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And so, fairly pleased with my finished track, I burned it to CD and took it up the Hotel so that Gaz could give it an airing. Unfortunately, what I didn't know is that Gaz's CD player only plays mono and this is how the track sounds in mono:
At first it sounds fairly similar until the first synth line comes in and you're thinking 'hmmm, that sounds a little low' and then when the vocals come in at a pathetically low volume compared to the bass and drums then you know something ain't quite right. And it's all to do with the mono system. The track above is simply the mono version of the original but when converting the track from stereo to mono, the synths and vocals have effects on them (reverb, flanger, chorus etc) which were done in stereo and 'mono-ising' them leads to phase-cancellation (or anti-phase). I knew about it this and I always make sure my bass and drums are mono but I never realised what such an effect it would have on a mono-played stereo track. I guess from now on I'll be checking my track in both stereo and mono to make sure it sounds ok in both, although having had a go on the youtube version I put up (YouTube is also mono!!!), it's not an easy task to get it good in both :(
Here's a more in-depth analysis of what's going from a forum post over at Dogs On Acid:
What's first important is to realise that stereo is, at its most basic level, a difference between the two channels. When one thinks about all the ways the two channels can be different, there's a lot of them. All of these contribute to 'stereo' in some way. To look at a few;
Volume: If you have a single sine wave playing equal volume, 50/50 in both speakers, it 'appears' in the middle. Now shift that 50/50 balance in favour of the left speaker - ie increase the amplitude on the left and decrease it on the right. Now we have say 70/30 and the sound appears to be coming from some way to the left. Shift the balance further to 100/0 and it sounds totally left. Simple, right?
Now when you collapse to mono (2 channels added together to make 1), what happens? In all cases you get back what you put in. 50 + 50 = 70 + 30 = 100 + 0 = 100. Sweet. That sound, all we did was change the relative amplitudes, and it panned. And when we summed to mono nothing was lost.
So that's getting an otherwise monophonic signal and throwing it over to one side. Logic suggests that a good thing to do would be to get another sound and throw that to the other side, which would help give balance and also width.
Phase: Phase is how far through its cycle a wave is. This is often expressed in degrees - one wavecycle is 360 degrees. A sine wave starts at -infinity at 0 degrees, reaches maximum at 90 degrees, goes through -infinity at 180 degrees, minimum at 270 degrees and back up to -infinity at 360 before starting all over again.
So, if we have our left and right speakers playing a sine wave in phase - no phase difference - the signal is the same on both sides. This means the overall result appears in the middle, just like before. Now we create a phase difference - make them not line up any more - by delaying the right side by 90 degrees' worth. Now you will get the impression something is different, although it will still seem to come from the middle. When you collapse to mono, you get interference.
What this means is that you add the two sides up and see what you get. In the volume example, it was a straight addition as there was no phase difference. But now we have the problem where sometimes the right is positive and the left is negative, sometimes they are both positive. When you put them together, there are times where they 'destructively interfere'. This is what anti-phase means, the two sides will subtract from each other at such points. Something will be lost at these times.
We can go even further and make one side 180 degrees 'out of phase' ie in perfect antiphase. You can see this here;
http://en.wikipedia.org/wiki/Image:...f_two_waves.png
There's nothing left! So this is what antiphase is.
But this is all physics, where's the musical application? As shown, you can use phase differences to make the two sides different. When these phase differences are distributed across many frequencies, one gets the impression of a big wide sound because the two sides are very different in a lot of different areas. It seems to fill the space and sound deep and big etc. However, if your sound is made mono for any reason, you run the risk of severe phase cancellation across a wide range of freqs - the two sides will subtract from each other. Internet radio, for example - your big sound will sound 'ghostly' and 'hollow' as lots of it gets cancelled. Another famous thing is out of phase bass causing problems in vinyl cutting, because the needle is trying to go in two directions at once.
So phase difference can be useful - it makes the two channels different and therefore creates width. But this will cause some antiphase (ie cancellation upon monoisation). The more and more phase difference you make, the more antiphase you get - the more you lose on monoisation. Some people do not give a shit about this because they are going to CD, and there is no physical reason not to do it, unlike vinyl ie, don't worry about it.
To finish, how to use this fuckin shit? Many mixes I hear are 'big mono' - everything is panned centrally but with lots of reverb/chorus/widening etc. It's not width like you hear in jazz where the trumpet's over there, and the sax is over here.
That's width from panning - no antiphase. But width from panning alone doesn't fill space. So for dnb, I'd suggest (IMHO!) that a judicious combined use of these two approaches will give width AND spatial fullness. And keep your mono button handy to make sure your mix is pretty mono compatible - you never know where it might get played back, and you want it to sound good everywhere!
So, lesson learned: Always make sure that your track sounds just as good in mono as it does in stereo before playing it out somewhere!!
until next time :)
