Mod NES for powerpak FDS sound with ON and OFF switch .

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Mod NES for powerpak FDS sound with ON and OFF switch .
by on (#46096)
Here is a mod for adding FDS sounds to NES when using powerpak with ON and OFF switch. 47k resistor mounted under NES inside expansion connector bay.

See video for step by step instructions.

http://www.youtube.com/watch?v=9Z507PxcLjs

by on (#68703)
Why would one need an on/off switch for the resistor? If left connected permanently (with no switch) would there be any conflicts or problems with normal NES carts?

by on (#68731)
I did this mod to my NES, and the 47k resistor mod is inaccurate in regards to sounding just like a famicom. The extra sound channel comes out way too loud. What I would recommend is placing a variable resistor (potentiometer) on the two pins. That way, you can adjust the strength of the sound wave to your liking and have a much better shot at it sounding like an actual famicom.

by on (#68732)
nothingnew wrote:
I did this mod to my NES, and the 47k resistor mod is inaccurate in regards to sounding just like a famicom. The extra sound channel comes out way too loud. What I would recommend is placing a variable resistor (potentiometer) on the two pins. That way, you can adjust the strength of the sound wave to your liking and have a much better shot at it sounding like an actual famicom.

That only tells that loopy hasn't measured the exact volume levels, but remember that they can be adjusted on the FPGA (mapper) side too. So what I would advice is to go with the "standard" 47k and inform loopy about the correct volume levels and hopefully he can adjust them in the mapper for all of us.

by on (#68733)
Well if anyone could make accurate tests with a real FC and FDS this would be awesome, but I imagine most people lacks these pieces of hardware :(

by on (#68754)
I added the 47k resistor to my NES today and played some Doki Doki Panic. I've never played it on an actual FDS, but it sounded just like it does when I play it on an emulator.

by on (#68759)
I used a 56k resistor because I could not find a 47k in my pile o' resistors. Sounds just fine as well.

by on (#68761)
Could there be some other variables that could cause my NES to sound louder? For example soldering job/console revision?

Edit: I also haven't tried the 1.34 mappers yet.

by on (#68774)
I'm using v1.34 mappers. You should update to the current versions and see how that sounds for you.

I read on another forum, BunnyBoy suggested using a pot instead of a resistor so you can dial in the sound level. Personally, I don't want to add a pot to my NES, but it would be a good idea if you want to make sure the sound level is perfect. Also, you could adjust it if a future mapper version tweaks the level.