There is a familiar sequence to a private cinema project that goes wrong. The equipment is chosen first, because equipment is the part that can be researched, compared and admired. The room is dealt with afterwards, because the room is assumed to be a container.
It is not a container. It is the last and largest component in the signal path.
The room is in the signal path
Everything a loudspeaker produces reaches the listener twice: once directly, and then again as the room returns it — off the walls, the ceiling, the floor, the glass, the seating. In a small room those reflections arrive very quickly, close enough behind the direct sound to blur it rather than accompany it.
No processor removes that. Room correction can flatten a response curve at a measurement position; it cannot shorten a decay time, and it cannot uncouple a wall that is resonating. Those are construction problems, and construction problems have to be solved while there is still construction happening.
What has to be decided early
A short list, all of which are structural rather than electronic:
- the internal dimensions of the finished room, and their ratios
- the build-up of walls and ceiling, and how they are isolated from the structure
- where absorption sits, and where it deliberately does not
- how the low frequencies will be controlled, which usually means volume given up to treatment
- the seating positions, because they decide where the room has to behave
Each of those changes the drawing. Each of them is cheap on a drawing and expensive once the plaster is on.
The consequence for the equipment list
When the room is resolved first, the equipment list gets shorter and better, not longer. A room that is quiet, sealed and controlled asks less of the amplification and less of the processing. Money that would have gone into compensating for the room goes into the parts you actually hear.
When the room is resolved last, the opposite happens: the specification grows to cover for the space, and the result is a system that measures respectably and never quite convinces.
The order, stated plainly
Design the room. Engineer the technology to the room. Build and install. Then calibrate.
Each stage feeds the next, and the sequence only runs in one direction.