Volume pot turned all the way down but sound still a little loud

[Lphillimore]

Guys, checkout PWM2 - it's in the early stages but seems to be a massive improvement and negates the need for heavy filtering etc.

Wait im sorry im not informed enough to know what that is, is it like another type of amp? Can I get a link to read what it is.

Helder flagged it here: https://www.raspberrypi.org/forums/view ... &start=200

Its PWM - mode 2.

Essentially still in testing so to speak but potentially a lot cleaner....just update your Pi and change your config.txt and give it a go....

[firestw152]

Guys, checkout PWM2 - it's in the early stages but seems to be a massive improvement and negates the need for heavy filtering etc.

Wait im sorry im not informed enough to know what that is, is it like another type of amp? Can I get a link to read what it is.

Helder flagged it here: https://www.raspberrypi.org/forums/view ... &start=200

Its PWM - mode 2.

Essentially still in testing so to speak but potentially a lot cleaner....just update your Pi and change your config.txt and give it a go....

Wow this is interesting thanks for letting me know! So I just download the latest version of retropie and I can activate pwm2? Or is there something else I gotta do.

[Lphillimore]

As far as I'm aware, yes. Post update, Just amend your config file to include:

audio_pwm_mode=2

Let me know how you get on

[firestw152]

While waiting for the USB sound card i thought i could setup another pi to test/improve the mono PWM audio i used on my first build. This time im using no low/high pass filter. Just the audio amp(PAM8302A) directly connected to the pi zero's GPIO 18. To my surprise it sounded great and can't seem to hear any difference from my first build with filter.

I made another change by placing the volume pot between the pi's gpio18 and the audio amp which i think is a good practice. The only problem is, the sound is still a little loud even if the volume pot is turned all the way down. Maybe im doing it the wrong way. Im not sure.

IMG_1448.JPG

Any help or input is welcome and will be very much appreciated! Thank you!

Update:
It looks like the PAM8302A doesn't need any filter after all.

Oh hey zeroboy I completely forgot to respond to your question. I had the same problem where the amp was making the speaker to loud for the pot to turn it off so I solved this issue with a 22 ohm resistor. If you have 20 or 10 ohm resistors I recommend starting from 10 and see if you need a 20 resistor that way your speaker does not loose that much volume.

[tinkerBOY]

Mine works great already. Check http://www.sudomod.com/forum/viewtopic. ... 484#p39467

[firestw152]

Hmm Guess I need the low bypass filter now for some reason I dont know what im doing wrong. I have gpio 18 wired to the headphone jack and I get some weird hiss and like pops whenever I turn the volume pot wheel. Any suggestions?

[tinkerBOY]

Hmm Guess I need the low bypass filter now for some reason I dont know what im doing wrong. I have gpio 18 wired to the headphone jack and I get some weird hiss and like pops whenever I turn the volume pot wheel. Any suggestions?

Can you post a picture on how you wired it?

[firestw152]

Hmm Guess I need the low bypass filter now for some reason I dont know what im doing wrong. I have gpio 18 wired to the headphone jack and I get some weird hiss and like pops whenever I turn the volume pot wheel. Any suggestions?

Can you post a picture on how you wired it?

Well I fixed the hissing and popping noises from my headphones and now they sound crystal clear and the pot wheel works with them but now the speakers don't work. They are very low and you can only hear it if you put your ear right up against the speaker and when you do you just hear more hissing or static than gameplay.

https://photos.google.com/share/AF1QipN ... swbG5sd0lR

Here is how I wired it, it makes the headphones work beautifully like I mentioned but the speakers are not working.

Edit actually the pot wheel diagram is wrong I have the radioshack pot and its wired facing up pin 2 as audio in and pin 5 as audio out.

[tinkerBOY]

Adjust the pot on the audio amp.

[firestw152]

Adjust the pot on the audio amp.

I did, its as high as it can go I dont know whats wrong.