OK, got it figured out.  Here are the steps I took:

1) Use the line-in jack and record in Audacity, making sure that the recording input volume and the GameBoy volume are low enough to avoid clipping.

2) Normalize the track in Audacity so that it isn't super quiet.

3) Remove the background hiss using this method.  If there is no silence on the track for the noise profile, add some empty bars to the end (or beginning) of the track (the buzz coming from the GameBoy when nothing is playing is different).

Of course there's trimming and other editing steps you can perform, but these are the ones that I used to resolve my recording issues.

Thanks to everyone for your help!  Final track here: http://chipmusic.org/bschnur/music/down … ck-factory

Chainsaw Police wrote:

Every recording gets this. Gameboys, not being engineered for crisp, clear music, have artifacts in the recordins, a la the noise you're hearing. Either invest in a prosound, or EQ out the noise (I think Voc Road said it was 2.4 khZ or something, but don't quote me on it).

Either that, or learn to love the buzz!

Okay, I can do that.  But I want to clarify: is this something that happens specifically when recording, or in general?  Because it's not noticeable when listening directly on the GameBoy or through a speaker.

I have now recorded the track using the line-in jack, and the summing issue (assuming that was the issue) is solved.  (Thanks!)  However, now I've run into two new issues:

1) There's a slight steady level of noise in the background when the song plays.  It sounds similar to the noise LSDJ outputs when nothing is playing (which also gets recorded, though that's fine) but is happening during the song itself.  I will see what I can do with audacity after the fact, but would love to be able to get a clear recording so that the original sound isn't altered.

2) Though I wait a few seconds to play the song after I start Audacity recording, the song starts out a bit muted and fades in.  I'm not sure what causes this to happen, but am going to try waiting for a longer period of time to let Audacity or the sound card stabilize, or whatever.  I don't know if it needs to do that, but I'm new to this.  I'll post again when this fails, or doesn't.

UPDATE: This regards issue #2 above.  The volume seems to fade in (increase) as Audacity plays (that is, the position at which playback starts affects the volume of the playback).  If I start playback several seconds before the music starts, the song starts at the correct volume, but if I start playback at song start, it takes a second or two to reach full volume.

I'll try exporting it anyway and see what happens.

UPDATE 2: The exported file includes the fade in.  I'll play with Audacity effects/editing tomorrow night, see if I can fix it.

@kitsch: Not yet.  I haven't had a chance to get a new cable.

@Fudgers: I believe that using the mic-in jack was the issue. See my (upcoming) update for details.

@Jellica: Thanks, I'll try the line in tonight.  I believe it's a stereo cable, and since it sounds fine on the JamBox with the same cable, I'm inclined to believe the cable isn't the problem.  In case it comes to it, are there any external mixers you would recommend (or warn against)?

@RyuX: Thanks, but it's not a clipping issue.  I've turned the GameBoy volume and the recording volume down, and the dB level stays within Audacity's accepted range.

I have a song I intend to record, but different problems arise depending on the method I use to record it.

The first method I used was to connect my (classic) GB to my PC's audio jack (mic in), and record the song with Audacity.  I was able to record this way, but at several points throughout the song, some or all of the tracks become muffled.

I'm not a professional musician, and don't know the actual term for how it sounds.  Flange perhaps? Here's a link to the song in case you want to hear what I'm specifically talking about (an example of the muffling is at 2:12): http://chipmusic.org/bschnur/music/down … ity-issues

The song sounds fine on the GameBoy, as well as when I connect it to my JamBox using the same cable, so I assumed it was either a sound card issue or an issue with recording via the audio jack or with Audacity.

The next thing I tried was to transfer my save file onto the PC and record using BGB.  I was able to record, but the sound is stilted and choppy.  I played with the options in BGB, recording tracks separately and not, halving framerate during recording (not sure what that actually does), but wasn't able to acheive an acceptable quality of recording.

Next I moved on to try KiGB (on my MacBook Pro).  The result had a more consistent tempo, though it was a slower tempo than the song on the GameBoy.  The sound quality was a lot worse than the other recordings, including a lot of infuriating clicks, and the entire song sounds a half-note flat.

Is there another easily accessible option that is tried and true?

As far as additional equipment goes, I'm not broke, but I don't want to spend money on anything I don't know will work.

Thanks for reading and thanks in advance for any help or advice you can provide.