Humming sound on Super Famicom

[ShutokouBattle]

I had a thread somewhat related to this long ago, but I think this problem is sufficiently different that it merits its own thread.

I have an SNES SCART cable that I use with my Super Famicom. On one of them the image is flawless, and on the other the colors are wrong and there's noise, but that's not the point. On both of them there's a faint humming sound over the audio. At first I thought this was because the audio wasn't grounded on one of them, but I fixed that problem and I still hear the humming.

It seems like the video must somehow be causing interference with the audio, because the humming gets louder when there are lots of bright things on the screen. I connected an audio passthrough to it to make sure it wasn't a problem with the adapter I'm using, and I still heard the humming. I tried using a regular composite cable with stereo sound and it didn't have any humming, so it seems specific to SCART cables.

I read on this page - http://www.videogameperfection.com/scart.php - that this is a common problem with console SCART cables, but I don't really see any way to fix it. I can't sacrifice high-quality audio for high-quality video. Any ideas?

[Fudoh]

build a new cable using a better cable. Use multi-coax cables with seperate shielding for audio and video. It's really just a cable quality issue.

[ShutokouBattle]

I really don't want to build another cable. I just finished building one, and I really don't want to go through that again. Not right now, anyway. Isn't there somewhere I could buy a better quality cable? Also, why does this happen with my SFC cable but not my Saturn one?

[Fudoh]

The original japanese Nintendo SFC cables are good, also the european Nintendo Gamecube RGB cable. The SNES RGB signal seems to have a big portion of high frequency which causes interference on the audio signal. It's a known problem and you might call it a design flaw (compared to a system like the Saturn).

[neorichieb1971]

You could try putting a breakout cable between the snes scart and the TV. You would need another form of amplification though.

[ShutokouBattle]

The European GC SCART cable works with a Super Famicom? I assume you mean the official Nintendo one, right? Or does it matter?

Also, the official SFC RGB cable is Japanese RGB, correct? So I'd need an adapter to connect it to a SCART input. Or I guess I could modify it... but that could be rather complicated as there ought to be resistors and/or capacitors inside.

[Fudoh]

The European GC SCART cable works with a Super Famicom? I assume you mean the official Nintendo one, right? Or does it matter?

yes, yes & yes.

Also, the official SFC RGB cable is Japanese RGB, correct? So I'd need an adapter to connect it to a SCART input. Or I guess I could modify it... but that could be rather complicated as there ought to be resistors and/or capacitors inside.

yes, it's got the japanese pinout, but it's easy to modify - just a matter of unsoldering and resoldering a few of the scart pins.

[MKL]

You can also mod the system with separate stereo jacks so you can make a scart cable that only carries video to avoid cross-talking with audio:

http://img367.imageshack.us/img367/8908/19962017lj8.jpg
http://img367.imageshack.us/img367/4966/20935882oo6.jpg
http://img367.imageshack.us/img367/3416/jjxg7.jpg

[evil_ash_xero]

Necro bumping this thread.

I have 3 SNES systems, and they all have this buzz thing going on. The mini I just got RGB modded has it a little worse, but they all have it.
They do not have it through composite, with official cables. So, this is just a cable problem? I could try and hunt down some official SCART cables, but I don't want to go through the trouble, if the issue isn't gotten rid of close to completely.

Are the Retro Gaming Cables cords good enough? They're out of stock, but I'm assuming they'd be in stock at some point.

[ApolloBoy]

So, this is just a cable problem?

Yes, a lot of third party SCART cables aren't properly shielded so you'll get audio buzzing. The Retro Gaming Accessories cables shouldn't have this problem since her cables have plenty of shielding.

[evil_ash_xero]

Does she have a web site, rather than her Ebay store? .

[ApolloBoy]

Does she have a web site, rather than her Ebay store? .

She used to, but not anymore for some reason.

[speedlolita]

You can also mod the system with separate stereo jacks so you can make a scart cable that only carries video to avoid cross-talking with audio:

http://img367.imageshack.us/img367/8908/19962017lj8.jpg
http://img367.imageshack.us/img367/4966/20935882oo6.jpg
http://img367.imageshack.us/img367/3416/jjxg7.jpg

This is quite a beautiful mod IMO.

[evil_ash_xero]

OK, one last question on this one.

If I have stuff hooked up via composite, with the official cables, there is no hum at all.
But with the SCART, I get the humming.

Is this a 100 percent way of knowing it's the cables?

May sound like a dumb question, but there's always someone who will pop their head up and say "oh well, there is this instance where SCART is known to have problems with yadda yadda yadda". It's like clockwork.

[ApolloBoy]

OK, one last question on this one.

If I have stuff hooked up via composite, with the official cables, there is no hum at all.
But with the SCART, I get the humming.

Is this a 100 percent way of knowing it's the cables?.

It pretty much is the SCART cable, since you have a bunch of other signals running right alongside the audio signals within the same cable. If you don't have proper shielding for each wire inside the cable, you're going to get interference problems like audio buzzing. It's even worse if only one or two ground wires are connected inside the SCART end; connecting every single ground pin within the SCART end helps but it won't totally eliminate the problem.

[Eretro86]

Hi I'm having a similar problem with my super famicom. I have it connected to a crt via gamecube rgb and using a mega drive power supply. When I turn the volume up to a decent level I get distorted sound effects making a crackling sound.

I was wondering if this is a fault on my particular super famicom or a flaw of the system in general and whether the RCA out mod shown previously will improve the sound quality.

Any advice much appreciated cheers.