i2s_adc_dac no audio output

[shirogeek]

Hey guys,

I basically copied , compiled and ran the example in i2s_adc_dac however, I hear no audio at the end. I see printed DAC values in the console as is expected but i only hear white noise in my earphones. From the example instructions, I understood I could directly connect my earphones' L,R,GND to PIN 25,26,GND to the opposite of my instinct where i would need an amp to amplify the DAC. Is my understanding correct ? I do not need high quality audio at all so if I can get away with this it's good but the dac cannot directly drive earphones,correct ? Or is something wrong with my hardware ?

Thanks in advance

[becorey]

It looks like that example first uses a microphone to record sound, then plays back the sound. You didn't mention it in your post, are you using a microphone? If not, you might be hearing static because there was no audio input from the mic.

[shirogeek]

thanks for the reply !
in the example there are three parts from what i understand : 1st audio is recorded through mic 2nd audio recorded is played back and 3rd a small music is played ( encoded in an array). I'm only interested in the third part as with flags at the beginning of the code you can disable the first two.
But this still brings back to my original question is it even possible to drive earphones with DAC directly ? I have never seen this personally before always knew an amp was needed

[ESP_Sprite]

Earphones are an inductive load, and I'm pretty sure that from an official point of view I can't advise running an unknown inductive load from the internal DACs. Unofficially (as in: as long as you don't make a commercial product out of it and complain to us if it breaks) it should be fine, at least for a short while. No guarantees about audio quality, though, I have no idea what the frequency response of the DAC outputs under load is.