DBMix is a software DJ mixing system for digital audio. DBMix allows a user to output multiple simultaneous audio streams on a single sound device, and to transform/modify each stream independently. There are five main components to DBMix:

1. Fourier Synthesis Daemon - this is a daemon application
   that handles adding multiple data streams into a single data stream for
   output, allowing you to play multiple songs simultaneously with a single
   soundcard. Each data input stream to the fourier synthesis daemon is refered to as a "channel", because this is the name given to each input to an analog DJ Mixer.
   
2. Clients - responsible for creating input to the system, and writing the data to a dbfsd channel. Example generators are xmms, mpg123, and sox.
   
3. DBAudiolib - this is the client interface API to dbmix.
   It provides transparent format conversion and pitch/speed control.
   
4. Mixer - the mixer is the user interface to the DBMix system. It allows a single interface to control all input channels. An example of a mixer is the DBMixer application. DBMixer allows the user to mute, change volume, cue, and crossfade inputs
   
5. Peripherals - hardware devices that you can use
   to control aspects of dbmix. See the section on exmixer below for and
   example.
   

Features:

• Output multiple audio channels (up to 8 inputs) using a single sound device
  
• Cueing support using multiple soundcards. (ability to have one sound device used for a master output, and a second sound device for headphones)
  
• Cueing support using a single soundcard.
  
• Supports the standard digital audio format of 16bit signed data at 44.1 KHz
  
• Use of the Open Sound System for sound device control
  
• Session recording to a wav file (controlled by the dbmixer options menu)
  
• A single DJ Mixer style GUI interface for controlling DBMix channels.
  
• Independent channel controls: volume/gain/level, pitch/speed control +/-
  10%mute, cue, and pause.
  
• IPC layer to allow the mixer to control the play/pause/stop/etc of dbmix client programs.
  
• Crossfader
  
• Punch buttons (allows you to add in the muted crossfader input. Handy
  for popping in sound bytes)
  
• Control of master and cue soundcard mixers
  
• Swap master and cue soundcards on the fly
  
• Autofade buttons with fade speed control
  
• L/R Balance control
  
• Clipping notification
  
• The mixer is optionally controled by an external device. See section
  titled Exmixer.
  
• Digital Sampler with start/end editing abilities, and Load/Save samples
  
• Beat matching synchronization tools (sorry no UI yet)
  
• Multiple client support: xmms output
  plugin, mpg123, dbcat, HREF="http://www-stud.fht-esslingen.de/~alkoit00/tX">terminatorX, gqmpeg
  (Note: to use gqmpeg, openthe preferences dialog, choose the Output tab, and
  enter "-s" in the User options field to enable output to stdout. To launch
  gqmpeg, type "gqmpeg | dbcat &" at the command prompt)
  
• speed/pitch control.
  
• format conversion from:
  
• 8 bit signed mono and stereo data
  
• 8 bit unsigned mono and stereo data
  
• 16 bit signed mono and stereo data
  

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