Delphi-BASS

FMXAudio

FMX Audio BASS Lib for Win, Android, Linux

Delphi ASIO & VST Project

. [Delphi] Framework for writing applications using the ASIO interface and VST plugins. It comes with countless DSP algorithms all demonstrated in dozens of examples. // Not very active lately, but the trunk is in a usable state

Audorra

. [Delphi] [FPC] Digital audio library for Delphi and Freepascal. Using a flexible plugin architecture, it allows you to exchange the audio backend (e.g. WaveOut, OpenAL), add protocol classes (e.g. file, http) and decoders

NewAC - New Audio Components

(abandoned, list of forks on GH here). [Delphi] Designed to help your Delphi programs perform different sound processing tasks. With NewAC you can play audio stored in many formats (wav, Ogg Vorbis, FLAC, Monkey Audio, WavPack, MP3, Windows WMA, DTS, AC-3 (Dolby Surround), VOB (DVD files)). // Playback, recording, tag read/write, some audio editing tasks and conversions