Community news, upcoming events and general discussions
Threads: 36 Posts: 88
Get technical support from the community
Threads: 1409 Posts: 7545
Threads: 18 Posts: 64
Tell us how to make XDK better!
Threads: 36 Posts: 119
Share and discuss community member projects
Threads: 78 Posts: 343
I want to Know calcuation method to XDK
Above, two function is the Initialize method.
And reeding the Acoustic data is raw. How can I changed the data calculation method? DB uinit?
The reading of the acoustic sensor is in mV. There is no API for accessing the sensor directly since we cannot provide a reliable conversion to dB at the moment. A user can calibrate and implement the conversion at their own responsibility.
Is there a conversion ratio chart to get the value for ADC? Could you explain more about how to obtain the sound pressure? I don't quite understand the relationship between conversion ratio of the DC and the sensitivity.
What's the reason behind using 50 sample for RMS based on your other post? Will using the RMS value of the raw data in milliV will obtain RMS value of the Sound Pressure?
Thank you for your explanation again, it have helped me understand better. I have also successfully calculated the SPL.
In my For loop of 50, I have received many 0 values which will end up in undefined answer as log0 is undefined.
Is this normal or how should I go about it?
Thanks for the explanation and recomendation.
I still do have some period that I'm receving 0 value, and it doesn't looks nice when I plot it out.
How fast is the acoustic sensor sampling at for 50 readings in a loop which it's called every second? Could it be possible if I'm sampling the acoustic sensor too fast that it will return a 0 value instead?
What's the possible solution for me to have a more stable results??
Good to know that the data is valid.
Thanks for the info.
According to my calculation the range could go up to about 130 dB SPL if I'm not wrong. Unfortunately, I 'm seeing some saturated data that looks like its clipped off at about 120dB SPL.
I have tried calibrating my data with -30db referencing to my phone acoustic sensor to get a more appropriate reading around 40-50db in the room. Hence, the final calibrated value is saturated around 90db SPL. So, why is there a saturation occured at around 90db SPL?
Thanks for the explanation. I'm wrong on the maximum value.
Where can I find the datasheet stating that it has a gain factor of 10? I am unaware of it. For knowledge purposes, how did you calculate that 20db = gain factor of 10?
In addition, how would you recommend me to decide on which sensitivity value should I use?
After reducing the SPL by 20, can I say the limit of the sensor reaches a maximum of 100dB SPL only?
I have understood what you have mentioned. Thank you !!
However, I dont quite understand why did you choose 20Pa and how did it results to 0.2518V?
Another question is, how do I determine which sensitivity value(-36,-38,-40) should I use for my calculation?