Help me understand mono/stereo

[Logicman991]

Alright, so i've run in to a problem recently. I thought i had a perfectly correct image of the differences between mono and stereo: Stereo is two channels(or outputs if you will), so a sound can come from two speakers with different volume on both to simulate the sound actually coming from a certain direction/place, while mono is just having the signals coming out from one channel - one place. Therefore, in mono it will not seem as the sounds are coming from different directions and thus making the sound more flat.

My confusion comes in here: I set up a software instrument in a DAW, specifically a synth, then i choose stereo... now the volume bar will be split into two parts on the channel strip, and if i pan it to the left i can see the sound getting louder on the left bar, weaker on the right, and in practice making more sound coming from the left speaker than the right, creating a vision in my head that the sound is coming slightly from the left - and this is the idea of stereo, right?...

But lets say if i now were to make a new channel strip and insert a new synth, only this time making it mono. Now the volume bar will appear as one, and not split like in stereo. And now lets say i'll pan it to left as i did with the stereo track. What happens? The sound gets stronger on the left speaker, and weaker on the right speaker. My question is of course: This is exactly what happens in stereo too, so what the heck is the difference?

 

[The Cancers]

Think of the ascending architecture of the mixer section of your DAW.
That is, all that's coming out of the speakers is what the master track (which, unless you press a button to switch it to mono, is always going to be sending a stereo signal) is sending to them.
The master track is composed of the mixed sum of all the individual tracks you have playing, mono and stereo.
So when you pan a mono track, it's being panned in the stereo field of the master track.
When you play a stereo track panned center, it sends whatever it has on the left side to the left side of the master track and whatever it has on the right side to the right side of the master track.
When you pan that stereo track (I'm gonna go ahead and caveat this next part with a very strong "I think." That is, I'm not entirely sure this is the way it works, but it's certainly something like this), you're really adjusting the balance of the two mono tracks that compose that stereo track.
That is, the individual stereo track is composed of two separate mono tracks which carry different but related information that gives the ears the impression - when they hear those tracks playing back from a stereo playback system - that they are hearing a single sound source in some particular space.
When you pan it left, you are turning up the left mono track that composes the stereo track and turning down the right one, thereby shifting the image of the space the single sound source is sitting in towards the left.

Stereo recording is the technique of using at least two mikes on a single sound source to give the above mentioned impression on playback of hearing that sound source in an actual space.

Stereo synths tracks generally make use of various artificial phase and other stereo-faking techniques to simulate a stereo sound field.
Not the same thing as stereo microphone recording, and information about location generally isn't carried by the stereo nature of the synth.

Any of that help?

 

[gecko zzed]

so what the heck is the difference?

Try thinking about it this way . . .

There is someone playing a piano you want to record.

You stick a mike in front of it, set up a mono channel and hit record.

When you play this back, you can pan the mono channel to the left or right, and the sound of the piano will, consequently seem to come from left or right. You might decide to have the piano panned partway left because you want space on the right for something else, e.g. a harp. So when you do a final mix in readiness to make a CD, you will have a stereo track with piano on left and harp on right.

But a piano is a very wide instrument, so instead of using a single mike on it, you might decide to use two mikes; one on the bass side, and one on the treble side, to get a more even spread of the sound. So you do this and record a stereo track.

When you play this stereo track back, you will hear more of the treble comng out one side (say, left), and more of the bass coming out of the right (and the middle notes coming from the centre. When you pan this track left or right, you wil shift this whole image to the left or right, but going left will accentuate the high, and going right will accentuate the low.

Recording something in stereo works best when the source being recorded is wide, e.g. a piano, a drum kit, a choir. When the source is narrow, e.g. a voice, a flute, a triangle, there is little difference between recording mono or stereo (and you may as well record in mono).

 

[Logicman991]

Hmm, ok, made things a little clearer but what about my example with the software synths? Whether i choose mono and pan it 30 right or stereo and pan it 30 right it doesn't seem to have different effects... they both seem to gain volume in the right earbud/speaker and lose some in the left... So whats the point of having the option to chose between the two in that case?

 

[Logicman991]

Stereo synths tracks generally make use of various artificial phase and other stereo-faking techniques to simulate a stereo sound field.

Sorry, overlooked that. So thats the only reason you have the option of stereo or mono on some synths?

 

[The Cancers]

Sorta, kinda, maybe.

Say you have a pretty good digital emulation of a piano.

As Gecko said above, you can get a much bigger and more realistic sound out of a piano recording with multiple mics.

So a pretty good piano "synth" (I've seen some out there that are supposed to be pretty damn good, though I don't really know whether they count as synths or sample players or what - I'm not really sure how you classify a "soft synth" like the new Alicia "Keys" VST) is gonna likely have that option for going stereo, and it's one you might often want to take because it's not gonna be just a mono track faked into stereo by phasing and other trickery.

A bass synth - meh, dunno why you would take a stereo option here if it's offered. Bass just doesn't get too much from being recorded in stereo.

So it's gonna depend on the synth and the source it's trying to emulate.

Mostly, though, it's gonna depend on the sound. If it sounds different when you have it in stereo than when it's in mono, then use whichever sounds best to you.
If it doesn't, then just go mono and don't confuse yourself.

 

[Armistice]

But a piano is a very wide instrument, so instead of using a single mike on it, you might decide to use two mikes; one on the bass side, and one on the treble side, to get a more even spread of the sound. So you do this and record a stereo track.

When you play this stereo track back, you will hear more of the treble comng out one side (say, left), and more of the bass coming out of the right

Hey gecko man... you're trying to perpuate this "everything is upside down in Australia" thing, aren't you..

 

[Chili]

Sorry, overlooked that. So thats the only reason you have the option of stereo or mono on some synths?

The softsynth (VSTi) needs to be able to generate a stereo audio signal to use it in a stereo track. I'm sure most do, especially if they incorporate some sort of delay, reverb or chorus effect. If it outputs a stereo signal, then you are going to hear different audio from each speaker when you have your stereo track centered. If you pan left or right, then you are only going to hear the left or right channel of the stereo signal, the other side will not be heard.

As an example, let's say your one softsynth is set up to generate a Flute and a Violin in stereo; the flute being on the left channel and the violin on the right of your stereo track. If you pan left, you would only hear the flute out of the left speaker and nothing out of the right. Iif you pan right, only the violin out of the right speaker and nothing out of the left. Now, let's say it's set up as flute and violin but as a mono synth. When you pan to either side, you will hear both instruments, but out of only the left or right speaker.

Does that help??

 

[miroslav]

Batter Up!

Lots of good point so far...but let me take a swing at this too.

Mono is a single point source.
Stereo is a L/R image/field.

Both can be panned and "appear" to have similar panning properties...but with mono you are only changing the location of a single point source, while with stereo you are shifting the entire image.

And yes...both mono and stereo WILL be heard in both left and right speakers to some degree unless either are panned hard to one side.

Also *true stereo* is not just something coming out of the left and right speakers. Sure you can take a bunch of mono tracks, mix 'em all up and create a final "stereo mix"...
…but *true stereo* is something you have to record as such, and then carry it through to the final mix.
You can combine true stereo tracks and mono tracks without issues...and IMO is a good way to go, as doing many tracks in stereo can be complicated...though one big-name engineer likes to work a lot with multiple stereo tracks -- Bruce Swedien (did most of Michael Jackson's major albums). He actually records most everything as *true stereo* tracks...but that takes a good deal of pre-production planning to pull off well in the final mix.

 

[The Cancers]

That's something I was trying to figure out how to explain, Miro.
I was thinking of emphasizing the difference between "stereo recording" and "stereo playback" but I think the True Stereo thing pretty much covers it.

 

[legionserial]

My personal preference is to use 2 mono tracks rather than 1 stereo track. Adds a little extra bit of versatility, and they can always be grouped into a stereo group if you want to control them as you would a stereo track.

 

[Dr. Varney]

The sound gets stronger on the left speaker, and weaker on the right speaker. My question is of course: This is exactly what happens in stereo too, so what the heck is the difference?

Going back to what you said earlier:

a sound can come from two speakers with different volume on both to simulate the sound actually coming from a certain direction/place

Yes A sound... and most stereo tracks will comprise more than one intrument/sound. In stereo, each instrument is placed (panned) into it's own 'position' in the stereo image.

Therefore, when you balance playback left and right, if the piano was panned more to the left and the bass were in the middle and your singer to the right then as you move the balance control left & right, you will get more piano or more vocal respectively, while the bass remains central.

If those instruments were not hard panned in the recording to begin with, you will hear a residual amount of each, left & right, respectively, as you move the balance.

The difference with mono is that everything's glued together. The balance control has different implications, depending on if the track were recorded in mono or recorded in stereo.

When you listen to an image that was recorded in stereo on a stereo amplifier, you'll hear whatever was placed left in the recording on the left speaker and whatever was placed right, coming out the right speaker.

When you listen to an image that was recorded in mono on a stereo amplifier, you'll hear the whole thing move left and right as you move the balance.

Imagine how exciting stereo hi-fi must have been to people used to listening in mono, back in the days when it was first released!

All my amplifiers can switch between mono and stereo output. If I listen to a stereo track in mono, my balance control has the same effect as it would, had the image been recorded in mono: it moves everything left or everything right.

Terms:
Panning & balance appear to do the same thing at face value but panning is usually applied to single instrument/source inputs to decide their place in the stereo image, while a balance control let's us 'look around' WITHIN the summed output of all those (differently panned) track/inputs.

Imagine the balance control on your playback gear as a window you can shift around, to view parts of the image.

When you move a balance control over a stereo image, you're able to view different parts of the image.

When you move the balance control over a mono image, you're moving the whole image at once. In a sense, it becomes more a panning action than a balancing one, because there isn't really anything seperable in there to balance.

Remember that panning controls are for moving individual parts around when recording that image.

Also remember, there are many variants of 'stereo', depending mainly on how a track is recorded and mastered.

Dr. V

 

[Farview]

But lets say if i now were to make a new channel strip and insert a new synth, only this time making it mono. Now the volume bar will appear as one, and not split like in stereo. And now lets say i'll pan it to left as i did with the stereo track. What happens? The sound gets stronger on the left speaker, and weaker on the right speaker. My question is of course: This is exactly what happens in stereo too, so what the heck is the difference?

You are getting confused between a stereo instrument (or sound) and a stereo mix.

A stereo instrument normally has differences for one side to the other. A piano patch, for example, will have the higher notes off to one side and the lower notes off to the other. It has it's own stereo image. You have the option of just placing that stereo image in your mix or panning it around to place it in the mix.

In my situation, I record everything as mono tracks and pan them to create a stereo mix.

Think of it this way: If you record yourself singing 20 times, you will end up with 20 mono tracks. If you pan them around the stereo field, you will create a stereo mix.