How to Calibrate Sound Level on the C-DSM1 Sound Level Meter

Calibration is an essential task to ensure your sound level meter is collecting accurate and repeatable results. Performing calibration for the C-DSM1 takes less than five minutes, which is perfect if your time is at a premium!.

Figure 1 Watch an Instrument Choice Scientist demonstrate how to calibrate C-DSM1 Sound Level Meter here.

How to Calibrate the C-DSM1 Sound Level Meter

To perform a calibration, you will need;

• The C-DSM1 Sound Level Meter;
• A Sound Level Calibrator suitable for class 2 meters. For the video above we used the CEL-120/2;
• A small screwdriver.

1. Turn the C-DSM1 on by pressing the ON/OFF button.
2. Select the following functions;
   1. A-Weighting (dBa) – Press the ‘A/C’ button until ‘dBa’ appears on the LCD screen.
   2. HI – Press the HI/LO button until ‘HI’ appears on the LCD screen.
   3. Fast (F) – Press the ‘F/S’ button until ‘FAST’ appears on the LCD screen.
   4. Ensure the MAX function is off.
   5. Ensure the HOLD function is off.
3. Open the rear battery cover using a screwdriver and carefully take the battery out of the meter while keeping plugged in. After removing the battery from the compartment, two calibration screws will become visible. There is a labelled calibration screw for both high and low settings. HI on the left, and Lo is on the right.
4. Turn the device over, LCD screen facing up, then carefully remove the windshield ball.
5. Turn on the sound level calibrator, set to 94dB, and place over the microphone.
6. Wait for the reading on the C-DSM1 to stabilise.
7. If the reading on the C-DSM1 is stable and not at 94dB, use a small screwdriver to adjust the HI calibration screw. Adjust the screw until the result on the screen matches the output of the calibrator at 94dB.
8. The HI level calibration is complete. The second stage of the calibration is to perform a low calibration. This time adjust the setting to low. To do so, as selected at step 2b, Press the HI/LO button this time until LO appears on the LCD screen. The other four functions remain the same.
9. Once in LO, wait for the reading to stabilise.
10. When stable and if not at 94dB, use a small screwdriver to adjust the LO calibration screw until the reading on the screen matches the output of the calibrator at 94dB.
11. Remove the calibrator and turn it off.
12. Replace the battery and the battery compartment cover then screw back into place
13. The calibration for the meter is complete!

Conclusion

For accurate and repeatable sound level measurements, its vital to calibrate the C-DSM1 sound level meter. Not sure if this is the task for you? Instrument Choice offers a range of calibration services. View the calibration services here or contact us for further information!

Additional Links

• View the C-DSM1 Sound Level Meter features and specifications here.
• Watch ‘How to Calibrate the C-DSM1 Sound Level Meter’ again.
• Watch an Instrument Choice Scientist ‘Taking measurements using the C-DSM1 Sound Level Meter’.
• Want to know what comes in the box? Watch an Instrument Choice Scientist ‘Unboxing the C-DSM1 Sound Level Meter’.
• View the range of Instrument Choice Calibration Services.
• Contact us!