From Left: Power Supply, Control bus, Sound card bus containing all the digitally recorded pipe notes (‘digital pipes’) in memory; audio generation bus (generates audio signals to be amplified to the speakers).
Below the shelf are the two 6-channel amplifiers that drive the speakers. The speakers here are for configuration and testing purposes only; once configured the actual speakers are hooked up for testing.
Attached underneath the shelf above the amplifier on the right is the reverberation box which performs “spatial” adjustments to the source of the sound, allowing, say, a ranks of pipes to be heard as if each note comes from its own position in the rank.
Of course, due to the required acoustic matching to the sanctuary all final acoustical adjustments can only be completed upon installation on site.