Can I use a USB port as an audio output?

What is a USB port?

USB (Universal Serial Bus) ports are common interface ports found on most computers and consumer electronics devices. Their main purpose is to enable connectivity and communication between devices through cables. There are several types of USB ports, with different shapes, sizes, and capabilities:

USB-A – The standard rectangular USB ports found on computers, hubs, and devices. Used for connecting peripherals like mice, keyboards, printers, flash drives, external hard drives, etc.
USB-B – Squared shaped ports found on devices like printers, scanners, cameras. Used for connecting these devices to a computer.

USB-C – Oval shaped reversible connector found on newer laptops, smartphones, and accessories. Supports both power delivery and data transfer.

In terms of power delivery, USB ports supply DC power at either 5V, 9V, 15V or 20V levels, depending on the USB version. For data transfer, USB connections can achieve speeds up to 20 Gbit/s for USB 3.2 Gen 2×2. This allows high bandwidth applications like connecting external displays, high resolution webcams, audio interfaces, and fast data transfers from external drives.

Overall, USB ports provide a standardized way for computers and electronics to share power and communicate data through simple cable connections. Their versatility and ubiquity has made them an essential component of modern computing setups.

(Source: https://techfolder.org/how-can-monitors-be-connected-by-usb-explained/)

USB Ports for Audio Output

USB ports can be used for audio output from computers, phones, and other devices, though there are some limitations. Audio signals over USB can be transmitted either as analog or digital data ¹. Analog audio output over USB requires the device to have an integrated digital-to-analog converter (DAC). Digital USB audio, such as USB Audio Class 1.0 and 2.0, transmits the audio as digital data which then requires an external USB DAC on the receiving end to convert to analog for playback. Some operating systems like Windows 10 have native drivers to support USB Audio Class, while on Android devices it may require manufacturer specific drivers or apps for USB audio out ².

USB audio has some advantages over other connections like being able to transmit multiple audio channels, high bit depths, and sampling rates. However, USB controllers and protocol overhead can limit audio quality compared to dedicated multichannel interfaces like S/PDIF. Latency may also be higher on USB audio output depending on the device hardware and drivers.

Alternatives for audio output

There are several alternative options for audio output from computers and devices besides directly using a USB port, with the most common being:

3.5mm headphone jack

This analog audio output port is nearly universal on computers, mobile devices, TVs, and audio gear. Also referred to as a headphone output or aux output, it allows connecting headphones, speakers, or other analog audio equipment using a 3.5mm audio cable (source). While very convenient, the audio quality is limited since the port carries an analog stereo signal.

HDMI

HDMI ports can carry high-resolution multichannel digital audio alongside video signals, allowing connecting the device directly to an audio video receiver (AVR) for output to a home theater system (source). HDMI offers higher audio fidelity than the basic 3.5mm output.

Bluetooth/wireless

Bluetooth and other wireless protocols like WiFi allow transmitting audio wirelessly to compatible devices such as speakers and headphones, providing exceptional convenience of use and the ability to move freely while listening. However, wireless audio does have some limitations like lower fidelity, latency, interference, and battery requirements to consider.

USB audio adapters

USB to 3.5mm audio jack adapters, also called USB sound cards, allow you to connect headphones or speakers to a USB port to output audio. Popular options like the UGREEN USB to Audio Jack Sound Card Adapter plug into a USB-A port and provide a 3.5mm audio jack to connect analog headphones or speakers.

HDMI to USB audio extractors can extract the audio signal from an HDMI source like a Blu-ray player, game console, or computer and output it to a USB port. This allows you to connect headphones or speakers via a USB to 3.5mm audio adapter. HDMI audio extractors may require additional power if the HDMI source doesn’t provide enough power over USB.

Benefits of USB audio adapters include:

Easy plug and play connectivity without needing to open up your computer
Portability to use your headphones or speakers with multiple devices

Provide an audio output option if your device lacks a 3.5mm audio jack

Limitations include:

Audio quality depends on the digital-to-analog converter (DAC) quality

May need to reconfigure audio output device settings in your operating system
Occupies a USB port instead of a dedicated audio jack

USB DACs

A USB DAC (digital-to-analog converter) is a device that converts digital audio signals into analog signals for playback through headphones or speakers. Unlike sound cards built into computers and other devices, USB DACs offer improved audio quality by taking the digital-to-analog conversion process outside of noisy computer environments.

Compared to onboard sound cards, USB DACs provide cleaner audio signals with lower noise and distortion levels. By bypassing the DAC built into a computer or smartphone, the conversion is handled more efficiently for studio-quality sound. USB DACs also support high-resolution formats like DSD and 32-bit/384kHz PCM that most sound cards don’t.

High-end USB DAC models contain sophisticated components like ES9038Q2M decoder chips to ensure accurate conversions. Some USB DAC/amp combos also have dedicated headphone amplifiers to properly drive headphones across various impedances.

In summary, USB DACs lead to substantial audio quality improvements over basic sound cards by specializing in clean, accurate digital-to-analog conversion of lossless digital audio files and streams.

Software playback options

To play audio over a USB port, you’ll need media player software that supports USB audio output. Popular options include: Plex, VLC media player, USB Audio Player, and more. These players can directly output audio over USB when the appropriate drivers are installed.

For Windows users, outputting audio over USB typically requires having the standard USB Audio Device Class drivers installed. Mac and Linux systems generally have USB audio support built-in without extra drivers needed. On Android, specific USB audio apps may require the Android Open Accessory mode to be enabled.

USB audio playback can achieve high quality, with support for high resolution formats like DSD, DXD, 24-bit/192kHz audio in top players like USB Audio Player. Of course, the audio quality depends on the digital-to-analog conversion of the USB device – ports or USB DACs will have varying bit depths and sampling rates.

Audio quality considerations

While using USB ports for audio output has several advantages, there are some limitations to be aware of in terms of audio quality:

Limitations of USB audio

USB ports and audio have bandwidth limitations that can impact audio quality. For example, a USB 2.0 port only supports up to 24-bit/192 kHz, while USB 3.0 supports up to 32-bit/384 kHz (Is USB or 3.5mm Better for Audio?). Higher bitrates and sampling rates can enable richer, more detailed sound.

Interference issues

The digital USB connection can sometimes pick up electromagnetic interference from other components inside a computer. This can introduce static, clicks, pops, or distortion into the audio signal (Is a USB better than a 3.5mm audio jack?). Using shielded USB cables may help reduce interference.

Bitrate/sampling rate limitations

While USB audio supports high resolution audio, the bitrate is still limited compared to other dedicated digital audio connections. For example, S/PDIF connections can support Lossless audio with virtually unlimited bitrate and sampling rate. By comparison, even USB 3.0 tops out at 32-bit/384 kHz (USB vs 3.5mm which one is better?). For high-end audiophile listening, this can impact sound quality.

Application examples

Using a USB port for audio output opens up many possibilities to connect audio devices. Here are some common application examples:

Headphones, speakers, and soundbars

One of the most common uses is to connect headphones, computer speakers, or soundbars to the USB port to play audio from a computer or device. This allows you to bypass the built-in audio hardware and use an external USB digital-to-analog converter (DAC) for improved audio quality.

For example, you can connect powered USB speakers to a laptop’s USB-A port to use as external speakers instead of the built-in speakers (1). Or you can connect high-end audiophile headphones to a USB DAC to get superior sound from your computer (2).

USB microphones

Many USB microphones connect via USB-A or USB-C ports. This allows direct connection to a computer for recording podcasts, music, voiceovers and more. The audio signal gets converted directly into digital instead of using the computer’s built-in audio interface (3).

DJ equipment

DJ controllers, mixers, and other equipment often support USB audio connectivity. This allows DJs to connect their gear directly to a laptop for software control and playback. For example, the Pioneer DDJ-200 DJ controller can connect via USB to output the master mix audio and route headphone cue signals from DJ software like Serato or Traktor (4).

Troubleshooting Tips

If you run into issues using a USB port for audio output, there are some troubleshooting steps you can try:

Driver Updates

Make sure you have the latest USB audio drivers installed for your device. Check the manufacturer’s website for any available driver updates. You can also try reinstalling the drivers or using the basic USB audio class driver included with Windows.

Configuring Sound Settings

Check your sound control panel to make sure your USB device is set as the default output device. Make sure levels are turned up for the device and it is not muted or disabled. If you have multiple sound devices, try setting the USB device as the default device.

Hardware and Cable Issues

Try using a different USB port or cable. Make sure the USB cable is fully connected at both ends – the device and the computer. Rule out any conflicts with USB hubs by trying a direct USB port connection. Check for any damage, bent pins or other physical issues with USB ports that could cause connectivity problems.

Summary

USB ports can be used as audio outputs, but require some additional hardware or software to convert the digital USB data into an analog audio signal. While convenient, USB audio has some limitations in audio quality compared to dedicated sound cards or external DACs.

Some best practices when using USB for audio output:

Use a USB audio adapter or external USB DAC to handle the digital-to-analog conversion and amplify the signal for your headphones or speakers.
Check that your operating system, drivers, and audio playback software support USB audio output.
Watch your volume levels, as USB audio may have lower power output than headphone jacks on laptops or sound cards.

Use high quality, shielded USB cables to avoid interference or signal quality issues.
For critical listening applications, consider a dedicated external DAC and amplifier setup instead of relying only on USB audio.

While convenient, USB has limitations for serious audiophile use. But for more casual listening applications, with the right adapters, USB ports can work reasonably well for audio output from a computer.