So I have made great progress on removing the noise from the GBA console without any effect or removal of original audio.
I believe this is something nobody has yet done, so have provided a detailed article here https://retrosix.freshdesk.com/a/solutions/articles/77000361029
As its an ongoing thing and I am always looking to improve upon it, as well as get feedback on if it worked for you, and if you have any suggestions, or just want to say thanks, I created this post.
Any discussion about the noise issues on the GBA feel free to post here.
Also I sell the kit to amp the audio (https://retrosix.co.uk/CleanAmp-Audio-Amplifier-with-Speaker-All-GameBoys-p141361141), to remove the noise completely when volume is down [built into new CleanAmps so no need to buy separately after August 2020] (https://retrosix.co.uk/PureSilence-CleanAmp-Upgrade-Game-Boy-Advance-p207874600), and to filter the noise from all audio at any volume level, (including the headphone sound!) here (https://retrosix.co.uk/Dehum-Dehiss-Kit-Game-Boy-Advance-p217244008).
Super article ! Is it possible to use regular 1UF electrolytic caps instead or the smd ceramic caps ?
Ceramics are better, and I've not tested with aluminium ones so likely won't filter as well, but you could try. SMD soldering is super easy https://www.youtube.com/watch?v=Q5hEQJtadyo
I have seen another noise fix using a capacitor. It works by connecting one of the pins of the AMP to ground through a 6V 100uF capacitor. Have tried this before? Does it also work too?
Any tip on how to solder the extra capacitor on the CP1 capacitor pad (over current noise)?
No that article doesn't work at all. They are just grounded VRef. If anything that adds noise. No idea why they posted that. Perhaps they had an issue with a dirty volume wheel and instead of cleaning added that and in that circumstance maybe helped but its totally wrong and irrelevant fix.
For soldering to CP1, add extra solder to both pads first of CP1 so you have balls of solder on each, then place the other capacitor in place, bend legs to touching the solder balls and warm up to attach.
Trim the legs to right length first before soldering them on.
I managed to desolder the existing capacitator on C15 and loose it due to it being so tiny... Is it possible to replace it and what component is it?
Hi Luke, thank you for all the work you put into these things!
I read your guide about fixing the audio issues and I have a couple of questions. I saw that in one of the pictures you added an extra capacitor to C6, but you don't mention this anywhere in the guide. Is it relevant?
Also, it is a good compromise to add just the 10 uF cap to C15 for simplicity, instead of 1+10 uF? It shouldn't make that much difference? It would just give a cleaner look in my opinion with only one extra cap attached.
Different question: what exactly is this "clean power board" that you mention in the guide?
Should be fine without original cap, the new ones will handle the capacitance.
The C6 isn't needed, I just added it while testing effects and made no difference, that power rail is never overloaded so you will gain nothing at all from adding to C6.
No, it needs 1uF and 10uF. Each supply power during different speeds of transient loads (LCD and CPU speeds differ) so both are the best approach.
The CleanPower boards are my replacements for the power generation voltages for the consoles. I've made one for GBO and Game Gear. I will eventually make them for all consoles
I am in a similar situation as Oscar Bremer; I used too much heat and removed the original capacitor C15 and lost it (as well as the 10uF caps from the de-hiss kit); what can I get to replace the lost original capacitor? Thank you!