You will find stereo analog RCA audio inputs and outputs on most audio-visual devices. They can be a great way of connecting the sound in your audio system.
These connections use what is known as an RCA plug – but may also be called a phono connection.
However, just because they are a common connection type, it doesn’t necessarily mean you should use them to connect your audio.
This article looks at the standard RCA cable and plug, suggests when to use it, and highlights ways of converting it to other AV connection types.
Main Topics
What Does a Stereo Analog Audio Connection Do?
A stereo analog audio connection transmits two channels of analog audio between devices. It only supports stereo analog audio, not digital. But you can also use it for single-channel mono audio that requires just one wire.
Analog is more prone to interference than digital audio. However, the sound quality depends on factors like wire gauge, shielding, and good-quality connectors.
This type of connection is a simple and cost-effective method of sending audio between devices and is still useful in the digital age. It is commonly found on older televisions, turntables, cassette decks, and audio-visual devices like video cameras.
While basic, it remains a practical way to transmit stereo or mono analog audio between devices.
What Does the Connection Look Like?
An analog audio connection for a stereo RCA plug looks like this:
It is either an input or an output, which will be labeled next to the port on your device.
Outputs send the audio from one device to another, while inputs receive audio from somewhere else. The connection on your device depends on what the device is for.
For example, a DVD player or cable TV box often has a stereo RCA output for sending the content audio to a separate sound system.
But an amplifier usually has a stereo RCA input for receiving stereo audio from the DVD player or cable TV box.
The RCA connectors are usually colored white for the left channel and red for the right channel.
What Does the Cable Look Like?
Stereo RCA audio cables look like this:
They have two RCA connectors at each end – one for the left and one for the right channels. The convention is to color the right channel red and the left channel white. However, this is to help you wire your equipment together.
You can switch this around, but you must ensure the cable connects to the same color port at each end.
You may also come across a cable that isn’t colored red and white. That’s OK; you can still use them for this connection type. Simply connect the same color to your devices’ left and right jacks.
An RCA plug is also commonly known as a phono plug or connector. So if you hear that term, it means the same thing. You can also use these cables for analog multichannel audio.
What is an RCA Cable? Don’t Confuse the Different Types
It’s easy to confuse some terms in home theater because they are similar. A good example is an RCA cable.
You might need an RCA cable, and it will be the cable I am discussing here. However, an RCA cable may also refer to the cable used for sending coaxial digital audio (and wiring subwoofers).
Coaxial digital audio connections are single RCA female connectors – often color-coded black or orange.
While you could use one of the wires from a stereo analog RCA cable to connect coaxial audio, I don’t recommend it.
Coaxial RCA cables are made to a higher specification to avoid disrupting the digital signal, so you should buy an RCA cable designed for digital analog audio.
When Should You Use 2-Channel Analog Audio?
An analog stereo audio connection still comes with most audio-visual devices. However, in many cases, you will not need to use it.
If your device has an HDMI port, optical or coaxial digital audio connection, use these to send the audio between your devices. These are all digital connections that support stereo and multichannel audio.
However, if these are unavailable, stereo audio RCA cables are reliable for sending sound between devices.
| Audio Connection Type | Pros | Cons |
|---|---|---|
| Stereo Analog Audio | Simple design. Widely compatible with various devices. |
Susceptible to electrical and magnetic interference. Quality may degrade over long distances. |
| Multichannel Analog Audio | Gives individual channels of surround sound audio, providing a fuller audio experience. | Numerous cables can make it bulky and complex to set up. May also suffer from signal degradation over distance like stereo analog audio. |
| HDMI | Supports high-definition audio. Can carry both audio and video signals. |
Not all devices have HDMI ports. Cables can be expensive. |
| Coaxial | Good for long distance transmission. Less susceptible to interference than analog connections. |
Limited to digital audio signals only. Connectors may not be as durable as other types. |
| Optical (TOSLINK) | Similar to coaxial audio, but more common. Good for Dolby Digital and DTS multichannel audio formats. |
Can’t carry high-resolution audio formats like HDMI. Cables are delicate and bend easily. |
You will often find this type of connection paired with a video input or output connection, which you will use to send the audio for the video signal.
For instance, a composite video signal connection can only send video information, so it will usually have stereo analog audio connectors next to it, which will pass the audio for the composite picture.
You must connect the video and audio connectors to hear the picture and sound. An example of this is pictured below:
Can You Convert Stereo RCA to HDMI?
You can convert stereo audio RCA to HDMI with the correct adapter. Converting from RCA to HDMI can be required to play video and audio signals from old AV devices with only RCA outputs.
For example, you might have old family videos on VHS tapes that you want to watch on a modern TV.
Most new TVs don’t have RCA inputs, so you need a way to connect the RCA outputs of your old VHS player to the HDMI input of your television.
To do that, you will need an RCA to HDMI converter like this:
- For compatible game consoles VHS players, DVD players and cable boxes
- Converts to 720p or 1080p digital video
- 1 meter RCA and HDMI cables at either end
- Supports PAL, NTSC & SECAM video
- For RCA to HDMI only - not bi-directional
On this converter, you should connect the male RCA connectors to the three RCA outputs on your player. The yellow cable is for composite video, while the red and white wires are for stereo left and right analog audio.
Then, the HDMI connector at the other end goes into a spare HDMI input on your TV. You must also wire the supplied power cable to a nearby 5V power connection.
If you only want to convert stereo analog audio, you need only connect the white and red cables. Then you can connect them to a suitable amplifier or soundbar.
This device converts analog composite video to 60Hz 720p or 1080p video, and the stereo analog audio will also pass through to the TV via HDMI.
Please note that this converter is for RCA to HDMI transmission only.
You must be clear about which way you wish to convert the signals, or you may buy the wrong device, which won’t work.
Converting HDMI to RCA Stereo Audio
If you need to convert the other way, from HDMI to RCA, then you will need a different converter, like this:
- For Apple TV, Roku, FireStick, Blu-ray and DVD players
- Connect any 4080i to 1080p HDMI output to a PAL or NTSC analog input
- 1 meter cables at both ends
- Power required
- For HDMI to RCA conversion only - not RCA to HDMI
This device will convert the HDMI signal to separate composite video and stereo audio connections.
If you don’t want a converter with cables, you can buy a simple converter box model. In that case, you must provide cables and wire them into the box and your AV devices.
Another solution is to buy an HDMI audio extractor box that will split the video and audio signal, allowing you to connect the stereo RCA output to a separate amplifier or soundbar.
Frequently Asked Questions
What Does RCA Stand For in Cables?
RCA stands for Radio Corporation of America, which developed the audio-visual connector and cable in the 1940s.
Is an RCA Connector Only Used For Audio Signals?
RCA connectors transmit various audio-visual signals, most notably stereo left and right analog audio, but also coaxial digital audio. However, composite and component ports also use RCA connectors for sending video signals.
Are RCA and HDMI the Same?
RCA and HDMI are two different ways of sending audio and video signals. HDMI is a digital connection for transmitting video and audio through a single cable. In contrast, RCA connections primarily send analog audio or analog video signals. However, coaxial digital audio connections also use a single RCA connection.
What Do RCA Cables Connect To?
RCA cables link things like CD players and amplifiers using special ports called RCA connectors. The cables commonly carry sound from one device to another but can also transmit analog video signals.
Are RCA and AV Cables the Same?
RCA cables are AV cables that transmit video and audio signals between RCA input and output connections. While an RCA cable can be called an AV cable, there are several more types of AV cables like HDMI, optical and S-Video.
About The Author
Paul started the Home Cinema Guide to help less-experienced users get the most out of today's audio-visual technology. He has been a sound, lighting and audio-visual engineer for around 20 years. At home, he has spent more time than is probably healthy installing, configuring, testing, de-rigging, fixing, tweaking, re-installing again (and sometimes using) various pieces of hi-fi and home cinema equipment. You can find out more here.
