Hello, I want to build an audio recorder. I saw a lot of different microphones and chips to make it happen. But I’m confused on what to really use. I’m asking the community what is the hardware I would really use to make a voice recorder?
Joseph
There are two kinds of microphone boards:
There are analog board has a preamp that puts-out a biased analog signal. I have this one. A microphone itself only puts-out a few millivolts so you always need a preamp. And since audio goes positive and negative but the Arduino's analog-to-digital converter can't read negative voltages so it has to be biased. The bias can be subtracted-out in software.
There are also boards that add an analog-to-digital converter. These usually have better performance than the ADC on a "basic" Arduino.
There are other audio boards that detect "loudness" without putting-out an audio waveform and those won't work.
Note that some Arduino's don't have a DAC, so no true analog output for playing-back audio. (But low-quality analog can be "faked" with the TMRpcm.h library.)
The Audacity Website has a good basic introduction to how digital audio works.
P.S.
You'll also need to make sure you've got enough memory. For example, "CD quality" audio is 16-bits at 44,100 samples per second. There are 8-bits in a byte so every second of mono audio requires 88,200 bytes (double that for stereo).
And FYI - Good-quality audio is "difficult" because our ears are very sensitive to noise. And with a preamp, any electrical noise gets amplified.
For a jump start on the topic you can go to sparkfun or adafruit websites and see what they have for breakout boards and hookup guides. A quick search for sound recording finds many, this one looks interesting https://www.adafruit.com/product/1381
There’s very detailed tutorials, schematics, and photos, basically a step-by-step guide you can get started with.
The Adafruit Clue has everything required to record up to 60 seconds of good quality audio to a file on the built 2 MB memory chip, and would be a fine place to start.
Hi sorry sorry I have not been here. I got the flu and now got my whole family blaming me. Which makes me happy. lol!!
I’m reading all comment and I thank everything for the reply’s back. I will reply back to everyone. I just wanted to tell what I found so far. There are many microphones from analog to digital from i2c to SPI. I honest Lu didn’t know which one to choose from. I found some on adafruit to Amazon. That is why I came in here to ask.
So do you now know which one to use?