Designing an anechoic chamber starts by setting the acoustic targets: the free field frequency range, the noise floor, the free field deviation and the standard the room must satisfy. These targets drive every choice that follows, including the absorber structure, the room size and the isolation scheme.
The absorptive structure is the heart of the chamber. Wedges follow quarter wavelength theory, and their length sets how well the room absorbs low frequencies, while a flat panel structure reaches a similar result with far less depth. Whichever is used, the material has to be eco friendly, fire retardant and stable in its absorption over the long term.
Isolation from both airborne noise and vibration matters just as much. A multi layer isolating shell keeps outside noise at the door, while a floating floor and spring isolators cut off vibration coming through the foundation. Doors, windows, vents and the points where cables pass through the wall are the weak spots most likely to leak, so they need dedicated sealing and silencing. Get all of these right and the result is a chamber that genuinely meets its figures.