Organ structure and components

This chapter describes the physical structure of the BIG ORGAN: its size, frame, pipe families, bellows, wind chests, and percussion.
It serves as a reference for all mechanical and acoustic subsystems.

Project type

Instrument

Bellows and motor

Design notes for the microwave‑sized bellows and motor assembly.
Includes airflow targets, pressure goals, and mounting considerations

Frame construction

Describes the framework added to the golf cart to support pipes, wind chests, bellows, electronics, and percussion.
Includes mounting points, materials, and structural bracing.

Organ size and layout

Defines the overall footprint of the organ as mounted on a golf cart.
Includes height, width, depth, and constraints such as visibility, weight distribution, and transport clearances.

Other voices

Let's talk about incorporating other instruments to compliment the melody and counter melody ranks, such as the glockenspiel.

Percussion

Overview of percussion elements integrated into the organ, including drums and additional percussive instruments.
Focuses on mounting, actuation, and balance with the pipe sound.

Additional percussion elements

Other percussive instruments (e.g., bells, blocks, shakers).
Notes on placement, triggering, and integration with the main organ sound.

Drums

Drum selection, mounting methods, and actuation mechanisms.
Includes considerations for volume control and mechanical noise.

Pipe families

Overview of all pipe groups used in the organ: bass, accompaniment, main melody, and counter‑melody.
Each family has its own scaling, voicing, and wind requirements.

Accompaniment pipes, two ranks

Details for both accompaniment ranks, including tonal role, scaling, and wind needs.
Notes on blending with main melody and bass.

Bass pipes

Specifications and layout for the bass pipe set.
Includes scale, materials, and placement for optimal low‑frequency projection.

Counter melody pipes, three kinds

Information on the counter‑melody ranks and how they interact with the main melody.
Focus on contrast, register, and articulation.

Melody pipes, four to five different kinds

Description of the primary melody ranks and their intended character.
Includes considerations for brightness, attack, and tuning stability.

Wind chests

Overview of the three wind chests and their pipe assignments: main melody, bass & accompaniment, and counter‑melody.
Describes general valve logic and air distribution.

Bass and accompaniment wind chest

Let's consider a combined wind chest design serving both bass and accompaniment ranks.
Notes on balancing pressure and avoiding crosstalk.

Counter melody wind chest

Wind chest design dedicated to counter‑melody ranks.
Focus on responsiveness and isolation from other chests.

Main melody wind chest

Layout and valve logic for the main melody pipes.
Includes channel routing, pallet design, and connection to the bellows.

Big organ build