Go Direct® Sound Sensor (GDX-SND)
Specifications and User Guide

– Primary Test
Microphone Channel – The easiest sound source to use with the Microphone is a tuning fork, but you may want to investigate a human voice or a whistle, electronic keyboards, and other musical instruments. Make sure the sound level is in the correct range to produce good wave patterns. If the sound is too loud, the wave pattern will be clipped at the top or bottom. Move the microphone further from the sound source, or turn down the volume of the sound.

An inexpensive keyboard set to the flute sound, without vibrato, is the best source; you can easily do both beats and pure tones of varying pitch.

Sound Level Channels – Normal classroom sound levels should be 60-70 dB; a quiet office should read around 55 dB.

– Minimum software version: Graphical Analysis version 4.5, LabQuest App version 2.8.4

What are the units (of pressure) for the microphone?
What is the best procedure to get a clean sine wave when using a tuning fork with the microphone?
What is the best sound to use for the speed of sound experiment?
How do I use LabQuest App to measure the frequency of sounds?
Can I submerge the Vernier Microphone in order to measure the speed of sound in water?
What is the difference between the Sound Level Sensor and the Sound Level Meter?
What advantages does a Vernier sound level sensor have over a smartphone sound level app?
What is the difference between "A weighting" and "C weighting"?
Why doesn't my sound level meter read below 40 dB?
How can I create FFTs using the Go Direct Sound Sensor (GDX-SND)?

Response: A- or C-weighted
Range: 55-110 dB
Accuracy: +/-3 dB
Resolution: 0.1 dB
Sound Level Frequency Range: 30-10,000 Hz
Microphone Level Frequency Range: 100 Hz to 15 kHz
Typical Max Frequency: 10,000 Hz

The Microphone and Wave Amplitude channels are uncalibrated, which means that the vertical axis has arbitrary units on waveform graphs. The voltage from the Microphone output is what is graphed. For more information, see What are the units (of pressure) for the microphone?.

The Sound Level channels will never need to be calibrated. Each sensor is carefully calibrated before it ships, and this unique calibration is stored on the sensor.

If the sensor can be turned on when connected by USB but not when disconnected from USB, it is likely that the battery just needs to be charged. In this case, charge the sensor for several hours and try again. If, however, the sensor won’t turn on regardless of whether the USB cable is connected or not, and you are confident that the USB cable is good by having tested it on another sensor, then the battery has likely reached its end of life and can no longer hold a charge. In this state, the sensor cannot be used even if connected by USB, so the battery will need to be replaced. The rechargeable battery in this sensor is covered by a one year warranty but should last two to five years in typical use. Note that if the battery is less than one year old and the sensor cannot be turned on even when connected by a working USB cable, another possibility is that the USB port is bad. In this case, contact Vernier technical support for assistance. 

Microphone (MCA-BTA)
Sound Level Sensor (SLS-BTA)
Sound Level Meter (SLM-BTA, discontinued)