Optic Cable for TV: Picking the Digital Audio Lead
Quick answer / TL;DR: An optic cable for TV runs from the set's square optical output to a soundbar, an AV receiver or a DAC. Most televisions sold through 2026 still fit the port, usually beside the HDMI inputs. Buy 1 m when the soundbar sits on the same shelf and 1.5 to 2 m when the set is wall-mounted and the lead has to drop behind the panel. Confirm that the plug body clears the bracket, and set the television's digital audio output to PCM or Bitstream to match what the far end can decode.
An optic cable for TV is a short, thin lead that takes the sound out of the television as pulses of light and hands it to a device that plays it better. The socket on the set is the square one with the small shutter, labelled Optical, Digital Audio Out or TOSLINK, and it has outlived almost every other connector on a television back panel.
Buyers arrive at this page with a set already on the wall and a soundbar still in its box, so the useful questions are practical ones: does this television have the port, how long should the lead be, and will the plug clear the bracket.
Why the Socket Is Still There
Television makers have had every reason to drop the optical output and almost none of them have. The port costs a few cents, it carries no handshake, and it is electrically isolated: light crosses the gap, so a ground loop between the set and an amplifier cannot hum through it. That last property is why the socket survives on sets that already have HDMI eARC. A wall-mounted panel with a soundbar on a bracket, a set feeding an older receiver in a cabinet, a hotel room where the audio reaches a distributed system – all are solved by a lead that carries only sound, one way, with no negotiation.
Which sets still carry it
Across the 2026 ranges the optical output is close to universal on sets of 43 inches and up, and it appears on most 32-inch models as well. The exceptions are worth knowing. The cheapest small sets sometimes ship with HDMI and a headphone jack only. Monitor-style televisions, the ones sold without a tuner, often skip it. So do a few ultra-slim designs where the chassis has no room for the shutter assembly. The specification sheet settles it in one line – look for Digital Audio Out (Optical), Optical Out or S/PDIF – and the back panel settles it in five seconds, because the square socket with the amber glow inside is unmistakable.
What the Port Feeds
| Device at the other end | What it wants from the set | Cable note |
|---|---|---|
| Soundbar with an optical in | Stereo PCM or Dolby Digital | The common case, 1 m |
| AV receiver, older model | Dolby Digital 5.1 bitstream | 1.5 m, the rack sits further off |
| Stereo DAC and amplifier | Two-channel PCM only | 1 m, set the set to PCM |
| Optical input on powered speakers | PCM, some take Dolby | Read the speaker's spec first |
| Capture box or small mixer | PCM stereo | 1 m, keep the run short |
The table covers the devices that account for nearly every optical lead sold for a television. What matters is that the port is an output only, fixed by the set's own format menu, and that the device at the far end has to decode whatever the set is told to send. A soundbar with a Dolby Digital badge will take a bitstream. A small desktop DAC will not, and will sit silent until the television is switched to PCM.
The soundbar case, the common one
A soundbar on the same shelf as the set is the purchase that drives this page. The lead is short, 1 m covers it with slack, and the connection is one plug at each end with nothing to configure beyond the format menu. The advantage over HDMI ARC is dull but real: the optical path cannot be confused by CEC, it does not switch the television's input when the bar wakes, and it works with bars that predate ARC by a decade. For a bar with its own remote and its own volume, optical is the calmer of the two connections.
Length and Clearance on a Wall-Mounted Set
- 0.5 to 1 m – soundbar on the same shelf, the set on its stand
- 1.5 m – wall-mounted set with the bar on a bracket below
- 2 m – the drop behind the panel to a low shelf
- 3 m – receiver or amplifier in a cabinet to one side
- Beyond 5 m – only with a powered extender, light fades with distance
Two physical details cause more returns than any electrical one. The first is clearance: a wall-hugging bracket can leave 20 to 30 mm between panel and plaster, and a standard optical plug body is about 12 mm deep before the cable bend begins, so a right-angle plug is often the difference between a lead that seats and one that hangs. The second is the bend radius. Plastic fibre dislikes a tight curve; a lead that leaves the socket and turns 90 degrees through a bracket arm will lose signal, and a slow loop costs nothing.
The Settings Side, in One Line
One line is enough: set the digital audio output to the format the far end decodes, and turn the internal speakers off. In practice that means PCM for a stereo DAC or a pair of powered speakers, and Bitstream, Dolby Digital or Auto for a bar or receiver that carries the badge. If sound is present but thin, or the bar shows a stereo indicator while a film is playing in 5.1, the set is downmixing because it was left on PCM. If there is no sound at all, the far end cannot decode what is arriving.
A Checklist for the Television Side
- The socket is present and labelled Optical or Digital Audio Out
- The far end has a matching optical input, not a coaxial one
- The lead leaves the bracket without tension at either plug
- The plug body clears the wall plate or the bracket arm
- The output format matches the decoder at the far end
- The internal speakers are off, so the two do not overlap
All six are worth doing before the set goes back on the bracket. The format check is the only one that needs the remote, and it is worth doing with a film playing, because a menu that says Dolby Digital does not always mean the set is sending it. Everything else is settled at the point of purchase, which is why the length and the plug body belong beside the connector type.
Optical leads for televisions are stocked from 0.5 to 5 m, in straight and right-angle plug bodies, with the square TOSLINK connector at both ends; the catalog lists the length, the plug shape and the bend relief per part number.
Related reading: The HDMI alternative on the same panel, weighed up: is eARC better than optical — is-earc-better-than-optical
Related reading: The far end of the same lead, the amplifier side: optical cable for a receiver — optical-cable-receiver
Frequently Asked Questions
Does every television still have an optical output?
Nearly all sets of 43 inches and up sold in 2026 have one, and most 32-inch models do too. The exceptions are the cheapest small sets, monitor-style televisions without a tuner, and a few ultra-slim designs. Check the specification sheet for Digital Audio Out (Optical), or look for the square socket on the back panel, before buying a lead.
How long should the lead be for a wall-mounted set?
Measure the drop from the socket to the soundbar or the cabinet, then add 300 mm of slack. A bar on a bracket below the set usually needs 1.5 m, a low shelf needs 2 m, and a receiver in a side cabinet needs 3 m. Add length for every bend around a bracket arm, because the fibre does not like tight curves.
Why is there no sound through the optical lead?
Check the format first. A stereo DAC or a pair of powered speakers stays silent when the set sends Dolby Digital, and a soundbar stays silent when the set sends something it cannot decode. Set the television to PCM for stereo devices and Bitstream for a bar with a Dolby badge, then confirm the plug is fully seated at both ends.
Is optical better than HDMI eARC on a television?
Optical is simpler and more predictable: one direction, no handshake, no CEC, and electrical isolation that removes hum. HDMI eARC carries more – Atmos, Dolby Digital Plus, higher bit rates – and lets the television remote control the bar. For a stereo bar or an older receiver, optical loses nothing. For an Atmos bar, eARC is the only path.
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