dirkenstein
Active member
Based on an idea from here:
https://www.hackster.io/janost/audio-hacking-on-the-esp8266-fa9464
I've just built a filter you can place in front of an AudioInterfaceI2S object that converts a single AudioStream stream to a PDM modulated stream with half the bits on one and half the bits on the other output channel.
When used with an i2s DAC this of course produces some fairly horrible noises, but when your DAC is replaced with a simple RC low-pass filter the output is passable audio.
Could this be useful for low-component-count Teensy 4.0 projects or for any Teensy unable to use a 12bit DAC for audio output?
It basically makes a pretend mono 16-bit DAC with a single resistor and capacitor directly connected to the i2s output.
https://www.hackster.io/janost/audio-hacking-on-the-esp8266-fa9464
I've just built a filter you can place in front of an AudioInterfaceI2S object that converts a single AudioStream stream to a PDM modulated stream with half the bits on one and half the bits on the other output channel.
When used with an i2s DAC this of course produces some fairly horrible noises, but when your DAC is replaced with a simple RC low-pass filter the output is passable audio.
Could this be useful for low-component-count Teensy 4.0 projects or for any Teensy unable to use a 12bit DAC for audio output?
It basically makes a pretend mono 16-bit DAC with a single resistor and capacitor directly connected to the i2s output.