Los Angeles, CA

I find it difficult to believe that no one has thought of this before, but I couldn't find a thread on this, so here goes.
I had been having great difficulty mixing vocals/other instruments with my tracks. I refused to give up my hard-programmed stereo effects, but using the phantom center created by mixing with stereo recordings meant there was no room for anything else in the mix. I decided what I really needed was an LCR mix- 3 mono tracks- left right and center. In setting about to do this, I also found a way to easily eliminate the noise floor without using any special plugins- just a bit of LSDJ work and patience. With this, I'm now mixing my next album with an average of 8-10 channels of layered audio from my GBA SP and the noise floor is still not noticeable.

Here's a demo: … uction-lcr

There is much for me to teach you, but first, know ye this: ... The following WILL NOT REALLY WORK on a DMG... sorry.
(NOTE: I judge this having tested it with a backlit DMG. Someone else is welcome to try with a unmodded one.)
I use a GBA SP. Thanks to the assistance of the one and only KoolSkull, I am confident that this will also work on a GBC.
Here's where everyone says, "But wait! Those are the noisiest gameboys of all!" Shut up. Pull up a chair... oh?... well go get a second one.

For those who do not know, almighty science tells us that if two sounds are played simultaneously, but one of them is inverted, whatever waveforms were identical in both sounds will be nullified. Any waveforms going up will be met by an identical waveform going down. These mirror images will cancel one another out. The background hum produced my the GBC and the GBA SP is almost completely identical in both the left and the right channels. So, if you isolate the noise on one channel, and the part of the song you want to record on the other, you can invert the noise right out. (The background noise of the DMG I tested was different enough in each channel to make this not really worth the effort)

Your task is simple. Open your song. Go into your instruments and set all of their output from "O: LR" to "O: L-"
Now your entire song is coming out of the left channel, and the only thing coming out of the right channel is background hum.
Record both channels. Now, in order for this to work, both channels must be recorded at EXACTLY the same input volume. Resist the urge to turn up the gains on your inputs. Keep them all the way down. This is the only way to ensure that your recordings will be exactly the same on each side.
You now have  one channel of music and one channel of background noise. Invert one of the channels. (Every DAW has an invert function. If you don't know where it is, find it and make friends with it.)
Now play back both channels panned to 0. You will notice that when you mute and unmute the noise recording that its presence is REMOVING noise, not adding it.
Now bounce that shit together in mono, and the noise is gone.

Hunker down. This is gonna take a while. (Still totes worth it, bro.)
Same idea, but... x3. In essence, you are going to make an LCR of your song. You are going to record JUST what plays in the center. Then you record JUST what plays on the left. Then you record JUST what plays on the right. By the end of it you will have 3 CLEAN mono recordings.
Go through your entire song- phrases, tables, and instruments, changing every instance of "O: L-" or "O: -R" to "O: - -" This will mute all of your panning effects.
Now go back through the song and change every instance of  "O: LR" to "O: L-"
You now have the mono parts of the song isolated onto the left channel, and only background noise is coming out of the right. Record and process them as instructed in the previous section. This will give you a clean, mono recording of your center stuff.... "C"

Now reload the original song and do the opposite- Mute all the mono parts of your song by changing all instances of "O: LR" to "O: - -"
I HIGHLY recommend you save a copy of this stereo-effects-only version of the song at this point.
Now go and mute all the "O:L-" and record just the stuff on the right. Record both channels and invert as instructed. This will give you a clean mono recording of all your right stuff. "R"
Re-load the stereo-only copy of the song and mute all the "O: -R". Now you're recording just the stuff on the left. Record both channels and invert as instructed. This will give you a clean mono recording of all your left stuff. "L"

You now have a clean, mono LCR of your song. Sync the three recordings and pan accordingly.
(I done hear of a lot of people using midi sync to ensure that their playback stays the same each time... I don't... I'm guessing that's another shitty thing about the DMG? All I know is my SP recordings are exactly the same length each time I play a song.)

Sound like a lot of work? Meh. Not nearly as inconvenient as programming an entire song onto an outdated handheld gaming console. You can do it. When most of my O commands are done in the instruments and tables, it doesn't take very long to change out... When i do a bunch of O commands in the phrases and I have to go through the entire song repeatedly.... yeah it takes a bit.

With the noise floor all but removed, you can record it all separately and pan each channel. You now also have the freedom to pan the C of your instruments off-center while keeping the L and R hard left and hard right- the way god meant them to be! You can go as crazy as you like recording things separately, but an easy place to start is recording the Center portion of each channel separately, and recording the L's all at once and the R's all at once. This way you can pan the Centers of each channel to a different space and keep the L's and R's hard left and hard right.
I record a lot of the channels' stereo effects separately from one another, but I'm insane... so there's that.
The problem I was having with mixing gameboy recordings before was the issue of the phantom center- Everything that SOUNDED mono was actually being produced by equal amounts of sound being played left and right. This means that the sound wasn't occupying just the center, it was occupying EVERYTHING. This is why I was finding it impossible to mix my gameboy stuff with ANYTHING else. But with this LCR method, the center channel is an actual factual mono recording that leaves room for other additional instruments without making everything sound like mud when it all hits the limiter.

There. You may now record your channels separately and cleanly, leave room for vocals or additional instrumentation, and keep all your badass stereo effects. You are welcome. Spread the learnin'.

Gosford, Australia

awesome work and very well explained! having said that, i'm going to try to find a way to do this without making seperate versions for each channel in LSDJ. sonalksis stereotools ahoy!


this might be a ridiculous suggestion, but would it be possible to do just two recordings: one from the gameboy with the track playing, and one with JUST the hum (without the song playing back)?

Assuming the hum is pretty constant, inverting the signal of the hum track should be able to cause phase cancellation of the background noise on the original track still too...

this seems far too simple to actually work, but I don't have time to test it right now. what do you all think?

EDIT: I mean for doing full, stereo LSDJ tracks. I don't think your technique for mono tracks can get much easier!

Last edited by Kedromelon (May 3, 2012 12:37 pm)


^ I'd do this if that works; but if not; might you be able to skip the whole "pan every instrument to the left with O commands" by simply panning the entire channel to the left (B + Left on the song screen)? That would save time. This is cool by the way; but honestly I'll just stick with my pro-sound DMG, it's got low enough noise.


whoops now that I'm way more awake I just realized why my idea won't work

(would be practically impossible to get the waveforms to line up correctly for full phase cancellation with my idea)

Last edited by Kedromelon (May 3, 2012 5:25 pm)

San Angelo, TX



Of course it works! I have a question though : doesn't that mean the hum noise background waveform is some kind of a constant value or pattern?

Los Angeles, CA

Syn: Sorry, there is no magic waveform that applies to all recordings. The noise you are using to cancel it must be recorded simultaneously as it is always a little bit different, as kedromelon said.
Zef: Yes, that would work as well if your song is mono.
Victory Road: By all means let me know if there's an easier way! haha PLEASE! smile

I should note that your Center mono recordings will lose any panning effects that you achieved through the use of the M command, but after recording this way, you can pan wherever you want, so who cares? Do be careful about this when recording, though- since you'll be pushing your song to one side you might want to make your M's the same value on both channels when you record the mono stuff.

Gosford, Australia

Okay so from a single stereo recording from a DMG I can get a mono recording which is JUST panned stuff and a mono recording which is only the "center"... I think. Of course, the panned stuff is both channels and I don't think it's viable to separate that recording into L and R. Still, baby steps!

I had an idea while messing around with sidechained phase inverters but I lost it - should come back to me the next time I do my business!

Los Angeles, CA

Yeah, you can get JUST the stereo stuff through inversion, but that's all lumped mono instead of L/R... I discovered that first and thought "... there's something to this... I just don't... know... What it is..." hah
I don't think I was able to isolate just the mono stuff this way though... cus if you invert one channel to get the stereo stuff, then part of that stereo stuff has been inverted, so if you try inverting THAT to remove it to isolate the mono, then it ends up putting it back in cus its been inverted twice so the inverted inversion in your inversion heard you like inversion dog and all that.

Abandoned on Fire

EDIT:  see next post

Last edited by egr (Jun 19, 2012 6:48 pm)

Ciudad de méxico, MX


Glad I've found this. I can confirm that this works like a charm on GBA advance using nanoloop 2.5.

Of course you need to manually pan all your patterns to one channel and the other one will of course only record the noise.

(You can copy your bank in nanoloop to an empty one so you don't have to sacrifice the original)