A place users can post their projects. If you have a small project and would like your own dedicated place to post and have others chat about it then this is your spot.

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By roscop13
#41443 First thanks for the great work!
I added a DAC and the sound is great. Still, without the SPI memory I do have some lag that is getting worst an worst after 5minutes.

I have a naive question : on an ESP8266 with 4Mo of flash, could this flash be used to allow more RAM to buffer the MP3 stream and avoid the use of a separate SPI RAM chip? or is there another benefit of using a 2nd SPI chip?

Thanks for you help
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By isti37
#42571 I would like to drive a H-Bridge gate driver of a class D amplifier with a PWM/PDM signal/channel with ESP8266. Due to the 160 Mhz the ESP8266 can be a decent modulator for a D Class amp.

But, I don't see how this chip can handle a 320 kbps data rate, the best receive speeds I found on the internet are 20 kb/s IN THE BEST CASE with UDP and that's still only 160 kbps. Most of the times however the receive speed will be about 10 kb/s or even lower. If we optimize the TCP stack we could get a constant 15-20 kb/s for 160 kbps streaming and that's more than enough for most people, but still suboptimal compared to only a little more expensive chips.

Also I don't think that MP3 streaming or decoding with MAD is any good, the Opus codec would be a MUCH MUCH better option than MAD because opus supports variable bitrates and multiple channels while MAD supports only 1 channel. An MP3 to Opus service is a simple nodejs/python server with ffmpeg and libopus.

If one could implement an opus codec decoder for ESP8266 this little thing would become way more awesome even with 128-160 kbps. Those who need higher bitrates are pretty much f.-ed by the low Rx speed unless buffering is acceptable so there is no reason to buy an expensive DAC module to use with this chip.
https://www.opus-codec.org
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By pali52
#43821 Congratulation, Sprite_tm for this super works!
Hard work for some days and now I can hear the music! :D The next step is to connect a PCM5102 board (I made it to RPi) to the I2S output. Only one thing what I don't understand. When I uploaded the eagle.flash.bin and theeagle.irom0text.bin files to ESP8266, it didn't work, I had to upload blank.bin files, as rudi wrote last year in nr.19829. Would somebody explain why is this?