To capture airborne sounds you need a suitable transducer (or microphone). Do you have a transducer that responds up to 150 kHz ?
The sampling rate should be 300k, or twice your desired frequency.
300 kS/s is the minimal sampling rate according to Nyquist theorem. Practically, there must be a margin between the highest signal frequency and fs/2 to allow feasible anti-alias filters. 330 to 350 kS/s is more realistic.
Regarding VS1053, just review the datasheet. It's maximum sampling rate is 48 kS/s. Maximum sampling rate of high performance audio ADCs is 192 kHz or slightly higher, not suitable for 150 kHz signal bandwidth.
You didn't yet mention intended ADC resolution respectively recorded dynamic range.
Some digital oscilloscopes and fast data loggers can easily sample at that rate.
I suppose it depends on how long you wish to record for, milliseconds or hours ?
Suggests that you have no actual clue why and how you want record sound with "0 - 150 kHz frequency" range. What's the purpose of recording ultrasound? Or is 150 kHz just a typo?I need to use a microphone for recording sounds.
But I don't know exactly what features should this microphone have?
Suggests that you have no actual clue why and how you want record sound with "0 - 150 kHz frequency" range. What's the purpose of recording ultrasound? Or is 150 kHz just a typo?
I think the point should be clarified before discussing other details. Microphones with 150 kHz frequency range are available but cost a small fortune.
There is a chapter in the 1977 National Semiconductor pressure transducer handbook that refers to microphone applications of pressure transducers.
They suggest a frequency response of dc to 30-50 Khz is possible.
Its interesting because they mention hydrophone applications and use of parabolic reflectors.
These only cost a few dollars, and already have a built in preamplifier, so might be worth a try initially.
View attachment 134127
Here is a download of that entire book.
Chapter 12 is what you want.
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Many years ago, I helped an acquaintance to build an heterodyne type wildlife listener. It was not my design, it was a kit which I assisted to build.
Listening at night is fascinating. One of course can hear crickets and other small insects chirping.....but there are other noises at ultrasonic range too.
Thinking about this a bit more...
Probably the most suitable commonly available low cost microphone might be the electret type. These work from below 20Hz to around 30 Khz and are quite sensitive.
They will not go to zero frequency as the previously mentioned pressure transducer will, but otherwise it might be your best starting out point for this project.
That, and a parabolic reflector should give you an sensitive and very directional microphone.
A microwave dish might be best, and these come in all sizes up to really huge things.
http://www.openmusiclabs.com/learning/sensors/electret-microphones/
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Do you have a rough idea of produced sound level and intended "speaker" directivity?What is your idea about the appropriate speaker and related circuits?
Is there any speaker which supports this rang of bandwidth?
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