DSL-331 Sound Level meter Data logger USB Recorder Product ID: DSL-331

The model  DSL-331  digital meter  is manufactured by Tecpel, and is a programmable sound level data logger equipped with back screw hole tripod connection. It has frequency range from 31.5 Hz up to 8 KHz, voltage supply of 9 V DC measuring level range from 30 to 130dB and operating temperature of 40 ºC. This is used in applications such as monitoring of safe working conditions, activity detection and recording, long-term measurement and recording of acoustic levels for environmental impact studies.

1.Auto Ranging Measurement 30dB to 130dB
2.Work with Window Software
3.32,000 Records Data Logger
4.Bar graph Indication with Back Light
5.USB cable available for optional purchase.





  • DSL-331 sound level meter data logger FEATURES:
    • Auto Ranging Measurement 30dB to 130dB
    • Work with Window Software
    • 32,000 Records Data Logger
    • Bar graph Indication with Back Light
    • RS-232 Real Time Display Software for Window 95/98/2000 and Win10
    • Frequency Weighting: A, C
    • 4-Digit Display with updated cycle 0.5s
    • 0.1dB resolution
    • Max/Min Hold Function
    • The standard Fast and Slow Time weightings
    • AC/DC signal output
    • Overload condition indication
    • Auxiliary output jack
    • IEC 651 Type II, ANSI S1.4 Type2.
    • Back screw hole tripod connection
    • External Power DC 9V input
    • Calibration Potentiometer easy to adjust


    • Standard Applied: IEC651 Type 2, ANSI S1.4 Type 2
    • Frequency Range 31.5Hz ~ 8KHz
    • Measuring Level Range : 30 ~ 130dB
    • Frequency Weighting A/C
    • Microphone 1/2 inch electric condenser microphone Display
    • LCD Back Light Function
    • Digital Display 4 digits ,
    • Resolution: 0.1dB,
    • Display Update: 0.5 sec
    • Analog Display 50 segment Bar graph, Resolution,
    • Resolution: 1dB,
    • Display update: 50mS
    • Time Weighting FAST (125mS); SLOW(1 Sec)
    • LEVEL Range : Lo: 30 ~ 80dB ; Med: 50~ 100dB, Hi: 80~ 130dB; Auto Range : 30~ 130 dB
    • Accuracy: ±1.5dB (under reference condition at 94dB 1KHz)
    • Measuring Level Range : 30 ~ 130dB
    • Dynamic Range 100 dB
    • Over and Under range Indication Function 'OVER' is displayed, while input is more than upper limit of range. ; ' UNDER' is displayed, while input is less than lower limit of range.
    • MAX/MIN Hold
    • Hold Reading the Maximum and Minimum Value
    • AC Output 1V rms at FS (Full Scale), output impedance : Approx. 100 Ω
    • DC Output 10mV/dB, Output impedance approx. 1K Ω
    • Auto Power Off 30 minutes if no operation
    • Power Requirement: One piece 9V battery NEDA 1604
    • Power Life About 50 Hours (Alkaline battery)
    • AC Adapter (option)
    • Voltage 9VDC (8~ 15 V DC Max) ; Supply current : > 30mADC
    • Operation Temperature: 0 to 40 ºC (32 to 104 ºF)
    • Operation Humidity: 10 to 90% RH
    • Storage Humidity: 10 to 75% RH
    • Weight: 10 oz(285g)
    • Accessories: 9V battery, Carrying case, calibration screwdriver, 3.5Ø plug, windscreen and owners manual.
    • Tripod Connection Hole Able to connect Camera Tripot Stand  

Q & A:

We own one of your Tecpel 331 sound level meter data loggers which we used to measure the noise levels in patients rooms. The recording range was set 30-130 dBa, in fast recording mode. We had measurements of 28 dB despite the range of 30-130 dB. Could you please explain how this happen? Our findings will be published in a scientific journal hence we may need to explain this to reviewers. 
Your help is much appreciated

Answer: Our sound level meter logger design can measure starting from 25 db but 30 dB is the
limit of our published specification. Therefore, it is possible to have 25 ~ 29 dB, if your environment  is quite calm in a closed room.

Q & A:
Does this work on Windows 10?
I want to connect the DSL-331 to my PC using the supplied ‘USB to RS232 adaptor cable’.
I have installed the software which runs OK but ‘No Connection’ on Com3 after connecting meter.

Hello dear customer:
Thank you for purchasing our company's products. Regarding the driver question you asked, this is because Microsoft's Windows incorrectly loaded the driver!
At this point, you need to manually specify the correct driver.
1. Check whether the driver is installed correctly, and pay attention to whether there is a driver file in this path.
2. Check that "Device Manager" displays the device name correctly.
3. If the name is incorrect, or the system displays a driver error, please manually specify the software location of 1. and update the driver.