coaxial digital audio, Mediabridge Digital Coaxial Audio Cable is a popular choice. It features dual shielding, gold-plated RCA connectors, and a 75-ohm impedance rating. Available in lengths from 3 to 12 feet, it maintains signal integrity well. Monoprice Digital Coaxial Audio Cable offers similar specs at a lower price, with copper-clad aluminum conductors and corrosion-resistant connectors.

For longer distances, AudioQuest Cinnamon Digital Coaxial Cable uses silver-plated conductors and multiple layers of shielding. It's more expensive but can preserve signal quality over 20 feet or more. If you prioritize durability, AmazonBasics Digital Coaxial Audio Cable provides a balanced blend of price and performance for typical living room setups.

How to Choose the Right Cable for Your Setup

Selecting the best cable depends on your specific devices, audio preferences, and physical layout. Follow these guidelines to narrow down your options.

Check Compatibility

Start by examining the ports on your TV and soundbar. Look for HDMI ARC or eARC labeled ports (usually marked on the back). If both devices have HDMI ARC, that's your best option for simplicity and audio quality. If neither has HDMI ARC, use optical or coaxial. Many soundbars include both optical and HDMI inputs, while older TVs may only have optical. If your soundbar lacks HDMI, optical is the natural choice. USB audio is rare, so ignore it unless both manuals specifically mention USB audio support.

Consider Audio Formats

Think about what content you watch. Streaming services like Netflix and Disney+ typically use Dolby Digital Plus, which works over optical or HDMI ARC. Blu-rays and some streaming titles offer Dolby Atmos or DTS:X. To enjoy these object-based formats, you need eARC capability on both the TV and soundbar, plus an Ultra High Speed HDMI cable. Optical and coaxial cannot carry these high-bandwidth formats. If you don't own a Blu-ray player or often stream music in stereo, optical or coaxial is sufficient.

Cable Length and Quality

Measure the distance between your TV and soundbar. Add a few extra feet for flexibility. Optical cables are fragile and can be damaged if bent sharply. Keep bends gentle and avoid running them near power cables. Coaxial cables are more robust and can tolerate longer runs, but keep them under 20 feet to avoid signal loss. HDMI cables are sensitive to length: standard passive HDMI cables work reliably up to about 15 feet for 4K signals, and up to 25 feet for 1080p. For longer runs, use an active optical HDMI cable (which includes a fiber optic core) or an HDMI extender. Signal quality matters more with greater length, so invest in a well-shielded cable if your setup requires a long run.

Budget vs. Performance

You don't need a $100 HDMI cable for a basic soundbar. Digital cables transmit ones and zeroes, so any properly constructed cable meeting the required specifications will work. That said, cheap cables can have poor shielding, weak connectors, or substandard materials that cause random dropouts or signal loss—especially at longer lengths. Aim for mid-range options from reputable brands like Monoprice, AmazonBasics, KabelDirekt, or Mediabridge. Spending extra on gold-plated connectors and double shielding provides peace of mind and better longevity. For eARC and HDMI 2.1, use certified Ultra High Speed HDMI cables to guarantee compatibility with all features.

Installation Tips and Common Pitfalls

Once you've chosen the right cable, proper installation is key to avoiding frustration. Follow these steps for a smooth setup.

Proper Connections

Before connecting, turn off both the TV and soundbar. For HDMI ARC/eARC, plug the cable into the port labeled ARC or eARC on both devices. Regular HDMI ports won't carry audio back. For optical, remove the protective caps from both ends, align the connector shape (it only fits one way), and push gently until you feel a click. Avoid forcing it, as the plastic connectors can snap. For coaxial, push the RCA plug in firmly and twist slightly to seat it. Then turn on both devices.

After connecting, set the TV's audio output to the correct source. On the TV menu, look for Settings > Sound > Audio Output and choose the connected type (HDMI ARC, Optical, or External Speaker). The soundbar should automatically detect the input. If not, use the soundbar's remote to select the corresponding input.

Troubleshooting Common Issues

If you get no sound: First, confirm the TV's audio output is set correctly. Next, try a different input on the soundbar. For HDMI ARC, check that both devices support ARC and that the correct HDMI port is used. Sometimes a simple power cycle (unplug both devices for 30 seconds) resolves handshake issues.

If audio cuts out briefly: This often happens with optical cables if the connection is loose or the cable is bent too sharply. Re-seat the cable on both ends and ensure it's not pinched behind furniture. For HDMI, a poor connection or sub-standard cable can cause intermittent dropouts—try a different high-quality cable.

If you get no sound from certain apps: Some streaming apps output audio at different formats. For example, Netflix may send Dolby Digital Plus while a local media player sends PCM. Ensure your TV's audio settings include "Bitstream" or "Auto" format instead of "PCM" to pass through encoded audio to the soundbar. If using optical, note that some TVs only output stereo PCM via optical, even if they can output surround sound via HDMI ARC. Check your TV's manual for format limitations.

If there's lip sync delay: This is common with soundbars. Use the TV's audio delay (lip sync) adjustment to match the audio with the picture. If using HDMI eARC, the TV should automatically adjust, but manual correction may still be needed. Optical cables sometimes introduce a small delay, so setting a delay of 50–100ms often helps.

Future-Proofing Your Audio Setup

Technology evolves quickly. To avoid needing to replace cables when you upgrade your TV or soundbar, consider future-proofing now. The most important factor is support for high-bandwidth audio. If you invest in a good soundbar today, but later buy an HDMI 2.1 TV and a 4K Blu-ray player with Dolby Atmos, you'll want cables that can carry those formats.

For that reason, an Ultra High Speed HDMI cable certified by the HDMI Forum is the safest choice. It supports 48Gbps bandwidth, enough for 8K video and eARC's full suite of audio formats. Even if your current TV only has HDMI 2.0, the cable will work backward and be ready for future upgrades. Optical and coaxial cables are limited by their connector standards—they cannot be upgraded to carry Dolby Atmos or high-resolution audio beyond 24-bit/192kHz. If you ever plan to move to a system with object-based surround sound, HDMI eARC is the only path.

Additionally, consider investing in a well-built cable with braided shielding and robust connectors. A quality cable can last through several devices. For longer runs, pre-terminated optical or active HDMI cables offer reliability, but modular options like HDMI extenders over Ethernet give you flexibility to route through walls.

Conclusion

Choosing the best digital audio cable for your soundbar starts with knowing your devices and your audio needs. HDMI ARC/eARC delivers the highest quality and most future-proof solution, while optical and coaxial remain excellent choices for older hardware or simpler setups. Each cable type has its own strengths, and reliable options from brands like Monoprice, KabelDirekt, and AudioQuest ensure you get clean, consistent sound.

By checking your TV and soundbar ports, understanding the audio formats you use, and selecting a cable with proper build quality and length, you can enjoy rich, immersive sound without signal issues. A smart cable choice today will keep your home theater experience enjoyable for years to come.

For further reading, see Crutchfield's guide to connecting a soundbar, CNET's explanation of HDMI ARC and eARC, and Wirecutter's recommended optical cables.