Solved Audio Noise

cheese

the tallest memer in town
Staff member
.
.
.
Joined
Mar 2, 2016
Messages
2,759
Likes
2,431
Location
Florida
I can't hear the gamecube but I can still hear the buzzing but only slightly. Is this the dc offset you were talking about?
No, something like this is DC offset, where the dotted lines are the limits of the amp's input.
IMG_20160522_170437.jpg

This may be interference somewhere in your amp or speakers...
 

Aurelio

ᕕ( ᐛ )ᕗ
Staff member
.
.
.
.
.
Joined
Mar 3, 2016
Messages
2,228
Likes
2,952
Portables
2
tried that and on a new gamecube....same thing.

This is another strange part. So it's louder when I turn the volume up (duh on my part) but when I put the volume to min I can't hear the gamecube but I can still hear the buzzing but only slightly. Is this the dc offset you were talking about?
If it was just an offset you wouldn't hear it.
Can tou try with difference speakers?
 

ShockSlayer

the real
.
.
Joined
Jan 16, 2016
Messages
1,512
Likes
3,940
Location
standing up
Portables
please do not ask!!!! I will NOT respond
Shielded wire(GND connected at both ends) for everything usually fixes all of my problems. Are the AVE-DOL legs the only place you can grab audio from the board?
 
Joined
Mar 17, 2016
Messages
39
Likes
5
@cheese it might be both I have checked two different cheap pam8403 amps and they both have the same issue.

@Aurelio tried it with two speakers and headphones

@Noah no fans at this point to see if they were producing noise.

@ShockSlayer Are you saying every single wire is grounded? The legs, two solder pads and the preamp are where I have been attaching onto.

So I'm going to try more things: Separate the amp circuit completely and try it out. If I can make a separate 3.3 rail and see if that cleans it up. And at that point I will try to get more amps and make some from oshpark to see if I can do this.

Also what high pass or low pass filter would I need to make?

btw thank you all for helping me with this. Much appreciated.
 

cheese

the tallest memer in town
Staff member
.
.
.
Joined
Mar 2, 2016
Messages
2,759
Likes
2,431
Location
Florida
Also what high pass or low pass filter would I need to make?
If you intend to remove the buzzing with a pass filter, it would probably be best to try a new amp to save on space and time. Also, you probably won't be able to remove the buzzing sound without also removing some of the audio.
 

ShockSlayer

the real
.
.
Joined
Jan 16, 2016
Messages
1,512
Likes
3,940
Location
standing up
Portables
please do not ask!!!! I will NOT respond
Yep, wires on all of them.
 
Joined
Mar 17, 2016
Messages
39
Likes
5
Yep, wires on all of them.
I wasn't able to get good shielded wire at any of the box stores but I took apart an 1/8th stereo cable which served kind of the same purpose and it made things really manageable. Thank you ShockSlayer B|. Seems you had this same dilemma with Tchay many many moons back. So I'm guessing my power lines are just oozing rf at this point. I'll try to get some good shielded wire and update whenever I can.


edit: Is it wrong to connect both ends of the shield? Wouldn't that just make another ground loop?
 
Last edited:
Joined
Mar 17, 2016
Messages
39
Likes
5
So with new shielded wire and a new amp that was hidden in some usb powered aux in speakers it works with no interference. YAY. Thanks everyone for the help. Sorry this scratched brains.
IMG_20160524_201955.jpg
 
Top