Our recently released SMAART® Control in FIR Designer (& FIR Designer M) includes support for the “moving mic measurement” method. This method is often used as an efficient way to take a spatially averaged measurement with a single microphone, rather than averaging the response of multiple microphones at fixed positions.
To use this method, follow these steps:
- In SMAART, choose a spectrum or transfer function measurement & set its Averaging to infinite (Inf).
- In FIR Designer, open the SMAART Control dialog & enable live streaming of the measurement to the SMAART Streaming plot.
- Set the “Reset delay” to the time it takes to walk from the computer (running FIR Designer) to the measurement position.
- Check “Auto grab” and set the “Grab delay” to the measurement averaging time. (This is the length of time SMAART will be averaging the microphone response before the measurement is captured.)
- To take a measurement, select “Reset Average,” then walk to the measurement position and begin moving or waving the microphone around. After the Reset delay + Grab delay time, the grabbed measurement will appear in the Grabbed measurement list.
- Any measurement in the list can then be selected & transferred with one-click to FIR Designer’s ‘Import’ tab for use in FIR Designer’s workflow.
There are several articles available online which explore this method in more detail, including the AES Paper “Moving Microphone Measurements for Room Response in Cinema” by Paul Peace (Community Professional Loudspeakers), Shawn Nageli (Harman International) and Charles Sprinkle (NXC Systems). (The link will require an AES login.)
FIR Designer is compatible with a wide range of loudspeaker measurement tools in addition to SMAART. See all supported import file formats.
SMAART is a registered trademark of Rational Acoustics LLC, Connecticut, USA.