Saturday, October 13, 2012

Game Boy Color Loud Sound Mod

Update: new version available for order http://blog.avrnoob.com/2014/02/new-enhanced-gameboy-color-loud-sound.html


Update: published schematics and pcb design files for Eagle and Gimp. Make your own pcb and respect the license =) Take a look: http://code.avrnoob.com/gameboy-color-quality-amplifier/


Recently I've got used Game Boy Color and noticed lack of sound volume, it is barely audible. So I tear it down and pulled speaker out, it was all rusty.


 I had a speaker for Motorola L7/L6/L2/L71/K1-GSM/V8 on hands and soldered it in. So this is fixed sound. But it is still not loud at all, so low volume, I had to use my headphones instead. Oh and there is loud hiss noise, guess it's coming from power supply. I had to do something with it =)
I looked in my parts bin and spotted TPA2000D1 - a class-D mono amplifier from TI. It is 2W power rated with programmable gain and class-d is pretty efficiency means low power consumption.
After some time pcb was made.

I used schematics from datasheet but in the final version I changed 1uF bypass cap and other 1uF caps to 10uF and added 0.1uF. Also I had to change 120k resistor in oscillator circuit to 180k to keep frequency below 300 kHz, it was 330 kHz with 120k resistor.

Powered up ok first time wires connected and sound now is much louder even with gain of 6 dB but then I set it to 12 dB by moving one resistor to outrun any ambient noise. This is max before clipping I guess. Unfortunately noise hiss did not gone away and become even louder on high volume, so this is power supply. Game Boy Color is powered with two AA batteries. But it has switching step up power supply with 15V and 5V output, this makes noise because amp is powered from 5V. I had to add additional 470uF cap to 5V power rail to make noise go almost away, now it's barely audible on max volume.

Amplifier pcb moved over speaker and case closes nicely.

Amp barely visible inside. This Game Boy Color now definitely has Hi Fi sound =)

17 comments:

  1. Nice job and very inspiring. Where did you source the tpa2000d1?

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    1. Thanks. Got it as samples directly from TI a while ago.

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  2. Nice mod, but is your amp only mono? Because the gameboy is stereo on the audio jack connection.

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    1. Thanks. This mod is for speaker only, and amplifier is mono indeed. But it's not harder to add headphones amp too for cleaner sound =)

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  3. Hey Avr Noob,
    Awesome work with the amp! I was wondering if you might be able to shed a little more light on the de-hissing caps you added?

    I know this would come in very handy with other gameboy models, even ones with 'prosound' mods already in and the like.

    Up the scene!

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    1. Prosound is just a line out I guess? No hiss there I hope =)
      Most useful cap here is that big black thing on 5v rail, you can see it on pictures. It is 470uF but bigger is better. I just can not fit bigger size inside the case. I installed 16v rated cap but 6v or 10v is enough and it's smaller, so you can install bigger capacity cap. It filters power supply switching noise and spikes and provides some power buffer when using amp on max (if you see red led blinking on max volume you need this cap). And better use low esr caps. Nicer solution is to change default 100uF aluminum smd cap, which you can see under new black cap, to bigger if you have. Probably it could just dry out after those years.

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  4. Any chance to get that pcb? An image to make my own? Thanks.

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    1. Why not. Just updated post with link to schematics. Take a look at the top.

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  5. Is anybody selling these amps? I'd be interested in buying one.
    Great work. Thanks for sharing!

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    1. If there is a demand in quantity I can definitely make a kit or assembled pcb kit.

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    2. You should try to cloudfund that pcb or start accepting donations. I would love to spend some money on this nifty piece of hardware.
      Or maybe talk to kitsch-bent, he seems to be very open-minded for gameboy-improvements, plus he runs a shop to sell stuff like that...

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    3. I sourced the IC and a nice adapter-board (I live in germany)
      http://de.farnell.com/roth-elektronik/re933-03/adapter-smd-tssop-16-0-65mm/dp/1426182
      and
      http://de.farnell.com/texas-instruments/tpa2000d1pwg4/power-amp-class-d-audio-smd-2000/dp/1207309

      I'm pretty confident in my soldering skills but I lack the knowledge of electrical components - plus I can't use the pcb layout files that Anton kindly shared... May I ask for a rugh diagramm or plan along with the resistor and caps values? I do like spending time with old electronics and improve game consols, but bottom line is: I'm a n00b and in need of a n00b-friendly guide.

      Anton, please add a donation button to your site.
      Thanks again!

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    4. Alex, you should download Eagle CAD and open sch file I shared, and you will see schematics with values. Then there is old values for caps, basicly you need to change every 1uF to 10uF and change C8 to 0.1uF. Schematics is based on one from datasheet which I linked in the post. Eagle will show brd file for you aswell.

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    5. I found nice amplifier from Analog Devices which is smaller and needs less components. So I will try to make a pcb small enough to fit in the corner just above speaker, not sure if GB speaker is ok for this mod, because mine was dead before the mod. If test goes well, I can make some kits for you guys.

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    6. Update http://blog.avrnoob.com/2013/07/gameboy-color-quality-sound-mod-update.html

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  6. I see that you did only use one channel (left) of the potentiometer for the speaker. As the sound indeed is stereo, you may want to mix both channels into one mono channel for the speaker. (As if the software wants to output stereo, you still get both signals over the speaker)

    I did also made a louder sound mod using a TDA7052 in my DMG. What I did to get a fully mono channel is to decouple both left and right channels using a 100nF non-electrolyte capacitor on each one before mixing them together. I don't know if this would be the preferred way to do it, but I think it works great.

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    1. Well, I used left, because, as I know, when stereo started to appear in devices they used left channel for mono signal. For example if you listen fm radio and want mono, it would be left channel =) But yea, in this mod both channels may be mixed. Check out my last post for new pcb for this mod =)

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