What is an HDMI audio extractor? My in-depth guide will help you choose the best HDMI audio converter for your setup. Learn how it works and what to look for.
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What Is an HDMI Audio Extractor?
An HDMI audio extractor splits an HDMI source signal into a separate HDMI output and audio output.
In most setups, you won’t need to do this. You simply connect the HDMI output from your source device to the HDMI input in your display device.
But, what if you want to send the picture via HDMI to your TV or projector – and send the audio somewhere else – like a surround sound speaker system?
Well, there are a few ways you might do this, but one easy solution is to buy an audio extractor box.
This will allow you to split the HDMI picture and audio data.
You may also see these devices called HDMI audio converters or splitters.
It is a fairly straightforward concept, and in most cases, installing one is easy enough.
However, once you decide you need one, you can expect to spend anywhere between $20 and $150 for the device.
When Would You Use an HDMI Audio Extractor?
Many devices, such as flat-screen TVs, have a physical or software-based HDMI audio converter built into them.
You need one any time you want to convert an HDMI into an audio-only source.
For example, your TV may receive the sound and picture from your Blu-ray player via HDMI. But, you might want to use the built-in optical audio output to send the TV audio to your speaker system.
In this case, the TV has extracted the audio from the picture and allowed you to send it somewhere else.
But, there are times when a dedicated device is the only way to do this, such as when you are using an analog system.
So with specific equipment, chances are an HDMI to audio extractor is the best way to re-route the audio signal.
In the above example, you could also use an extractor to easily change the audio output type.
If your TV only has an optical output – and your amplifier has digital audio coaxial only – then an audio extractor with a coaxial output can quickly solve this problem.
Just install it before the HDMI goes into the TV – and re-route the audio directly into the amp.
Another practical application for an extractor is HDMI streaming devices like the Amazon Fire Stick or Roku HDMI devices.
You can plug the stick into the HDMI input and then split the video and audio between a TV/projector and an amplifier.
The example above converts the HDMI audio to optical. However, depending on your equipment, this could be coaxial or analog stereo audio.
You could also use an extractor to send the audio to a headphone amplifier.
How to Choose an HDMI Audio Converter
As stated, most smart TVs and other entertainment systems these days come with a built-in audio extractor.
You should only need one if you are working with a collection of equipment that you are trying to get to function together.
Often, people discover that they need an audio extractor after much frustration trying to get an incomplete system working.
So, if you discover you need an HDMI audio extractor, there are some things to consider.
Keep in mind that each of the factors explored below represents a range of connectivities and source-support types.
The way to save money on your HDMI audio converter is to find one that does exactly what you need it to do and no more.
If you’re willing to spend more, a more expensive audio extractor is likely to do more and therefore be more likely to fulfill the needs of your specific use case.
In short, the more you research the device you’re considering for purchase, the more able you will be to make a cost-effective purchase.
Different Audio Output Types
Different types of HDMI audio extractors will work best with different systems.
So before you buy, know which kind of audio you need to send so that you can match an extractor to it.
For example, if your speaker system has an optical input, it would be best to buy an extractor that outputs optical audio.
If not, then you might need yet another converter before you can connect everything together.
This then starts to get over-complicated.
The most common audio output types are:
Some HDMI audio extractors will work with all of the above and more, others only one.
Multiple Inputs and Outputs
You could buy a simple extractor with a single HDMI input/output and the correct audio output for your needs to save money.
These models will cost more money but could provide you with precisely the right connections for your setup.
You will find some models that have a built-in headphone output. Others come with a volume control on the unit.
These aren’t going to be required for most people – but they can be a useful extra depending on your circumstances.
Stereo and Multichannel Audio Support
Which audio formats does the unit support, and do you need more than one kind? Check for the following:
- Stereo analog audio
- Dolby/DTS 5.1 surround sound
- Dolby Digital Plus
- Dolby TrueHD/DTS-HD Master Audio
- Dolby Atmos
Most systems will cover Dolby/DTS 5.1, Dolby Digital Plus, or both.
However, fewer will handle Atmos and the high-resolution audio formats. Fewer still will support all three.
The critical question is, which audio formats do you need to send?
A simple device with analog stereo audio outputs might be all you need if you just have an old stereo speaker system with no digital inputs.
Simultaneous Audio Output
If you have an extractor with more than one audio output type – you may find some models will output audio from all the outputs simultaneously.
This might be helpful as you could, for example, send digital audio and stereo analog audio to different sound sources. For example, you could have the same audio going to your TV and soundbar – and then use them at different times.
Check the model that you buy if you think this might be useful.
Video Resolution Support
Check for video resolution support. It should meet or exceed 1080p/4K to meet common current performance standards.
If you want to pass a 4K video signal to your display device, your audio extractor will need to support 4K signals.
But, if you only need 1080p video, you can often save money and buy a cheaper model.
Other Supported Technologies
There are numerous video and audio technologies in modern AV equipment that you may wish to use in your system.
The crucial point is to ensure that any HDMI extractor device will allow these to pass through. If not, then you may be disappointed with the results.
Look out for:
- HDMI-CEC: HDMI control
- HDCP: copy-protection
- EDID – sometimes required to make sure the receiving device knows which type of audio it is getting
- HDR: high-dynamic range video
- Dolby Vision: a type of high-dynamic range video
- HDMI-ARC: passes audio to and from the destination device
Dolby Vision is quite common these days. Make sure the device you choose offers the support you need.
Support for Apple TV and HDMI Streaming Sticks Like Roku, Fire TV and Chromecast?
Streaming devices come and go quickly, and the standards are rapidly changing. Ensure the HDMI device you purchase is compatible with the streaming device you intend to use it with.
How to Connect HDMI Audio Extractors?
The process of connecting one of these units is a simple one.
The best advice I can give is to have a clear picture in your head of where the video and audio signals are coming from – and where you want them to go.
- Keep the power off. As long as the power is off, you are unlikely to cause any damage from improper connections.
- Be sure you have the right HDMI cable. Use the cables that came with your device. Older cords are unlikely to have the suitable bandwidth or support for newer formats. Remember, support for the video and audio formats mentioned above also applies to your HDMI cables.
- Check that you have the correct audio cables. You may output SPDIF using Toslink fiber optic audio cables or digital audio coaxial RCA cables, or output analog using 3.5 mm stereo cables.
- Connect all the cables. What cables go where depends on the device you have. Ensure to follow the manufacturer’s instructions, match labels, and do not force plugs that don’t fit easily.
- Connect the power cable. Once you’ve done all that, it’s time to connect the power. If you have made a mistake, disconnect the power again before correcting it.
- Find the proper input channels. Now, find the correct inputs on the devices you’ve connected. To see the picture, select the correct HDMI input on your TV. And, on your amplifier or audio playback device, select the right input so you can hear the sound.
Unfortunately, all of this is device-specific, so you’ll have to take your time and be sure your connections are right before switching it on again.
Here is a simple connection diagram explaining how to connect a Blu-ray player to a TV and amplifier using coaxial digital audio:
This is another scenario where audio extractors can be helpful.
In this case, for people with an older AV receiver that doesn’t have HDMI inputs. Or, it may be a stereo amplifier – which often doesn’t have HDMI connections.
Simply pass the HDMI connection through to your TV – and connect the alternative audio output into your AV receiver or amplifier.
What Is the Best HDMI Audio Splitter/Extractor?
With several different extractors to choose from, it can be tough to pick the one you want.
Remember, the essential thing is ensuring that the unit supports all the video and audio formats you want to use.
A good all-rounder is the J-Tech 3×1 HDMI audio extractor:
With a total of 3 inputs, the J-Tech extractor can also serve as a switcher.
It can reproduce the audio from a game console or a streaming device on anything from a simple 2-speaker setup or soundbar to a highly polished surround-sound system.
This unit is great value on Amazon and is a very versatile HDMI audio extractor for the price.
If this is more than you need, you can also buy cheaper models with fewer inputs.
Frequently Asked Questions
Can I Get the Audio Out From HDMI?
Yes, one of the best ways is to buy an HDMI audio extractor. This device will receive an HDMI source and split the output into HDMI for video and a separate audio output.
How Do I Convert HDMI Audio to RCA?
If you want stereo RCA audio, then buy an HDMI audio converter/extractor with a stereo analog output. If you need digital RCA audio, then your audio extractor will need a coaxial SPDIF output.
Does HDMI Carry Analog Audio?
HDMI cables will carry only digital format audio. Therefore, there is never any need to have an analog signal since these devices are only used with digital equipment. You can use an audio extractor to convert the digital HDMI audio to stereo analog.
Do HDMI Audio Extractors Cause Lag?
Generally, no. A well-made model should pass through the signals with little effect on the video and audio timing. However, some playback devices allow you to compensate for minor timing issues between sound and picture if you do see lag.
Can I Use HDMI for Video and RCA for Audio?
Yes, you need to buy an HDMI audio converter that will split the picture and sound between HDMI and RCA audio.
Does an HDMI Audio Extractor Degrade Sound Quality?
Not usually. Because it usually delivers a digital signal, the output should remain unchanged. Any sample rate changes may affect the audio quality, for example, but not by a direct HDMI connection.
About Home Cinema Guide
Paul started the Home Cinema Guide to help less-experienced users get the most out of today's audio-visual technology. He has worked as 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.