SLM 109 Specification


​IEC 61672 Class 1, IEC 60651 Class 1, and IEC 60804 Class 1

ANSI S 1.4 Class 1 and ANSI S 1.43 Class 1

​Measurement range

​30 dB to 130 dB (Expandable to 160 db by using a ¼ inch microphone) Dynamic range of 100 dB

​Accuracy and resolution

​Accuracy of ± 1.0 dB Resolution of 0.1 dB

​Frequency range

​10 Hz – 20 kHz

​Measurement functions

​Sound Pressure Level (SPL), LEQ, LN, PEAK, MAX, MIN, RMS, SD Simultaneous measurement of three profiles with independent sets of filters and detector time constants

​Frequency weighting

​A, C, Z – can be measured in parallel

​Time Weighting

​Fast, Slow, Impulse – can be measured in parallel

​Integration time

​Programmable (1s to 24h)

​Octave filter

​1/1 octave at 5 points of frequency: 31.5 Hz, 63 Hz, 125 Hz, 250 Hz, 500 Hz

​Sampling frequency

​48 kHz

​LCD display

​160x160 mm LCD, with backlight. Can display the measurement with 0.1 dB resolution

​Analysis rate

​64 times per second


​Inbuilt 4GB storage through a Micro SD card

​Export data

​Use adapter (Micro SD to SD card sets), or directly connect the computer to read the memory card data files; RS 232 interface

​Post processing software

​Comes with a processing software to read the stored data and generate reports


​Adjustable over 30-130dB range. The power light will turn red when the measurement value is larger than or equal to the alarm value set


​In built timer with current date and time displayed on the main screen. Also has an auto-power off mode that can be set manually


​4*1.5V AA alkaline batteries, sustainable use of more than 18 hours. Includes a low battery indicator. Rechargeable battery option available It can also run on an external 7-14V DC power adapter


​Auto calibration using 94 dB and 114 dB external calibrators


​300 x 70 x 36 mm


​About 620g, including batteries

​Standard accessories

​Carrying case and windscreen (included) Calibrator, tripod stand and spare microphone (available separately)


​One year