Author Topic: lm386 speaker problem statics noises HELP (Read 3156 times)

tapdisbong · « **on:** July 31, 2009, 03:26:08 AM »

i'm doing the lm386 mod now, i did everything correctly but when i boot up the psp all i hear is static from it and heavy bass. i used a 10v 100uf capacitor. everything is wired correctly and neat, there is no shorts. I also tried 3 different speakers all same results, 2 from headphones one from the house phone (lol) somebody help. The house phone speaker is 8ohm 0.3 watts. the other 2 i don't know what they are.

I added 2 speakers and the static decreased a little when there is no music or anything playing. Can this happen because i have it connected to the hold switch + other leds connecting to the hold switch?

atomicareprise · « **Reply #1 on:** July 31, 2009, 04:22:33 AM »

same prob happen to me as well...connected all the wiring and stuff but all humming..

tapdisbong · « **Reply #2 on:** July 31, 2009, 05:42:15 AM »

did you fix the problem yet ? maybe there too much current going through maybe we have to use resistors ?

EDIT: i got the constant buzzing to go away. I had to pink leds hooked up to the hold switch i took it of and the constant buzzing just stopped. i tried a 1/2 watt resistor and a 56k om resistor but the sound stopped working wen i used it. Rite now theres no constant buzzing but, when you boot up the psp or listen to music/games it sounds all cracked up.
i think the problem might be wit the speakers now.

atomicareprise · « **Reply #3 on:** August 01, 2009, 06:59:41 PM »

nope it did not work for me..i gave it up...

i use 1/4 wattage for my resistors...

i also use 100 uf capacitor like rceck told me ...

but can't get it work...

tapdisbong · « **Reply #4 on:** August 01, 2009, 11:33:02 PM »

ya i gave up on it to i tried like 10 different random resistors lol. i just direct connected the speaker to the original speakers. it suck though i was hoping to get it to work.

atomicareprise · « **Reply #5 on:** August 01, 2009, 11:55:08 PM »

how come others do work for them..

tapdisbong · « **Reply #6 on:** August 02, 2009, 09:32:43 AM »

i don't know. its mind boggling lol

atomicareprise · « **Reply #7 on:** August 02, 2009, 10:09:01 AM »

rceckspurt13 · « **Reply #8 on:** August 02, 2009, 08:22:02 PM »

Possibly you had the cap in backwards? Solder the - side directly to the speaker.
Also when I did mine with the cap, I didn't use any resistors on the audio input lines.
Also, the hold switch is a ground. You mentioned it above as a +.

tapdisbong · « **Reply #9 on:** August 02, 2009, 08:39:15 PM »

ya i did all of that correctly. heres the diagram i used, i just soldered the ground to the hold switch.

rceckspurt13 · « **Reply #10 on:** August 03, 2009, 01:45:00 AM »

Thats my diagram

But now that i think about it, when i did mine, i used an un-amplified audio source(standard headphone connection). it may be the voltage interfering from the psp speaker.

you may want to play with the resistors on the audio lines. also, maybe add another 100uf cap to the +audio in from the psp speaker. i dont know if that will stop the noise, but its worth a shot. just hook it the same way with the -side to the amp.

atomicareprise · « **Reply #11 on:** August 03, 2009, 02:00:30 AM »

yeah rceck did that diagram when i ask him how its done...

tapdisbong · « **Reply #12 on:** August 03, 2009, 11:40:08 AM »

ya i added two static lessened then 3 same thing. i'll try more resistors tonight. what kind of resistors did you use ?

atomicareprise · « **Reply #13 on:** August 03, 2009, 09:39:25 PM »

in my case i use 190k and 30k with 1/4 wattage..

i use 100 uf capacitor with 10 volts..

ryan0 · « **Reply #14 on:** August 17, 2009, 04:13:27 AM »

sounds like you're drawing too much current from the speakers,either that or you've just blown your sund chip (it happens,I've done it before).

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