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HELP just need audio
Posted: Fri Mar 10, 2017 12:39 am
by Vvizzini
Please take quick look maybe im not doing it right or maybe missing that crucial programming step im not sure.
Things ive tried.
Atleast 3 different b103 wheels 1 from a gb, thru research i read that the pins for this may be flipped.. tried it nope.
3 or 4 different speakers
2 different pam8402 amp, pam8403amp
Power Strip is working.
Ive done the proper line edit to enable the sound.
Built a low pass filter using helders board.. no sound with or without.
Initially i had planned on a headphone jack but im not even worried about that, i can figure that in after i hear some sound.
Even with this i cant get audio. (Desolder for a better pic.) Not pictured is the audio filter. I should atleast hear something wired this way for test purposes,correct??
Speaker to amp

Red n black to power
Yellow n white to wheel. White is ground
Wired to wheel. ARE THE PINS RIGHT??? Tried them in reverse as well

From here id run it thru the filter and then to pi using audio at pin18 and ground at 39.
Am i missing something on the software side??
Re: HELP just need audio
Posted: Fri Mar 10, 2017 2:30 am
by Lphillimore
@Vvizzini
Are you 100% on your config line?
Try the mono config on a separate line:
dtoverlay=pwm,pin=18,func=2
You could also try for test purposes removing the potentiometer wheel and wiring direct from Pi PWM to amp / speaker.
Re: HELP just need audio
Posted: Fri Mar 10, 2017 8:38 am
by winnston84
Is your speaker wiring correct, off the top of my head my speaker is -ve on the left and +ve on the right. Seems to me you have them wired back to front to the amp?
You should get sound using just that configuration you have yes, or some kind of noise. I think i blew/broke my adafruit 2.5w mono as i would just get hiss/static.
As suggested, you should wire just the speaker, 2.5W amp and pi and work back from there. Your b103 looks correct (Ground, Pi, blank, blank, amp).
I had issues with filter+the 2.5w amp, decided in the end to switch to USB DAC - so much better quality and easy to set up, i bought these for info:
http://www.ebay.co.uk/itm/2x-PAM8403-Mo ... 578557543?
http://www.ebay.co.uk/itm/171898196952? ... EBIDX%3AIT
Re: HELP just need audio
Posted: Fri Mar 10, 2017 1:04 pm
by Thump52
I was not going to post this reply because it might be a dump answer but I'm going to be kicking myself all day if I didn't , so here it is ,,,Have you tried turning up the volume gain (if that's what its called?) with a small screwdriver just above the A +, A- on the amp?
Hope this helps, I also had trouble with the audio and decided to go with usb sound instead, its actually a better sound and easier, just follow Wermy's guide (Thanks Wermy)
Re: HELP just need audio
Posted: Fri Mar 10, 2017 1:34 pm
by Vvizzini
100% on the line input.
Ill try another amp (good thing i bought 4)
Ive checked to make sure the pot on the amp and the wheel are set midway(so i might be able to hear something.
Ill try the speaker
I dunno maybe im just daft.
Re: HELP just need audio
Posted: Fri Mar 10, 2017 1:52 pm
by Vvizzini
I have an 8403 amp i had planned on tryin stereo with said usb setup. But that changed as i found 2 ways on how NOT to remove the jacks.. so i scrapped the usb sound n moved on.
Its a pretty basic audio setup. This is UHHHGGG just Uhhhhggg.
Anyway i do hear a slight bit of static if i put my ear to the speaker
Re: HELP just need audio
Posted: Fri Mar 10, 2017 2:49 pm
by Vvizzini
Not sure how it happened.. i reworked everything. New amp different speaker. All my connection were/are good. Was still getting same results. So i go back to the config which i KNOW i edited 3 times 1x for stereo, 1re edit for mono. And atleast 3x times verifying it was correct. So i pull the card. Edit it on the pc and the lines not there?? Input line and reinsert.
It works now..
Ill screw it up once i add vol wheel and filter.
Ill be back complaining on how i broke something while closing the case. Like this ground wire to the l/r button after i hot glued it.. fml
Re: HELP just need audio
Posted: Fri Mar 10, 2017 2:50 pm
by Vvizzini
Re: HELP just need audio
Posted: Sat Mar 11, 2017 12:05 pm
by Vvizzini
Ok like i said..
So vol wheel added n filter..
Back to almost same issuse. I have sound not even near the quality i had during the rebuild test
YES YES the cofig line is there.

Re: HELP just need audio
Posted: Sat Mar 11, 2017 1:39 pm
by Vvizzini
The wheel is my culprit..
Ill admit its very sloppy, as soon as i give it a pinch the sound gets crisp n clear