Automatically Connecting Bluetooth Headset with LDAC Codec: Make PipeWire Use It

Introduction

In this article, we will discuss how to automatically connect a Bluetooth headset to a PC and ensure that the LDAC codec is used instead of the default HSP/HFP codec, which often results in poor sound quality. We will cover the necessary steps and concepts required to make this work using PipeWire, a modern audio routing framework.

Prerequisites

• A Linux-based operating system with PipeWire installed
• A Bluetooth headset that supports the LDAC codec

Understanding PipeWire and Bluetooth Codecs

PipeWire is a modern audio routing framework that aims to replace the older PulseAudio and JACK frameworks. It provides a simple and efficient way to route audio between different applications and hardware devices, including Bluetooth headsets. By default, PipeWire chooses the HSP/HFP codec when connecting a Bluetooth headset, which often results in poor sound quality.

The LDAC codec is a high-quality audio codec developed by Sony that supports up to 990 kbps bitrate and 24-bit/96 kHz audio. It is a popular choice for wireless audio devices, including Bluetooth headsets.

Configuring PipeWire to Use LDAC Codec

To configure PipeWire to use the LDAC codec when connecting a Bluetooth headset, we need to create a configuration file that specifies the desired codec. Here's how to do it:

Step 1: Create a Configuration File

Create a new file called ~/.config/pipewire/media-session.d/bluetooth-ldac.conf with the following contents:

[General]
options.bluez5.transport = "le"

[Mapping bluetooth.headset_head_unit]
driver = "bluez5"
nodes = "alsa_output.bluez_source.XX_XX_XX_XX_XX_XX.monitor"
properties = {
    device.description = "My Bluetooth Headset"
    device.icon_name = "audio-headphones"
    device.api = "bluez"
    device.class = "headset_head_unit"
    device.string = "XX:XX:XX:XX:XX:XX"
    device.intended_roles = "headset"
    device.form_factor = "headset"
    device.bluez.capabilities = "headset,head_unit,a2dp,avrcp"
    device.bluez.codec = "ldac"
}

Replace XX:XX:XX:XX:XX:XX with your Bluetooth headset's MAC address.

Step 2: Restart PipeWire

Restart PipeWire by running the following command:

systemctl --user restart pipewire pipewire-pulse

Step 3: Connect Bluetooth Headset

Connect your Bluetooth headset to your PC. PipeWire should now use the LDAC codec instead of the default HSP/HFP codec.

In this article, we discussed how to configure PipeWire to use the LDAC codec when connecting a Bluetooth headset to a Linux-based operating system. By creating a configuration file that specifies the desired codec, we can ensure that our Bluetooth headset uses a high-quality audio codec instead of the default HSP/HFP codec, which often results in poor sound quality.

References

• PipeWire
• LDAC Codec
• PipeWire on Arch Linux