I2S Audio Issue

[keperk]

This is my first build, and for some reason I decided to use the Adafruit MAX98357A combo DAC/AMP instead of the usual PAM8302 setup... I have it mostly working, but when I wire everything up through the potentiometer and headphone jack I can only get sound through the headphones. I've tried a bunch of different wiring options for the speaker but nothing has worked.

Here's my current audio setup, any advice is appreciated!

Screen Shot 2018-03-23 at 11.26.00 AM.png (294.91 KiB) Viewed 4694 times

[jakejm79]

Not sure where you came up with the wiring but it is all wrong.

Ground should run from -ve on the amp, ground connection on pot, ground on the head phone jack and ground on the speaker.
Positive runs from +ve on the amp, input on the pot. Then you run output on the pot to input on the headphone jack (you may want to connect both inputs together, the amp only outputs mono (a downmixed stereo version) this will give you audio to both L and R channels but it wont be true stereo), then output from the headphone jack to +ve on the speaker (in reality no need to worry about speaker polarity on something so small and with such low power).

If you have a 5 pin pot just ignore the input/output for one channel since its a mono amp.

[keperk]

Thanks Jake! Appreciate the detailed reply. I have a 3 pin potentiometer as well, should I use that instead?
Here's a new diagram (hopefully following your advice) let me know what you think. I'll try it out when I get home tonight.

Screen Shot 2018-03-23 at 1.54.56 PM.png (368.85 KiB) Viewed 4687 times

[jakejm79]

That looks about right, depending on the pinout of the pot, I've always used 3 pin ones with the amp since its mono anyway. You can probably also get away with just one wire from the headphone jack to speakers for the +ve side (i.e. either 4 or 3 since the amp has already downmixed the stereo to mono).

[keperk]

I switched over to a 3 pin pot, and switched the wiring around to match your advice. I'm still not getting audio out of the speaker though when the headphones are unplugged. I tried attaching the speaker to 1 pin and 2 pins. If you have any other suggestions I'd love to hear them. At this point I'm wondering if it might be an issue with the jack. It's from an old laptop I had lying around. So if I can find another one I'll try again.

[jakejm79]

I'd make sure you have the headphone jack wired correctly, it may not even be possible depending on it (some laptops use a combo mic/headphone port rather than a switching headphone port), basically you want to check for continuity between two pins with headphones out and then no continuity when you plug them in, if you find those two pins then you want input to one pin and output to speaker on the other pin.

[cbafun]

I know I'm late here, but there might be another problem with your connections. The older switching headphone sockets are only 3-poles, left, right and ground. Most new headphones, like apple, Samsung etc are 4 poles, left, right, mic and ground. Depending on the brand of headphones you are using, you might not be getting sound, as you are using a mono signal and the sound is trying to play audio though what will be ground or mic in on your headset. This might not be the issue, but worth knowing.

Here is a link to the 'old' switching socket: https://www.adafruit.com/product/1699
Here is a link to the 'new' switching socket: https://www.cui.com/product/interconnec ... 504-smt-tr