Sound

Before reading this article, it is recommended to read the previous one: Audio over Bluetooth: most detailed information about profiles, codecs, and devices / по-русски

Some wireless headphone users note low sound quality and lack of high frequencies when using the standard Bluetooth SBC codec, which is supported by all headphones and other Bluetooth audio devices. A common recommendation to get better sound quality is to buy devices and headphones with aptX or LDAC codecs support. These codecs require licensing fees, that's why devices with them are more expensive.

It turns out that the low quality of SBC is caused by artificial limitations of all current Bluetooth stacks and headphones' configuration, and this limitation can be circumvented on any existing device with software modification only.

This article is also available in Russian / Эта статья также доступна на русском языке

The mass market of smartphones without the 3.5 mm audio jack changed headphones industry, wireless Bluetooth headphones have become the main way to listen to music and communicate in headset mode for many users.
Bluetooth device manufacturers rarely disclose detailed product specifications, and Bluetooth audio articles on the Internet are contradictory and sometimes incorrect. They do not tell about all the features, and often publish the same false information.
Let's try to understand the protocol, the capabilities of Bluetooth stacks, headphones and speakers, Bluetooth codecs for music and speech, find out what affects the quality of the transmitted audio and the delay, learn how to capture and decode information about supported codecs and other device features.

TL;DR:

• SBC codec is OK
• Headphones have their own per-codec equalizer and post processing configuration
• aptX is not as good as the advertisements say
• LDAC is a marketing fluff
• Voice audio quality is still low
• Browsers are able to execute audio encoders compiled to WebAssembly from C using emscripten, and they won't even lag.

Pathfinder: Kingmaker (PF:K for short) is a role-playing video game created by Owlcat Games, released in Fall 2018 on Steam and GoG. Inspired by classic Bioware games, this project uses a popular board game system ruleset, combat takes place in Real-Time with Pause, follows an isometric camera, and has a non-linear story with multiple unique endings.

In this article, I will share a little about how we worked on designing the audio throughout the game’s development including task management, the search for inspiration, and troubleshooting. An experienced specialist may not find anything particularly groundbreaking in this recap, but beginners and enthusiasts will definitely discover some points of interest.

Known now as a «motherboard speaker», or just «beeper», PC Speaker has been introduced in 1981 along with the first personal IBM computer. Being a successor of the big serious computers for serious business, it has been designed to produce very basic system beeps, so it never really had a chance to shine bright as a music device in numerous entertainment programs of the emerging home market. Overshadowed by much more advanced sound chips of popular home game systems, quickly replaced with powerful sound cards, it mostly served as a fallback option, playing severely downgraded content of better sound hardware.

«System Beeps» is a music album in shape of an MS-DOS program that features original music composed for PC Speaker using the same basic old techniques like ones found in classic PC games. It follows the usual retro computing demoscene formula — take something rusty and obsolete, and push it to eleven — and attempts to reveal the long hidden potential of this humble little sound device. You can hear it in action and form an opinion on how successful this attempt was at Bandcamp, or in the video below. The following article is an in-depth overview of the original PC Speaker capabilities and making of the project, for those who would like to know more.