If you have had a TV, sound system, DAC or amp you’ve probably noticed a lot of ports that are normally placed in the back of the device. If you are not fully accustomed to audio equipment, their functionalities and purpose might escape you. Understanding their function will help in landing you the right equipment to build your own audio sanctuary. This guide aims to lay out the common types of audio output as well as their pros and cons.
Understanding Audio Output
Audio output or audio out simply refers to an audio signal, digital or analog, driven out from one device to another device’s audio input. One such example is a DVD player – some DVD players do not have internal or pre-installed speakers and you are only able to extract sound via the DVD Player’s audio output to an external speaker’s audio input. This can either be done via a cable or wireless connection. This enables you to use an audio equipment as a source and a speaker as the transducer.
Types of Audio Output
Audio signals can be driven out of a device to another device’s audio input via two ways; analog or digital.
Digital Audio Output transmits digital audio signals while analog audio output transmits analog audio signals. They both have their own merits and it is up to you to choose what works best for you.
Analog Audio Output
Depending on the device you are using, these are the various types of analog audio output you can find in your device:
RCA (Stereo audio output)
These are red and white in color circular jacks mostly found in most TVs but can also be found in DACs/amps and speakers. It is usually labelled as an input and output. They are the most common type of analog audio output. The stereo audio output splits audio in two separate channels allowing the audience to experience more dimension of sound.
1. Very popular amongst household audio devices
2. Very easy to set up
3. They are relatively cheap and readily available
1. The colour code system makes it hard to keep in mind their functionality especially in complex systems
2. The many cables in an RCA makes it hard to handle. Although companies are coming up with ways in which they can make all the cables into one; It may take years to face out the cables
XLR output (cannon plug)
It is easily identifiable by its 3-pin connector (XLR3) and even though others exist with various pin patterns, this is the most known. Other patterns are four-pin, five-pin, six-pin, seven-pin XLR connectors and PDN. Mostly found in microphones and other professional audio devices. Used widely as a balanced audio connector for high quality. They are also used for lightning control and low voltage power supply. As the XLR output allows for a well-balanced audio connection, it minimizes the electromagnetic interferences.
1. Increases the sound quality as it minimizes the noise and interferences
2. Can be used even when the source and the receiver are a long distance apart, making it suitable for live performances
1. They have a high purchase price
2. Not readily available
Mini-stereo (TRS connectors)
TRS are initials for Tip, Ring and Sleeve which include the parts of a jack plug which different conductors are connected to. ¼ inch TRS cables are used to carry balanced signals. They consist of two signal wires and a shield. They are used to carry stereo signals meaning that they have both a left and right signal. The mini stereo or 3.5mm audio jack have chords on two channels that means the sound is stereo. They are usually found on personal computers, phones, DAPS but also in consumer microphones or infrared control systems.
1. Easy and convenient to use
2. Used to transmit stereo signals
1. Does not have an extra audio channel for the microphone input
2. Indirectly affects the overall quality of sound
3. Does not cancel noise interference
Multi-channel output or Surround sound
These systems are mostly used in the upgraded tech and modern sound systems. A multi-channel output has the ability to handle a number of audio channels to rebuild the sound on a multi-speaker. It is the main element in a surround sound set-up as the audio output tends to surround the listener in all the corners of their surroundings. These are commonly used in home theatre set-ups. Depending on the number of audio track used, speaker set-up can be grouped using two digits separated by a decimal. For example, a 5.1 surround sound system means it has 5 channels and one low frequency effects channel.
1. The sound quality can be easily manipulated to fit the specific taste of an individual.
2. Offers a luxurious experience
3. Aesthetically pleasing as it gives a statement in a room or a place where it has been placed.
4. Easily accessible to an average person
1. Some Multi-channel output system are aesthetically pleasing but are not fully equipped on the technical side of things
2. Poorly set up surround systems can be so loud to a point where they cause harm on an individual’s hearing ability
3. Some sound adjustments available in sound systems cause unpleasing sounds which are shrill or scratchy
An RF coaxial has two conductors and an insulating spacer. Usually used in the transmission of electrical signals and transmission of Radio Frequency energy where tight impedance and RFI/EMI control is put in use. The insulating spacer is in between the two conductors which is the centre conductor and an outer conductor. Performances of an RF coaxial is measured in aspects of insertion loss, Voltage Standing Wave Ratio (VSWR), frequency, Impedance and shielding.
An RF coaxial has very poor quality and it does not block noise from the surrounding.
1. It is relatively affordable
1. Poor audio quality
2. Does not block noise from the surrounding
3. It is mono signal
The speaker wire ports have inlets that accept bare wires. This audio output connects directly to a device without any kind of plug. They are mostly used to make a connection between speakers and amplifiers. The speaker wire cables have low resistance to allow more power and sound to the speakers from the audio source.
1. Aesthetically pleasing
2. Improves audio quality
1. Some speaker cord type can lead to signal loss which ends up affecting the audio quality
2. It can be dangerous in such a way that stray wire may touch other part of your receiver
Digital Audio Output
Depending on the device you are using, these are the various types of digital audio output you can find in your device
Toslink audio output uses a standardized optical fiber connector system. It is used mainly in consumer audio equipment whereby it carries a digital audio stream. Signals are transmitted from the source to the receiver. They support a number of different media format and physical standards. The optical signal is a red light with a peak wavelength of 650 nm. This causes it to have a range of 5 to 10 metres in its effectiveness.
1. They are not prone to electrical problems like ground loops
2. Have lower losses and can extend a range of toslink system
1. There short range makes them to be temporarily or permanently damaged
2. They are not readily available
3. They are expensive compared to plastic cables
A USB audio simply a digital audio connection used to send music files from a computer to a DAC (Digital to analogue converter). They are mostly found in computers. USB audio output can be used to connect devices like Bluetooth transmitter to allow wireless sound transmissions.
1. Commonly used in laptops and computers for audio transmissions
2. Can handle high music resolution well
3. It is simple to connect an audio interface to a computer
4. Has a high rate of transfer
5. It is inexpensive in their manufacture and production
6. Consumes low power
1. Audio quality is affected by the distance
2. It’s speed is relatively low
3. Does not provide a broadcasting feature
The High Definition Multimedia Interface (HDMI) is the most popular digital audio output found in most devices. It can output both audio and video in high resolutions making it to be one of the most sort out audio output. Used to transmit uncompressed video data and audio data from a device that is compliant with the HDMI.
1. Produces better audio quality
2. It is multipurpose as it can be used to carry both the audio and video signal, therefore, separate cables are not needed in the transmission of audios and videos
3. Supports authentication and encryption
4. Supports a number of audio and video formats for example 720p, 1080i’ 1080p and PAL
5. Does not reduce sound and video quality since it does not compress
1. The distance is limited between 10 to 35 metres
2. Authentication delays leads to switching delays
3. HDMI is expensive compared to analog audio outputs
4. They are difficult to run in multiple locations
Sony/ Philips Digital interface ( SPDIF) is a type of digital audio interconnect used to output audio over reasonably short distances. A coaxial cable is used in the transmission. It is also commonly used to carry two channels of uncompressed digital audio from a CD player to an amplifying receiver.
1. There is no loss in transmission since the digital quality remains the same
2. Can be connected to up to 8 channels of audios
1. Many SPDIF implementations cannot fully decouple the final signal from influence of the source
2. It is prone to noise and interference
3. It has no support for high quality audio as compared to the other digital outputs
A DisplayPort can be easily described as a device whose primary use is to connect a video source to a display device like a computer monitor. It can be used to carry data including video, audio, etc. Has a high video output capability and come in standard and mini-sizes. They can be used in the transmission of audio and video simultaneously.
1. Allows for easy expansion due to the micro-pocket protocol
2. Designed to work for internal chip-to-chip communication
3. Has a high quality output on both audios and videos
4. Has a high band-width and lower cost
1. It is not widely used and many systems do not support it
What are audio input and output?
Audio input and output are channels through which components in a sound system communicate to each other and the real world. For instance, let’s take the example of a simple public address system that comprises a microphone, an amplifier, and a speaker. The microphone takes a sound wave and converts it to an electric signal, which it then sends to the amplifier. The amplifier then amplifies the electrical signal and sends it to the speaker, converting the electric signal to a sound wave.
The success of the whole process pegs on the ability of the components to receive and send signals, whether electric or audio. The audio signal sent out by a device towards another device is called an audio output or an audio out, which is accepted by the target device’s audio input. Simply put, audio outputs produce signals that drive audio inputs.
The output-input process goes through plugs, jacks, screw terminals, or wirelessly through Bluetooth connectivity between audio components. In our example above, the microphone outputs a signal to the amplifier’s input, which the amplifier then outputs to the speakers. Audio gears can either have audio outs or in only, or both. And these ports come in different types and designs to cater to different signal strengths and qualities. Technically, unconnected audio out port will have a signal detectable by an oscilloscope while audio in port doesn’t.
How do I connect audio output?
Audio output in audio sources such as TVs and FM tuners allows you to use alternative speakers other than the inbuilt speakers. Generally, if an audio source has an audio out, there will be marked “output” ports to avoid confusion with audio in ports. Apart from the clear labelling helping ease the connection process, it also prevents the damage that would occur if there is a connection mismatch.
Connecting audio output is relatively easy, but how easy depends on the connection port type and the accompanying settings on respective systems. For instance, let’s say you want to connect a TV to a home theatre system. The first step is to check if the TV audio output ports match with the home theatre receiver’s audio input ports. For example, if you want to connect the two using an HDMI cable, each must have an ARC port.
Once you verify that the audio output/input ports match, you need the respective cable for the connection-in, such as an HDMI cable. Run the line from the TV to the home theatre system, and then activate the individual settings in the two systems by enabling “audio out through HDMI” on the TV settings and changing the audio source to HDMI on the home theatre system. Generally, audio output is of three types: analog, digital, and wireless. You can use any of the three types available on your systems, provided the ports match the audio signal source and the receiver.
How do I choose audio output?
The exact way of choosing audio output on any audio source depends on the audio receivers connected to it and the respective audio out settings. For instance, many modern TVs have numerous wired and wireless audio output options, and you can combine several audio receivers on different ports simultaneously. You can connect your TV to a soundbar through RCA ports or HDMI ARC cable and connect it to Bluetooth speakers wirelessly. But it’s unlikely that your TV can send an audio signal to the two connections simultaneously.
So, you need to know how to switch onto either as need be for a smooth audio experience. Every audio source with several audio output options must either have a dedicated audio source switch or button or, in the case of TVs, navigable settings to select audio output options. And you don’t have to guess your way into these settings, as many user guides have well-elaborated steps to do so.
What is used to output sound?
Audio sources can’t produce sounds on their own as they only have digital audio data. They need hardware and sophisticated processing to turn the digital data into electric signals that speakers can then change to sound waves. Simply put, there must be an “audio processing” device between your audio source electric circuit and the speakers. These audio processors take many forms, from sound cards, onboard audio converters to external adapters. And these devices are what your system uses to output sound.
The working principles of either of these audio processors are pretty similar. They all contain a digital-to-analog converter (DAC) circuit and an input and output port. The input is connected to the motherboard of the sound source while the output connects to speakers. So, the device receives binary data in its input ports and converts it into an audio signal, which it outputs through jacks or other audio out ports.
Understanding audio output will undoubtedly help you to choose the right kind of system for you. It is often easy to get confused with so many different ports, all with different functions and different purposes. Hopefully this guide will help to demystify each of the different outputs out there whether it be digital or analog. Let us any thoughts you have in the comment section below.
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