text: Surround sound On most digital organs, several audio channels are used to create a more spacious sound. Higher-quality digital organ builders use custom audio and speaker systems and may provide from 8 to 32 or more independent channels of audio, depending on the size of the organ and the budget for the instrument. With dedicated high-power subwoofers for the lowest frequencies, digital organs can approach the physical sensation of a pipe organ.
  Pipe organ simulations
  To better simulate pipe organs, some digital organs emulate changes of windchest pressure caused by the air pressure dropping slightly when many notes are sounding simultaneously, which changes the sound of all the pipes.
  Digital organs may also incorporate simulated models of swell boxes which mimic the environmental effects on pipes, pipe chest valve release, and other pipe organ characteristics. These effects can be included in the sound of modern digital organs to create more realistic pipe organ tone.
  Digital pipe sound can include sampled or modeled room acoustics. Rodgers uses binaural and crosstalk cancellation processing to create real-time acoustic models, and Allen also uses room acoustics as part of the sound generation.
  (1990s–)
  The data processing power of PCs has made personal organs more affordable. Software applications can store digital pipe sound samples and combine them in real time in response to input from one or more MIDI controllers. These tools can be used to assemble home-built organs that can rival the sound quality of commercially built digital organs at a relatively low cost.
  In churches