What Is an HDMI Audio Extractor and How Does It Work?
An HDMI audio extractor is what I use to set up my Xbox, Chromecast, and Blu Ray player into my TV and soundbar. Here is a detailed article describing what it is and how it works.
An HDMI audio extractor is a device that splits the audio and video signal from an HDMI source. It allows the audio signal to be sent to a 2-channel stereo analog source or a digital audio source using an optical S/PDIF jack that supports up to 7.1 Dolby digital surround sound and sending out an HDMI video signal.
This article will cover what HDMI is so we can then get a clear understanding of precisely what an HDMI audio extractor is and how it works.
We will dive deep into how it works and look at what external and internal factors could affect its quality of video and audio signals. We will look at its specifications and features, allowing us to understand what options we have in terms of routing audio signals to different audio systems (analog and digital) and what audio quality we can expect.
We will then look at what makes a good HDMI audio extractor, and finally, we will go over the top audio extractors currently available.
Also read: How Do HDMI Surge Protectors Work?
What is HDMI
HDMI stands for High-Definition Multimedia Interface. This is probably the most frequently used HD signal interface for transmitting both high-definition video and audio over a single cable.
It transfers as uncompressed video data and compressed or uncompressed digital audio data. It has replaced analog cables, which used to require separate audio and video cables such as VGA and audio jack cables.
HDMI uses the Consumer Electronics Association/Electronic Industries Alliance 861 standards (EIA/CEA-861). These standards Implement and define video formats, the transport of compressed and uncompressed LPCM audio, and also implements EDID
EDID (Extended Display Identification Data) is the AV industry standard for your output display, your screen, TV, or projector. It automatically communicates with your AV source device (for example, your Amazon Fire TV Stick or DVD player). So as you can see, this is crucial in the implementation of HDMI.
HDMI is used both in the commercial AV sector and is most definitely the cable of choice for the home entertainment market. HDMI is used to connect digital TVs, DVD players, Blu Ray players, Xbox, Play Station, Apple TV, and more to other AV sources.
We are now seeing more and more AV devices use HDMI as the standard source of throughput. HDMI is even featured on PCs, MACs, Laptops, car infotainments systems, and many more.
What is an HDMI extractor?
Now that we know what HDMI is and that we use it for AV components to send audio and video signals across one cable, let’s look at what an HDMI extractor is.
An HDMI audio extractor is a device that is used in your AV setup that splits your HDMI signal, which contains both video and audio signals.
It allows you through analog audio jacks or a digital S/PDIF jack to separate and direct the audio signal into a new analog or digital source, enabling you to play that audio signal on a separate device.
In simple terms, you can split the HDMI audio and send it to another device, and that device plays the audio. This is great and Is used to integrate your digital home theatre system with your analog home audio system.
It can also send digital audio through an optical S/PDIF port to your digital home audio system if the HDMI extractor allows it.
How does an HDMI extractor work?
An HDMI audio extractor works by converting the incoming HDMI signal into separate video and audio signals. The output video signal will still be a digital HDMI signal, while the audio will be turned into a 2-channel stereo audio signal and a digital audio signal depending on whether the audio extractor has this capability.
HDMI audio extractors also have the ability to extract 5.1/7.1 Dolby digital surround sound, which is sent through the optical jack. You can usually select which audio signal you would like to use via a mode switch.
2-channel stereo signal
A 2-channel stereo audio signal is extracted from your incoming HDMI cable and is put through both the analog audio output jack and the optical S/PDIF jack.
This means you are able to send either an analog stereo audio signal or a digital stereo audio signal to either an analog audio system or a digital audio system maximizing the capability.
Surround sound
Depending on your audio extractor, 5.1 or 7.1 channel surround sound signal is extracted from your HDMI cable and put through the optical S/PDIF jack. This signal is best when used in conjunction with modern audio systems that allow for Dolby digital surround sound.
One thing to note is that an audio signal that matches the audio mode is also sent through the HDMI output port. This means that advanced surround sound and uncompressed audio cannot be sent through the HDMI output port.
Hence, it would be best if you did not use the audio extractor to send HDMI audio to a surround sound system for the best sound quality.
How would you use an HDMI audio extractor?
We will go through a real-world example explaining the application of an HDMI audio extractor.
Let’s say you have these AV systems on hand
- HDMI audio extractor with the capability of 5.1 or 7.1 Dolby surround sound
- Amazon Fire TV Stick
- A TV that is not a smart TV that has an HDMI input
- A 5.1 or 7.1 Dolby digital surround sound system that has an optical input
- A vintage Hi-Fi that has a stereo analog input
Theoretically, what we would like to happen is that we would be able to stream content via the Amazon Fire TV stick and have the audio play through our 5.1 or 7.1 surround sound system when we are streaming movies. Then have the audio play through our vintage sound system when we stream Spotify. This is how we would do it.
You would connect your Amazon Fire TV Stick into the input of the HDMI audio extractor. What would happen here is the audio extractor would take the signal from the Fire TV Stick and split it into a digital video signal and then a stereo analog signal, and a digital optical signal.
Suppose your audio extractor had a mode switch for additional 5.1 or 7.1 Dolby surround sound (which in this example it does). In that case, we could switch modes playing the digital surround sound signal through the optical jack or the analog stereo signal through the RCA jacks.
You would then run the HDMI output to your TV, the stereo jack signal to your vintage Hi-Fi system, and then the optical jack signal to your 5.1 or 7.1 surround sound system.
All you would need to do then is switch between your stereo signal when listening to music and then to your digital surround sound signal for movies via the mode switch. That’s it.
Do HDMI cables affect the quality of an HDMI audio extractor signal?
If an HDMI capable is built to spec and functions properly, there is no need to spend extra money on something fancy. This is because a digital transmission isn’t nearly as susceptible to interference as an analog connection. Hence it either works, or it doesn’t.
This doesn’t mean it’s a great idea to purchase the cheapest HDMI cable either. HDMI cables that utilize the correct construction materials can make a big difference with regard to high performance.
Copper wiring
This doesn’t mean that you need to find HDMI cables that are made from costly materials. HDMI cables that use steel are not very good conductors, which means you should avoid these if at all possible. Cables made of copper-coated steel are not that good either. What you need to do is get a cable that has pure copper wiring inside.
The good news is that copper cables are relatively cheap and you don’t need to get any fancier material than this, for example, silver-plated copper.
Wire gauge
We now know to get pure copper wiring for an HDMI cable. The next most important thing is the thickness of the wire inside. The thickness of the wire is measure in gauges, and a low gauge will mean a thicker wire while a higher gauge will mean a thinner wire.
If you want your audio and video quality to be pristine, then a general rule of thumb is that your HDMI cable length should not exceed 1.5 meters with a thin 32-gauge wire.
However, if you increase the thickness of the wire, you can safely increase the distance accordingly. This can take you up to an 8m cable, which must have a 24-gauge wire.
Connectors
The connectors on the end of the cable, if possible, should be gold plated if you can find it. This is not the external connector but the pins located inside the connector. Gold plated pins will give longevity to your cables and not necessarily increase their performance, however.
Does an HDMI audio extractor affect the quality of the audio and video signal?
The factors that would affect the audio and video quality would be the actual HDMI cables that are used (as we discussed). However, if they are made of copper wire and are the correct length, that will not pose a problem.
Sample rates
The next factor to consider is the sample rate. The sample rate is measured in kilohertz (kHz) and is how often an AV signal is received. A higher sample rate means better emulation of an analog signal.
HDMI allows up to 8 channels of uncompressed audio at 16-bit, 20-bit, and 24-bit, with sample rates of 32 kHz, 44.1 kHz, 48 kHz, 88.2 kHz, 96 kHz, 176.4 kHz, and 192 kHz.
Hence the only thing to consider is the sample rate of your HDMI audio extractor. If your audio extractor has a low sample rate, then the audio will not be of the highest quality; however, the notice in sound quality is negligible to human ears. Another thing to note is that your entire AV system setup will only work as well as the device with the lowest specifications.
This means if you have a device in your AV system that is sending a 48KHz signal and all your other devices are running at 192KHz, the entire system will only run at 48KHz.
HDMI versions
The current HDMI version is 2.1, and since the inception of HDMI, we have had sample rates of up to 192KHz. The HDMI versions that come with an audio extractor should be equipped with HDMI 2.0, which means handling sample rates for 7.1 Dolby digital surround sound should not be a problem.
However, remember that an audio extractor also sends an HDMI video signal. Depending on the HDMI version your audio extractor has, this could impact the video quality to a degree. Here is a chart of the HDMI versions and how they have changed regarding video quality per version.
| HDMI Version | 1.0 1.1 1.2 | 1.3 | 1.4 | 2.0 2.0b | 2.1 |
|---|---|---|---|---|---|
| Bandwidth (Gbps) | 4.95 | 10.2 | 10.2 | 18 | 48 |
| Color Depth | 24 | 48 | 48 | 48 | 48 |
| Mx resolution | 1920x1200 60p | 2560x1440 60p | 3840x2160 30p | 3840x2160 60p | 7680x4320 60p, 3840x2160 120p |
What makes a good HDMI extractor?
We now know what an HDMI audio extractor is, how it works, and what functions and characteristics it has. With this information, we can say that a good HDMI audio extractor features HDMI versions 2.0 or 2.1, and an audio extractor has both a stereo analog jack and an optical S/PDIF jack.
Then it should be able to support either 5.1 Dolby digital surround sound or 7.1 Dolby digital surround sound. Another facet that could make an excellent audio extractor is if it had many HDMI input jacks. This means you could connect and manage multiple devices simultaneously.
These are the main factors that would make up a high-end HDMI audio extractor; however, you do get audio extractors with fewer features and are still top quality. Lucky enough, I have a list of the top 5 HDMI audio extractors here.
Top 5 HDMI audio extractors
iArk Power Switch
The IArk power switch allows up to 3 HDMI source devices (like PC, PS4, Xbox, Blu-ray player, cable box, DVR, Chromecast, Fire TV, Apple TV) to be connected to one HDMI port on your HDTV, monitor, or a projector. This audio extractor has an optical S/PDIF output that supports up to 5.1 Dolby Digital and DTS and has an analog RCA output.
This device supports an auto-switching function which can also be turned off, and it includes an IR remote for manual switching
The HDMI in port supports up to 33 feet AWG26 standard HDMI cables, and the HDMI output supports up to 50 feet.
J-Tech Digital 4K 60HZ HDMI Audio Extractor
The J-Tech Digital has a 2-channel analog stereo output or multi-channel Audio (S/PDIF) output. One thing to note is the unit will only pass Dolby Digital audio formats and will not decode these formats for the analog output.
If you do happen to use the analog output, make sure your source is set to PCM audio. It supports 4K Ultra HD with HDMI 2.0 as well as HDMI 2.0b (18Gbps) HDCP 2.2 and DVI. It supports 5.1 Dolby digital surround sound and has a sample rate of up to 192KHz.
View HD Uhd 3×1 A
The View HD S/PDIF Toslink optical audio output Supports ARC and incoming HDMI Audio formats up to Dolby Digital 5. 1 and Dolby Digital Plus, and the analog RCA Audio output supports incoming 2-channel stereo PCM / LPCM Audio format.
It has a built-in input auto switch function that can be enabled or disabled as well as a built-in compatibility mode to support older versions of 4K displays.
It has three audio EDID settings and uses 2-channel settings for the stereo 3.5mm headphone output. Then it has a 5.1 Dolby digital setting for the optical audio output.
Prozor 3×1 Switch
The Prozor is not only an HDMI 3×1 Switch with PIP function but also an HDMI audio extractor. It sports a 3.5mm to RCA cable and has three modes of audio output.
The switch is a 3 HDMI input converter to 1 HDMI display optical Toslink Output, which supports 5.1 Dolby digital surround sound or stereo audio output. It also supports the function of automatic, manual, or remote switching.
It supports HDMI version 1.4, which is a resolution of up to 4K 30hz. It is made from high-quality ABS plastic and features 24K gold-plated connectors to reduce signal loss.
It has a wide compatibility range and is suitable for various HDMI sources like Roku or Chromecast, Amazon Fire TV, PS3/4, Apple TV, Xbox, PCs, and more.
Conclusion
We conclude that an HDMI audio extractor is a must-have device if you need a way to separate your audio and video signals in your home entertainment system so as to route them to separate AV devices.
It can help bridge the gap between your home video system and your home audio system, by extracting the audio signal from an HDMI cable and sending it through a 2-channel stereo analog jack or an optical jack that can support up to 7.1 Dolby digital surround sound.
Depending on your needs, you can set up any AV system and route the video and audio signals to any device you like creating a home entertainment system that you will be emersed in.
There are many ways in which you could use an audio extractor. You can setup up, connect and link all your home entertainment devices (like your Xbox, PS4, Blu Ray player, DVD player, Chromecast, Amazon Fire Tv Stick, Apple TV) and everything in between.
We discussed and learned every function, detail, and feature there is to know about an HDMI audio extractor leaving no stone unturned, hopefully helping you understand it better and helping you decide if you require one for your home entertainment system or not.
Jason is a home theater expert with over 10 years of experience in setting up home cinema rooms and systems. What started out as a hobby soon transformed him into an authority in the audio-visual field. He is passionate about providing readers with accurate and up-to-date information on the latest audiovisual technologies and their applications for home theaters. Read more about Jason.
