Clap Counter User Guide
Count claps or other sound events with this app. The sound level is continually monitored and when the clap count threshold is passed, the counter is increased by one.
To prevent double counting, no further count increments are done until the sound level drops back below the count threshold plus the extra trigger reset distance given in the detection settings. Further counts can also not occur until the trigger reset wait has passed, typically a few extra readings, again to prevent double counting of sound events. The graph shows a blue line whilst it is unable to trigger a new sound event. Tweak the detection settings to best detect the sound event you are measuring.
The zero button resets the counter and clears the graph.
The pause button pauses measurement until it is pressed again.
App is For Indication Only. Sound level depends on how close the source is to the microphone. Microphone sensitivity varies with frequency and from device to device. The range between the noise floor and saturation may be only 20 dB on cheap devices, but could exceed 100 dB on the best devices.
The speed arrows allow the measurement frequency to be changed between 10 preset values (0.5 Hz, 1 Hz, 2 Hz, 5 Hz, 10 Hz, 20 Hz, 50 Hz, 100 Hz, 225 Hz and 450 Hz). These frequencies are chosen to give a wide range of measurement speeds whilst keeping an exact number of samples per measurement (based on 44.1 kHz audio input). Faster speeds will use less data per measurement and therefore be noisier. For slower speeds the 'clap' event may only make up a small part of a measurement, such that the sound level is lower.
Clap count threshold - To detect a sound event, the measured sound level must go above the clap count threshold given in this section and shown on the graph with a yellow line. Use the arrows to adjust the threshold or enter a value by going into the settings menu.
Trigger reset distance – the signal must go below the thinner orange line before the app will start listening tor another sound event. If the trigger reset distance is zero, then the orange line will be at the same value as the clap count threshold yellow line, and this will suffice in most cases. For more robust counting, it may be preferred to increase the trigger reset distance depending on the signal being investigated.
Trigger reset wait – To avoid signals being detected to close together, a wait can be added so that another count will not be made until after the wait period has passed.
Count Detection Settings
The graph shows the change in sound level versus time. It is auto scaling and scrolls once filled. If the clap count threshold is within the auto scaled range, it is shown by a yellow line. Where the sound level goes above this line and a count is registered, a red circle appears. A subsequent blue line follows where another clap event cannot be registered as determined by the detection settings. After which the trace returns to white indicating that another clap count will be registered once the sound level once again goes above the threshold.
Clicking the cogs button at the top left of the screen brings up a settings menu:
Reset to defaults – this resets all preferences back to their default values and zeros the counter.
Edit counter value – Use this if you need to adjust the counter value.
Edit detection values – you can also edit the detection values here, typing in the values rather than using the arrow buttons.
Copy counter value to clipboard - this will copy the current counter value to the clipboard, ready for pasting into another application. Long tapping on the counter value also copies its value to the clipboard.
Edit dB offset – Add an offset to the dB values. The sound level shown is based on the rms of the signal and will approximate the SPL value in dB. Since microphone sensitivity will vary between devices, you might want to adjust the measured sound level up or down by adding an offset.
Show counts/min - this option allows the counts per/min reading to be shown or hidden.
Stay awake – check this option to stop the device from sleeping.