NL Series -FT Option


Enable Fast-Fourier-Transform analysis with any NL Series Meter

The -FT option enables FFT (Fast-Fourier-Transform) analysis with a resolution of 8000 spectrum lines and a maximum zoom of x40. Recorded FFT graphs can be saved to the unit's SD card for analysis at a later date.

Main channel

Allows the simultaneous measurement of the following items, using a selected time weighting and frequency weighting.

  • Instantaneous sound pressure level Lp
  • Equivalent continuous sound pressure level Leq
  • Maximum sound pressure level Lmax

FFT analysis

Allows the simultaneous measurement of the following items, by performing analysis of each frame (400 ms) using the selected frequency weighting (see page 18). Overlapping rate is fixed to 0 % (cannot be changed).

  • Spectrum of 1 frame INST
  • Power average of Spectrum LIN
  • Maximum of Spectrum MAX

The -EX option is required to be installed before the NX-42FT