USB Audio Output on Android

USB audio output allows Android devices to output audio directly to external USB digital-to-analog converters (DACs), amplifiers or USB speakers, bypassing the onboard DAC and amplifier. This allows the playback of high-resolution audio formats like FLAC that may not be supported by the device’s internal DAC. It also provides the ability to leverage superior DACs and amplifiers compared to those built into smartphones and tablets for improved audio quality. The availability and implementation of USB audio output varies across Android devices and versions. Certain conditions need to be met to enable and successfully use USB audio output.

USB Audio vs Headphone Jack

The key difference between USB audio and a traditional headphone jack is how the audio signal is transmitted. A standard 3.5mm headphone jack outputs analog audio directly to your headphones or speakers. This means there is no digital-to-analog conversion taking place – it is an analog end-to-end connection.

In contrast, USB audio first converts the digital audio data to an analog signal before sending it to your headphones. This conversion is handled either by the USB host device (e.g. your phone) or an external USB audio adapter. While analog audio can theoretically have unlimited resolution, digital-to-analog conversion may result in some loss of fidelity compared to a direct analog source (

However, USB audio has the potential for higher quality audio reproduction compared to analog connections, as digital transmission is less susceptible to interference. The maximum quality depends on the digital sample rate and bit depth, which can be far higher over a digital USB connection (Simply Headsets).

USB Audio Adapter Support

USB audio support was first introduced in Android 3.1 and has continued to expand across Android versions.

Android 4.1 and higher support USB audio peripherals like headsets, microphones, and speakers in USB device mode. This allows audio output directly through a connected USB device without the need for a headphone jack (source: https://source.android.com/docs/core/audio/usb).

Later versions of Android also allow the phone to act as a USB host for audio input and output. Android 5.0+ can function as a USB digital audio source to output audio over USB to an external USB DAC or amplifier (source: https://www.quora.com/How-do-I-get-all-audio-out-through-a-USB-on-Android).

Overall, most modern versions of Android from 4.1 and up have some level of support for USB audio adapters, with the capability improving across versions. But there can be device-specific limitations, so compatibility ultimately depends on the Android phone model and manufacturer implementation.

Enabling USB Audio Output

To enable USB audio output on Android devices, you need to go into your phone’s settings and configure the USB connection. Here are the general steps:

1. Connect your USB audio device (DAC, external sound card, etc.) to your Android phone using an OTG cable or adapter.

2. Go to Settings > Connected Devices > USB. You may also find this under a section called “Connections.”

3. Under “Use USB for,” select “Audio source.” This enables your phone to output audio through the USB port.

4. You may need to select the option to “Detect USB device” if your phone doesn’t automatically recognize the connected USB audio device.

5. Some phones will prompt you to “Allow USB debugging” for security purposes. Check this box to enable audio output.

6. Once enabled, all audio should now route through your external USB audio device when headphones or aux cables are connected to it.

Note that steps may vary across Android manufacturers like Samsung, LG, Motorola, etc. Refer to your device guide for exact menu options.

According to this Android Stack Exchange thread, Android 9 (Pie) and above has native support for USB audio output in Settings.

Compatible USB Audio Devices

Most USB audio devices that adhere to the USB Audio Device Class specifications should work with Android devices that support USB host mode and USB audio (source: https://source.android.com/docs/core/audio/usb). This includes USB DACs (digital-to-analog converters), USB sound cards, and USB audio interfaces. Some common types of compatible USB audio devices include:

• External USB DACs – Small USB stick-like devices that can provide cleaner analog audio output than a phone’s internal DAC.
• USB sound cards – Offer audio input and output, sometimes with headphone amplifiers for driving high-impedance headphones.
• Audio interfaces – For connecting instruments, microphones, and studio monitors. Often include MIDI and multichannel capabilities.
• USB microphones – Make recording direct to a phone or tablet easy.

Android is compatible with USB audio devices that support USB modes like USB Audio Device Class 2.0 and USB Audio Class 2.0 (source: https://www.reddit.com/r/AudioPost/comments/s9nqg6/lets_talk_using_audio_interfaces_on_android/). However, some USB audio devices may not be fully compatible due to driver or hardware limitations.

USB Audio Quality

There has been some debate around whether USB audio output offers the same level of sound quality as a traditional headphone jack on Android devices. According to testing done on the Audiophile Style forums, Android 10 does provide high-quality digital audio output over USB that is comparable to the built-in headphone jack.

In their testing, users found no detectable difference in audio quality between the headphone jack output and USB audio output when using high-quality headphones and DACs (digital-to-analog converters). Measurements indicated equally low noise floors and distortion on both outputs (Source). This suggests that Android’s USB audio support can deliver bit-perfect digital audio just like the headphone jack.

That said, some factors like the specific USB controller and DAC being used can still impact quality. But overall, Android’s USB audio implementation does not appear to degrade or limit sound quality versus the traditional 3.5mm jack. Users looking for audiophile-level sound can utilize USB audio output on Android 10 and higher without quality loss compared to the headphone jack output.

Latency

Latency refers to the time it takes for audio output to be heard after an audio signal is sent from an app. With USB audio devices, latency can be an issue due to the USB transfer and audio processing time. According to Android’s developer documentation, audio output latency for the headphone jack is typically around 10-150 ms. However, for USB audio devices, latency is often higher.

As explained by Superpowered, USB audio interfaces add around 1-6 ms of latency on top of the baseline headphone jack latency. This is due to the time required for audio data transfer over USB. With unofficial USB drivers or slow USB bus settings, this latency penalty can be even higher.

For professional audio applications that require low latency like musical instruments or recording, the extra latency from USB can be an issue. According to users on Reddit, USB audio latency on recent Android versions can be up to 100 ms, compared to around 10 ms for the headphone jack. However, for most consumer playback use cases, the slightly higher latency of USB audio will not be noticeable.

Power Considerations

USB audio devices can draw significant power from a mobile device’s battery, which is an important consideration when using USB audio output. The maximum power draw for USB audio devices connected to an Android phone or tablet is 100mA per USB port according to the Android Stack Exchange. This is much lower than the 500mA that high-quality USB audio interfaces are designed to consume when connected to a computer.

To help reduce battery drain, try to avoid using power-hungry USB devices like mixers, multi-input interfaces, or devices with LED meters and displays. Simple USB DACs (digital-to-analog converters) and basic headsets generally have lower power requirements. Also, use a short, high-quality USB cable to minimize power loss through the cable.

Keep an eye on your device’s battery level when using USB audio and reduce screen brightness or turn off other radios like WiFi/Bluetooth to help conserve power if needed. External battery packs are another option for longer recording or playback sessions.

Apps with USB Audio Support

A number of popular media apps have added support for USB audio output on Android devices. This allows you to bypass the internal DAC of your phone and take advantage of an external USB DAC for improved audio quality. Some apps that support USB audio output include:

USB Audio Player PRO – A high quality music player designed specifically for use with external USB DACs. It supports all resolutions and sample rates.

Poweramp – A feature-rich music player that has an option in settings to enable USB audio output.

VLC Media Player – The popular open source media player has support for USB audio output across all platforms.

Plex – The Plex media server app allows USB audio output when playing media from your Plex library.

Neutron Music Player – An advanced music player with native support for USB audio output. Has options for bit-perfect output.

To take advantage of USB audio support in these apps, you need to have a compatible USB DAC connected to your device. The apps route audio through the external DAC rather than the phone’s internal audio hardware when USB output is enabled. This allows you to enjoy improved audio fidelity.

Tips for Using USB Audio

Here are some tips for getting the best audio experience when using USB audio output on Android:

Use a high-quality USB DAC (digital-to-analog converter). The DAC built into your USB adapter or cable can greatly impact audio quality. Look for USB DACs that support 24-bit/192 kHz for the best resolution ¹.

Avoid cheap USB-C adapters or cables, as they often have poor DACs. Stick to reputable brands designed for audio ².

Check that your USB audio device supports UAC 1 or UAC 2 standards. These allow direct high-quality output rather than more limited USB audio class support.

Use an OTG (On-The-Go) adapter if your USB port doesn’t support audio out directly. OTG adapters add this ability.

Consider an external USB DAC/amp if you need additional amplification. The USB port itself provides limited power.

Experiment with audio apps that have USB audio support, like UAPP or Neutron, for advanced audio controls.

Disable audio effects or enhancements in your music apps, as these can diminish quality over USB.

Adjust Android’s Developer Options settings like “Disable USB audio routing”, “Force USB audio” or “USB host fix” if you encounter issues.