Famicom Disk System sound on an American NES

[superpope]

I hooked a FDS RAM adapter to a honeybee converter and loaded the disk version of Legend of Zelda on my top-loading NES just for the heck of it.  I noticed that the FDS specific sounds just don't play. 

I'm aware that the Famicom Disk System has additional sound capabilities, but why are these sounds missing when the FDS is paired with an American NES?  Is the chipset in a US system simply incapable of interpreting the data?

Just curious...I told my son I'd try to find out.

[son_ov_hades]

I don't know the tech of it, 133Mhz will help with that I'm sure, but it has to do with the expansion port on the NES. The hardware to deal with the extra sound channels is located in the expansion port, which I'm guessing means they originally wanted to make a FDS that connected there and didn't use a ram adapter. Apparently you can mod the NES to use this though, but I'm not a tech person at all. 

[133MHz]

There was a quite comprehensive thread in this board where this issue was discussed and michaelthegreat, UglyJoe and me were able to come up with a relatively simple mod for getting expanded audio into your NES. It involved fitting a resistor + capacitor inside your pin converter and bridging two pins in your NES motherboard, I even posted a pic of mine, but I can't quite find it right now .

When one of the mods see this thread, hopefully he will find the appropriate one and move this whole thing over there.

[UglyJoe]

Here's the thread 133MHz is talking about:

http://www.famicomworld.com/forum/index.php?topic=1860.0