Questions about Nes Audio Modification

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Questions about Nes Audio Modification
by on (#32183)
Hello everyone.

I've just seen this topic:

http://nesdev.com/bbs/viewtopic.php?t=182

And i've got a question about the third modification:

http://www.54.org/sage/condev/NESMods/NESMods_Sound_Input_On_Pin_18.jpg

All i want to know is:
-Does anyone have done this modification to be able to play "sound extended" famicom games?

-After this mod, does the original Nes games still work without putting a switch?

-Is there an easier method for someone who have dificulties in soldering?

Yes i know, buying a famicom/famiclone is the best way so the last question:

-Does anyone have a list of famiclone which are "extended audio" capable?

Seems like the Generation Nex is, but i want someone to confirm.

EDIT: the Sachen Q-Boy is i've seen a video on youtube.

Thanks in advance. :wink:

by on (#32203)
Iirc it should stil function 100% normal cause you basicly just "extending" whats already there. and it doesn't have anything to do with the games, really. Yup the extended audio wil work then. But only on the famicom games that supported it. Remember you solder the wire from the expansion port to the famicom adapter.....not the cart slot.

by on (#32205)
Okay, Thanks for your fast response. :D

I'll try this when i'll got time (and the capacitor/resistor needed). :P

by on (#32207)
I've done the mod for playing my Just Breed cart and it worksed fine. At first I messed up and soldered a resistor too low, and the volume of the extanded sound way way louder than the volume of regular sound.

Other carts will work 100% fine and are completely unafected by the mod. Maybe it adds noise to the sound sometimes, I don't think it's significant.

Carts that would need it : Lagrange Point, Just Breed, Castlevania III (J), Gimmick, etc....

by on (#32216)
Bregalad wrote:
Carts that would need it : Lagrange Point, Just Breed, Castlevania III (J), Gimmick, etc....


That's why i want to do this mod, i've just bought Lagrange Point (VRC7) and Sangokushi 2 (NAMCO106).

Last Question:

Quote:
Remember you solder the wire from the expansion port to the famicom adapter.....not the cart slot.


I don't really understand what Jeroen wanted to say.

It's just that i need to solder a wire on my nes/famicom adapter from the Famicom side pin 46 (sound out) to NES pin 18 on the adapter, right?

by on (#32217)
Right.

by on (#32218)
Okay, Thank you very much.

by on (#32259)
Jeroen wrote:
Remember you solder the wire from the expansion port to the famicom adapter.....not the cart slot.

Why tether the cart adaptor to the NES by soldering a wire between them? I just wired the expansion port's sound input pin to one of the unused pins in the cartridge slot, and rewired the Fami adaptor to output the sound on that corresponding pin. You can't even tell they're modded.

by on (#32303)
Theres unused pins on there? (that aren't secretly meant for something else like those middle pins)

by on (#32366)
The middle pins were meant for use with the expansion port.

by on (#32371)
That was kinda what I was aiming for.........

by on (#32380)
While the modification for sound is usually done by using pin 18, the Nintendo-made MMC5 boards passes audio trough pin 55. Since a custommer NES usually have nothing connected to pin 55, audio won't do anything unless a wire is soldered on the expansion port (R/C circuit needed are already on the board).