another mono vs stereo question

[canadave]

I'm a bit of a beginner at sound/recording theory, so please bear with what must be my painfully obvious ignorance on this subject

My understanding of mono tracks vs stereo tracks is that mono tracks route all sound equally to L and R channels, period--that's it. Whereas stereo tracks allow you to do the same thing, except also optionally route different amounts of sound to the L or R channel at different times.

If that is correct, then why would I ever create mono tracks, since a mono track in that case is no more than a subset of the possibilities of stereo tracks? When setting up tracks to record in Logic, why wouldn't I always use stereo, and then if I don't need to use the extra stereo capabilities of the track, I simply leave the sound alone as a "faux mono" track (in other words a stereo track with sound equally sent to L and R channels)?

Or am I missing something here?

[ski]

Mono audio is one "channel" of audio signal which, when played back in a mono channel strip is automatically routed to the left and right outputs equally if the pan control is set in the center. Moving the pan knob has an obvious result.

Stereo audio is comprised of two entirely separate audio channels played back simultaneously: a left channel and right channel. Usually these two channels of audio are interleaved into a single audio file, ad when that file is played back, the left and right signals are separated. The left signal is mono, and the right signal is mono. Together they produce stereo IF there's a difference between the two signals. For example...

Let's say you have a stereo recording of birds chirping in an open field, with the mics spaced 100' apart. A bird chirping closer to the left microphone is not going to sound as loud in the right microphone, and vice versa. It's the difference in signal between left and right recordings that produces a stereo image. The sound picked up by the left mic is mono, as is the sound picked up by the right mic. When played back simultaneously you have a stereo recording.

HTH.

[canadave]

Thanks very much for the quick reply...I'm not entirely sure it clears up my question though.

Mono audio is one "channel" of audio signal which, when played back in a mono channel strip is automatically routed to the left and right outputs equally if the pan control is set in the center. Moving the pan knob has an obvious result.

I'm afraid it's not obvious to me (remember, I'm a beginner here). I would think moving a pan knob on a mono signal has no effect on the sound, am I right? Or, are you saying that the pan knob can indeed move a mono signal so that it sounds like more is coming from the left speaker, or the right speaker?

Stereo audio is comprised of two entirely separate audio channels played back simultaneously: a left channel and right channel. Usually these two channels of audio are interleaved into a single audio file, ad when that file is played back, the left and right signals are separated. The left signal is mono, and the right signal is mono. Together they produce stereo IF there's a difference between the two signals. For example...

Let's say you have a stereo recording of birds chirping in an open field, with the mics spaced 100' apart. A bird chirping closer to the left microphone is not going to sound as loud in the right microphone, and vice versa. It's the difference in signal between left and right recordings that produces a stereo image. The sound picked up by the left mic is mono, as is the sound picked up by the right mic. When played back simultaneously you have a stereo recording.

Right, but how does that influence the choice of which track to use in Logic?

Again, I'm not understanding why, with any given instrument, you would not simply always use a stereo track. Then, if you want to later do some kind of stereo panning effects (say, make a piano sound like it's sweeping from left to right), you can do so. And if you don't want to sweep the piano, and just want it to sound like a standard mono signal coming equally from left and right, you can do that too. Why would I ever "limit myself" and choose a mono track, is my question?

[ski]

...are you saying that the pan knob can indeed move a mono signal so that it sounds like more is coming from the left speaker, or the right speaker?

Yes.

You should try it for yourself. Audio stuff is much easier to hear than to explain:

1) record a vocal or spoken work on a mono audio track
2) play it back and move the pan pot around. The result will be obvious.

..... I'm not understanding why, with any given instrument, you would not simply always use a stereo track.

Because not all instruments are stereo. Take vocals, for instance...

[canadave]

Okay...a fair point So, though, for something like multioutput Ultrabeat, which creates mono and stereo tracks...which should I use?

[Rev. Juda$ Sleaze]

Hi canadave,

It sounds like you're missing an important part of the puzzle. Even though you are correct that mono sources have no left/right difference, they are still routed to your stereo ouput, so if you pan a mono track, it will move left and right.

It is often easier to get mono sources to fit easily into a mix, because in simple terms they don't have width (but that's not to say they can't sound "phat"!). It's also worth noting that with stereo sources, the pan pot doesn't actually pan the sound, it acts as a balance control (making left/right quieter or louder), so if you want to pan stereo sounds use the Direction Mixer plug-in.

As for if you should use stereo or mono outputs for UltraBeat, well that depends entirely on you! There are no rules. Although many people like to keep their kicks and snares mono.

Again, as Ski has already said, the best way to figure it all out is to experiment. At the end of the day, we'll only be trying to describe what you could hear for yourself.

[canadave]

Excellent, Rev, thanks for clearing that up! I did not at all know the bit about a pan pot being a balance control rather than a stereo panner.

I hear what you're saying (no pun intended!) about there being no rules, try it and hear how it sounds for myself, etc...I guess I'm just asking what the "best practices", or "usually followed norms", are for instruments in terms of whether to record them stereo or mono...and why that would be so. For instance I *have* heard before that vocals are usually recorded on mono tracks...I guess that's not a hard and fast rule, but it's something most people do, because it's a mono signal, and if you recorded it onto a stereo track, you'd have a doubling effect of the sound of someone's voice, which would sound weird. (right?). So when you say "many people like to keep their kicks and snares mono", I've heard that too...out of curiosity, why is that?

Hi canadave,

As for if you should use stereo or mono outputs for UltraBeat, well that depends entirely on you! There are no rules. Although many people like to keep their kicks and snares mono.

Again, as Ski has already said, the best way to figure it all out is to experiment. At the end of the day, we'll only be trying to describe what you could hear for yourself.

[Rev. Juda$ Sleaze]

Well, vocals are very often made up of layered takes, rather than just one recording of a person singing. These tracks will often be panned to make the vocal spread across the stereo field. But recording vocals with a pair of mics to get a stereo signal doesn't produce any weird "doubling" effects, and there's nothing inherently wrong with stereo vocals.

As for drums, with acoustic kits usually the overhead mics will be a stereo pair, and the other kit pieces will all be mono (even though there will often be top and bottom mics on the snare and 2 or 3 kick mics). For electronic kits, and particularly in tracks intended for playing in clubs, the kick especially will be mono and dead-centre. This is for a bunch of reasons, but not least because club PAs are summed to mono, so you want that kick to still come through big and strong. Sometimes the interaction between left and right channels can make a sound thinner and weaker. Checking your mix in mono by placing a Gain plug-in as the last insert on your stereo out channel and clicking the mono button can be a useful exercise to see if your mix is abusing stereo coherence.

Very basically, and with many caveats, if you want a sound to fill the whole field, have it mono and dead-centre. If you want a sound to come from a specific place in the stereo field, have it mono and pan it. If you want a sound to occupy a range of the stereo field, have it stereo and use the Direction Mixer plug-in to move it around the stereo field (though this will only work if you are starting from a stereo source, ie. a recording with different left and right channels. you can't take a mono kick sample and somehow make it stereo... well you kind of can with some trickery, but it will never be the same as a stereo recording). One method to have a big wide sound is to take two slightly different mono sources - say you've got a synth hook, you replicate the track and change the sound on one of them (slightly different filters, more distortion, whatever), then pan one hard left and one hard right, this gives you a nice fat wide sound, but still with room to slot other instruments in the middle.

Time to start playing!

[canadave]

Now THAT is all perfect info I can understand and use. Many thanks!!

[Rev. Juda$ Sleaze]

You're welcome canadave

[Facepalm]

Because not all instruments are stereo. Take vocals, for instance...

Nonsense!

All sound is stereo because we perceive it with 2 ears.
If we are deaf in one ear all sound is mono, and if we had 4 ears it would be quadrophonic.

[Rev. Juda$ Sleaze]

Because not all instruments are stereo. Take vocals, for instance...

Nonsense!

All sound is stereo because we perceive it with 2 ears.
If we are deaf in one ear all sound is mono, and if we had 4 ears it would be quadrophonic.

Nonsense!

You're confusing the source with the destination. We don't have two mouths on either side of our head. Sound comes straight out of your pie-hole. For all intents and purposes, that's a mono source. Just because once it reaches your ears you perceive it as coming from a direction, that doesn't make the source stereo.

[shivermetimbers]

Nonsense! All sound is stereo because we perceive it with 2 ears. If we are deaf in one ear all sound is mono, and if we had 4 ears it would be quadrophonic.

[Facepalm]

Let me clarify.
At source, sound is a vibration of air spreading out in 3 dimensions. It is essentially mono.
We only interpret it as stereo because we have 2 ears, and simulate this with 2 microphones to make a stereo recording.
If we only had one ear or microphone we would interpret and record it as mono.

Therefore whether a sound is mono or stereo is determined by the number of receptors, (ears or microphones) not the source.

[Scott Jackson]

My dog has two tails.

I only have one eye.

Yet I perceive two tails.

Crazy!

[triplets]

Does this mean we need 7 ears to perceive surround?

[Rev. Juda$ Sleaze]

Let me clarify.

That didn't clarify anything, just muddied the waters.

Binaural mics get close(ish) to how we hear, but most stereo recodings do not simulate how we hear at all, they are gross distortions of it. Imagine a few typical stereo mic setups, now imagine ears in the mics' position and facing, then imagine what head shape a person would need to receive sound in the same way. Let's not even get into up/down locating as well as left and right.

Not many people are making mono records these days, so even if you record something in mono you're still placing it in a stereo field, which is closer to how sound works in the real world (unless you're talking about field recordings of planes flying over cities or mile-long trains passing by) than artificially wide recodings being panned around the stereo field.

Therefore whether a sound is mono or stereo is determined by the number of receptors, (ears or microphones) not the source.

If your argument is true, why do people bother with 5.1 surround? Surely, by your logic, if we have but two receptors, we could only ever interpret that as stereo?

[Facepalm]

How can a sound be stereo at source?

Impossible!

[Rev. Juda$ Sleaze]

How can a sound be stereo at source?

Impossible!

Who said anything about sounds being stereo at the source?

But, while you mention it... stereo speakers?