Digital MEMS Microphone Data acquisition.

[Ethan25]

Hi,

I'm using INMP441 - 24 bit digital mems microphone.
I'm trying to collect data at 44.1KHz sampling rate

so for a minute (60sec),
44100 * 60 = 2646000 samples
for 32 bit,
2646000 * 4 = 10,584,000 ~ 10MB

assuming I do at 16KHz,
16000 * 60 = 960000 samples
for 32 bit,
960000 * 4 = 3,840,00 ~ 3.8MB


ESP32 WROOM 32 has 512KB of RAM assuming 300KB is available for utilisation,
307,200/4 = 76,800
so,
@44.1KHz = 76,800/44,100 = 1.74 seconds
@16KHz = 76,800/16000 = 4.8 seconds

so how do i even record audio using this? am i going wrong anywhere with my calculation ? I'm confused. Thanks.

 

[KlausST]

Hi,

the third thread with similar topic.

so how do i even record audio using this? am i going wrong anywhere with my calculation ?

In the other thread you ask why they use 16 bits instead of 24 bits. I guess you already know the answer now.
AND .. in the other thread I and others already talked about compression...
And... I already meantioned real time processing and storing algorithm... to save data space.

A simple conclusion also is, that RAM it not a suitable medium for huge audio data storage.
SD-cards, SSD or HDD may be more suitable.

Klaus