The NEW BSWA 308 is a new generation digital sound level meter upgrade from base BSWA 308.  The new types update the dual-core (DSP+ARM) architecture to single chip ARM with FPU, and update all fix-point calculation to float-point which significantly improves the accuracy and stability. Re-design analog front end circuit also lower the noise floor of sound level meter.


  • Class 1 (NEW BSWA 308) and Class 2 (NEW BSWA 309) sound level meter
  • Comply with IEC 61672-1:2013, ANSI S1.4-1983 and ANSI S1.43-1997
  • Real-time 1/1 (included) and 1/3 Octave (optional) in accordance with IEC61260-1:2014 and ANSI S1.11-2004
  • Linearity range: 20dBA~134dBA (Class 1), 24dBA~136dBA (Class 2)
  • Single range to cover 123dB dynamic range
  • Frequency weighting A/B/C/Z. Time weighting Fast/Slow/Impulse
  • 3 profile calculation in parallel with different frequency/time weighting. 14 simultaneous custom define measurement
  • Calculate SPL, LEQ, Max, Min, Peak, SD, SEL, E
  • LN statistics and time-domain curve display
  • User define integral period measurement
  • High speed ARM with FPU (Float Point Unit) to achieve wide dynamic range and low noise floor
  • 4G MicroSD card (TF card) mass storage
  • RS-232 remote control port
  • Mini thermal printer for measurement data print
  • Internal GPS module (option)


  • Basic noise measurement
  • Environmental noise assessment
  • Product quality check
  • Evaluation of noise reduction engineering

Single chip high speed ARM with FPUUSB port function implemented
White backlight LCDUpdate firmware via USB (also power supply)
Integral period from 1s~24hTimer feature support auto measurement
0.1s, 0.2s, 0.5s logger step addedInternal GPS (option) with GPS timing
5 templates to save user settingSingle range to cover 123dB dynamic range
B-weighting added to meet ANSI standardReduce the noise floor (only for Class 1)
Automatic power on with external supply, ease of integration

Upper limit of measurement: 136dBrms/139dBpeak (40mV/Pa)

TypeNEW BSWA 308
AccuracyClass 1 / Type 1
StandardGB/T3785.1-2010, GB/T3785.2-2010, IEC60651:1979, IEC60804:2000, IEC61672-1:2013, ANSI S1.4-1983, ANSI S1.43-1997
OctaveReal-time 1/1 Octave: 8Hz~16kHz Optional Real-time 1/3 Octave (optional): 6.3Hz~20kHz GB/T 3241-2010, IEC 61260-1:2014 ANSI S1.11-2004. Base 10 system
Supplied MicrophoneMPA231T: 1/2” prepolarized measurement microphone, Class 1. Sensitivity: 50mV/Pa. Frequency Range: 6.3Hz~20kHz.
Mic InterfaceTNC connecter with ICCP power supply (4mA/24V)
Detector / FilterAll float-point digital signal processing (digital detector and filter)
Integral Period1s-24h user define integral period. Repeat time: infinite, 1~9999
Measurement FunctionsLXY(SPL), LXeq, LXYSD, LXSEL, LXE, LXYmax, LXYmin, LXPeak, LXN. Where X is the frequency weighting: A, B, C, Z; Y is time weighting: F, S, I; N is the statistical percentage: 1~99.
24h MeasurementAutomatic measurement and log the history data
Frequency WeightingParallel A, B, C, Z (It can also be applied to 1/1 and 1/3 Octave)
Time WeightingParallel F, S, I and Peak detection
Self-noiseSound: 18dB(A), 23dB(C), 31dB(Z) Electrical: 11dB(A), 16dB(C), 21dB(Z)
Upper Limit134dB(A) Increase to 154dB(A) with 5mV/Pa Microphone
Frequency Response6.3Hz~20kHz
Linearity Range20dB(A)~134dB(A)
Dynamic Range123dB (11dB(A)~134dB(A))
Peak C Range45dB(A)~137dB(A)
Range SettingSingle range
Sampling Rate48kHz(Sampling interval for LN: 20ms)
Noise CurveTime domain noise curve display. Duration time: 1min, 2min, 10min
LCD Display160x160 LCD with white backlight, 14 step contrast level
Mass Storage4G MicroSD card (TF card)
Post-processingPost-processing software VA-SLM can read, analyze and generate reports of store data
Export DataDirectly connect to the computer to read the memory card (USB disk)
OutputAC (max 5VRMS output), DC (10mV/dB), RS-232 serial interface and USB virtual serial port
AlarmUser define alarm threshold. LED indicate the alarm status
Power Supply4x1.5V alkaline batteries (LR6/AA/AM3), sustainable use of more than 10 hours. It also can be supply by external DC power (7V-14V 500mA) and USB power (5V 1A)
RTCBuilt-in backup battery has been calibrated at factory to the error <30s in 30days (<10ppm, 25?C). It can keep RTC running when replacing the main batteries. GPS timing function available (option with GPS module)
Firmware UpdateUpdate firmware via USB port
ConditionsTemperature: -10℃~ 50℃. Humidity: 20% ~ 90%RH
RT TemperatureReal-time temperature display on the main screen
Size (mm)W70 x H300 x D36
WeightApprox. 620g, including 4 alkaline batteries
GPS(option)Receiver Type: 50 Channels; Time-To-First-Fix: Cold Start 27s, Warm Start 27s, Hot Start 1s; Sensitivity: Tracking -161dBm, Reacquisition -160dBm, Cold Start -147dBm, Hot Start -156dBm; Horizontal position accuracy: 2.5m, Timing accuracy: 30ns, Velocity accuracy: 0.1m/s; Update Rate: 1Hz, Operation Limits: Dynamic≤4g, Altitude<50000m, Velocity<500m/s
Calibrator(option)CA111, Class 1, 94dB/114dB, 1kHz
Printer(option)Mini thermal printer, RS-232 port

BSWA 308 Class 1 Sound Level Meter

  • Brand: BSWA
  • Product Code: 308
  • Availability: Allow 2 - 3 weeks for delivery
  • $2,656.50

  • Ex Tax: $2,415.00

Available Options