Theatre Pipe Organ Consoles have long been recognized as one of the most intricate human to machine interface system ever devised.

1. Manuals:

The keyboards are called manuals.
There are four for the hands & pedalboard which is played with the feet. Each manual has a name. From the bottom to the top they are called the: Accompaniment, Great, Bombard, and Solo manuals.
Each manual can play virtually any sound the organ can make.

2. Stop Tabs:

These colorful tabs control which sounds are played by each manual.
The color coding is consistent.
White is for flue pipes (such as the flute) & percussions.
Red is for reed pipes (such as the clarinet).
Yellow is for string & Celeste instruments (such as the violin).
Black is for the couplers that are able to combine manuals together or combine scales of instruments together.

3. Combination Pistons:

These are the small white buttons under the manuals & the nickel toe studs on the pedalboard. They allow the performer to set up their various combinations of stops and then assign that collection of sounds to a specific button (piston). Pressing that piston during a performance recalls all of the stop tabs that were assigned to that piston.
Pistons can be “Divisional” controlling only that manual, or they can be “General” controlling the entire organ.
Combination Pistons are really necessary for an organ of this size.

4. Swell Shoes:

These are the black rocking pedals behind the pedalboard which are used to control the volume of the organ.
The left swell shoe controls the volume and expression for the two pianos.
The middle three swell shoes control the six sets of wooded shutters up on the wall. These shutters are called Swell Shades. Swell shades open and close with the respective motions of the swell shoes.
Pipes and percussions of the organ are either “on” or they are “off”.
Volume is controlled by the amount of the opening of the swell shades.
The right swell shoe is the Crescendo pedal. As it is depressed, more and more progressively louder stops are brought into play.

5. Second Touch:

The lower two manuals (Accompaniment & Great) have a feature known as Second Touch (2nd Touch). This is an adaptation used almost exclusively on theatre pipe organs which allows a second set of stop tabs to be assigned to the manual. This grouping of stop tabs is played by pressing the keys, with more pressure, down past the main set of contacts into a lower “second” set of contacts. In this manner, a skilled performer can play the accompaniment and also accent chords or melodies on the same manual with the same hand.