Hardware GBA speaker noise fixed!

[RemixDeluxe]

Original speaker is the best one you can get, believe me.

No way I don't believe that. You can even get better quality just from plugging directly into the headphone jack. It's not the same as the speakers. Compare it with any GBA game music.

 

[Peeteris]

[...]

about the volume, actually you can mod louder. since some time passed so i barely remember, but C39(or 38?) resistor affects the volume. higher ohm does louder volume and lower ohm does quieter. or the other way...? it has some flaw though.

Can someone give more information about this? I am really interested in making my GBA way louder or at least just louder.

--------------------- MERGED ---------------------------

No way I don't believe that. You can even get better quality just from plugging directly into the headphone jack. It's not the same as the speakers. Compare it with any GBA game music.

Believe me. I changed original speaker to decent quality new one and sound now is too crisp that it sounds irritating and tiny. Original one gives out a bit muffled sound but in this case it's a positive aspect.

 

[Z80]

Going to add a 16V220uF nichikon fineGOLD I had lying around from a dead high end mobo, maybe too overkill for a gba? Btw does someone know how much loud is the original GBA sound when maxed out? I think mine is quieter (at least is quieter than mi AGS001 ) I dont know what could be the cause or what to check, could it be the volume resistor? it barely offers any resistance to movement when lowering and maxing the volume I cant remember if it used to offer more resistance to movement when the gba was new.

I changed the original speaker because of that for a new one similar to those offered with the gbAMP, i didnt notice the sound to be any crispier but I still think it has a low volume when playing with the mono speaker alone.

 

[Z80]

Well did it, it was a nightmare to get that cap inside of the GBA casing, only very very few noise remains almost unperceptible when using headphones but bass is pumped up lol? Shoots on Metroid Fusion are crisper and the music is more brilliant, like when playing in GBA player /w swiss, i think I burned a lil bit one of the wires of the speaker when approaching the soldering iron and now the speaker doesnt play sound, ill check that tomorrow (I shouldnt work at 5 am xDD, but I wanted to finish it).

Maybe I could triy to add another 100uf capacitor in parallel.

 

[lostdotfish]

Just added a random 100uf 25v cap I had lying around to my GBA and it's nicely soaking up that noise. Thank you for sharing your fix.

I was thinking about the possibility of doing a stereo speaker mod to one of my GBAs. @malheur - any thoughts on if this would be possible? I guess the stereo channels aren't broken out on the motherboard (except on the headphone jack) but couldn't we tap straight from the DAC?

The 2 challenges:

Find somewhere to tap the left and right channels.
Find a way to retain the headphone muting of the speakers when connected.

Not sure if we can achieve the second challenge without engineering an add in amp (like the GBAmp3).

Couldn't we tap L&R from the volume pot?

 

[malheur]

The 2 challenges:

Find somewhere to tap the left and right channels.

Find a way to retain the headphone muting of the speakers when connected.

when you modding the component, easist way to start is read a datasheet. thats the problem. cant find anywhere datasheet of AMP AGB. so if you want to do something with it you have to try and error.

so far what i know is, stereo signal only out from the headphone outlet without amped, and the muting is also processed by amp chip, not the extra switch thingy. included volume also works with single channel.

i think its impossible with using only included components. but nowadays theres many solutions for tiny amp and the Arduino can do almost every job. since GBA has reletively large enough room and support enough power for put things, ATtiny may help mod what you want.

---

ps : i found tiny 3W amp chip named PAM8403. its stereo tiny amp chip working on 2.5-5.5V. theres regulated 3.3V power on GBA board, 3W out is good enough(actually over spec), small enough to put in the GBA, and its cheap. if you make headphone bypass switch, i guess it is possible to put stereo speaker in GBA.

 

[alcx]

Thanks for this fix, worked for me.

Before the fix, I found that powering the GBA from old batteries made the noise louder and good batteries made it less noticeable, so it could be that the DC-DC is working a bit harder resulting in more noise.

Pin 9 of the AMP is the Voltage reference pin, you can check the other pins from the GBA service manual.
Before the fix, I tried testing caps on the LPF side of the AMP, but I don't think it's really a low pass filter for the audio, it seems like it might be to adjust the volume coming from the MCU, it made some difference but the volume was reduced so your fix works better.

 

[OldSchoolTech]

You know what, every gameboy I've ever owned has done this. I decided to check the original GBA advance that I backlit modded and very surprisingly it doesn't buzz at all. Not through the speakers or headphones at all. I always just lived with it but that's kind of odd how I seen this thread then checked mine and it just happens to be silent. Maybe the used different components in some models. Mines a 40 pin GBA if that makes a difference.

 

[rigoriga]

I modded my own GBA recently, and I used a gold Nichicon 16V 100uf I had from a SNES project and I managed to get rid of the buzzing. But I now hear a high pitch whine from the system. Should I move up to a 220uf cap? I also read a guide on those chiptuner guys on using foil, but I soldered a wire from the bottom of the speaker to ground, and the problem persists. I am using a 40 pin GBA screen, but it was not a type B with a wire so I instead soldered a point near pin 103 of the GBA CPU to ground (which only fixed the ghosting issue). Or will actually getting a type B adapter fix most of my problems?

Edit. Well I did the remove parts mod as recommended. Bridging the two points was a pain mostly because I used a 1 inch piece of wire instead of a three like in that picture. The whine from the voltage regulator is more quiet, so quiet that I can hear the buzz from the speaker (which goes away after a few seconds).

 

[isoboy]

I just did this mod. I felt very confident as I've modded a lot of stuff before. First thing I do is bridge the first two pins. I don't have proper solder removal stuff and I struggled somewhat using both a razorblade and the solder iron to separate the pins. In the end it worked.

 

[Dnilo]

Thank you SO MUCH, just did the mod using a 220uf 25v capacitor (after testing a 100uf25v) and I'm super happy without that 'humm', I didn't notice much difference from the 100 to the 220, and placebo effect might have gotten into my ears feeling the 220 with a tiny bit more bass as Z80 here mentioned.

Enjoying another play through Aria of Sorrow.

Can someone give more information about this? I am really interested in making my GBA way louder or at least just louder.

--------------------- MERGED ---------------------------



Believe me. I changed original speaker to decent quality new one and sound now is too crisp that it sounds irritating and tiny. Original one gives out a bit muffled sound but in this case it's a positive aspect.

I can confirm the original speaker having better sound than others, I have built several AGB-101 mods in the past and while doing so I added an "improved" speaker to one of them, then I tested the same game running at the same time with both mine (original speaker) and the "improved one", one in each ear.

Again, thank you. Now my AGB-101 is perfect.

 

[Flexis]

*

 

[Galaga_]

Hey guys, so I made this mod both with a 100uf 16v cap and a 220uf 16v cap and I still have the buzzing and noise both on the speaker and trough my headphones.
Any ideas on what the problem could be?

 

[phreak97]

Great work fixing the hum!

Is there an equivalent mod for a gba with the Mitsumi PM B3 amp?

Like the AGB AMP google has no information to share on pinouts.

Thanks!

 

[Hammyface]

I am trying to do this fix but I only have 220uF 6v, not 16. Is a 6v capacitor OK? Or is it too "low" of a voltage?

 

[emuman100]

Has anyone tried replacing the electrolytics on the motherboard with new ones? That hiss is probably the DC to DC converter, and if the electrolytic becomes noisy or leaky, the hiss might be at a high enough level to be noticeable.

 

[Liriel]

I got away the noise.
I build in These Sound board.
No noise after install

Gesendet von meinem Huawei P10 mit Tapatalk

 

[britain4]

I got away the noise.
I build in These Sound board.
No noise after install

Gesendet von meinem Huawei P10 mit Tapatalk

Can I just say thank you for this, I ordered the same one, it turned up with no instructions and I couldn’t find them anywhere!

It’s a great board, noise isn’t totally gone but even at max volume it’s quieter than before fitting it!

 

[Liriel]

I got the instructions from the seller after i ask for it.
My noise are gone at my 2 gba after install All These cables

Gesendet von meinem Huawei P10 mit Tapatalk

 

[Guy_Manley]

Sorry to revive an old thread but I've had this same issue with my GBA001 after adding an IPS v2 screen from FunnyPlaying and a lith-poly battery mod. As a result I'd never use head phones and I felt like I was annoying those around me while playing.

I got that jist that it might be bad capacitors so I replaced all of them. After replacing them my GBA still makes the same 60hz hum with overtones, Almost changes pitch when I change the screen brightness level. I've ordered a 5 pack of 220uF, 16V, 105 C caps and I'll attempt this next, seems like it's worked out well for others in the past.