Thoughts on the 3 to 1 miking rule.

[rick-slo]

Originally Posted by Trevor B.

Thanks for the link. Just to be clear, I did not think of the 3:1 rule as applying to the measurement of distance between mikes and source but rather the distance in a lateral sense between mikes compared to their distance from the source. If we conclude that the "independent recording' assertion is correct then my insurmountable obstacle or "wall" as it's more often referred to ceases to be an issue.

The lateral distance can be anywhere from zero (coincident (like X/Y)) to where you start to hear a hole in the middle of the soundstage, i.e. there is a lot of leeway. With close mic'ing six inches out and a three foot mike separation might work, as could two feet out and the same three foot mike separation.

[Trevor B.]

Originally Posted by Doug Young

The biggest problem with following recording articles, is that recording solo guitar is so rare, in the grand scheme of things, that it's a pretty specialized process that most people aren't addressing it in these articles.

Sums up perfectly why I asked for input here.

Originally Posted by rick-slo

The lateral distance can be anywhere from zero (coincident (like X/Y)) to where you start to hear a hole in the middle of the soundstage, i.e. there is a lot of leeway. With close mic'ing six inches out and a three foot mike separation might work, as could two feet out and the same three foot mike separation.

Makes sense. Let the experimentation resume!

[Steev]

Originally Posted by Trevor B.

Your suggestions basically mirror what I've been doing as does your latest recording set-up. However; my ultimate goal is to record a CD project here in my little home studio so the miking set -up I settle on will have to sum to mono. M/S will get the job done but so far my attempts at it have been mixed at best.

If you use an omni instead of a cardiod with your figure 8 for M/S it should sum to mono just fine.

[Doug Young]

Originally Posted by Trevor B.

Your suggestions basically mirror what I've been doing as does your latest recording set-up. However; my ultimate goal is to record a CD project here in my little home studio so the miking set -up I settle on will have to sum to mono. M/S will get the job done but so far my attempts at it have been mixed at best.

Trevor, why do you need to sum to mono for a CD? Probably worth a separate thread on ms, too, it should work great. I do a lot of MS, as do others here, so Im sure we can get that working for you, if thats what you want.

[Bob Womack]

Summing to mono is a mindless downstream inevitability that is out of your control and doesn't care a whit about your preferences. It will happen, be it from an inept digitizing employee at a streaming service, an inexperienced local DJ, a poorly-adjusted computer sound card, a person who inserts the headphone jack halfway, a shorted input cable, the playback from a mono iPhone speaker, a broadcast received on an older mono TV, or an unaware user who hits the mono button on a receiver. It is true that it happens less these days, but it still... just happens.

All that is left to you is to decide whether or not you want to be represented by a fundamentally flawed product when the time comes.

Bob

[Doug Young]

You're more experienced with this stuff than most of us here, Bob. But I'd hazard a guess that the issues you point out are more critical for band mixes than solo acoustic instrumental guitar (which is what I think Trevor is doing), would you agree? In the worst case, with a band, you might lose something entirely, like a vocal, if it isn't done correctly for mono.

But for solo guitar, using spaced pairs, which isn't strictly 100% mono-compatible, is extremely common. I wouldn't suggest anyone try to be particularly mono *incompatible*, but whether a spaced pairs recording, done properly for solo guitar, would sound less than perfect in corner cases, like being played over an old TV, wouldn't stop me from recording a CD.

The issue of end users doing stuff to your well-recorded tracks is interesting, I wonder how you deal with it?. Listening in mono almost seems like the least of the worries these days. I wouldn't be surprised if these days, there are more people who have their home stereos mis-wired to be out phase than those who listen in mono, for example.

I do like MS, as it's not only mono-compatible (which is not to say the sound doesn't change when switched to mono - everything narrows and you lose the "air" of the stereo field), but it also creates a nice focus, probably due to the phase coherency.

Again, Trevor, I'd suggest posting some examples of what you're doing with MS, and I'm sure lots of people here can help. It's pretty simple once you get it, and it will address any mono-compatibility concerns.

[rick-slo]

Originally Posted by Bob Womack

Summing to mono is a mindless downstream inevitability that is out of your control and doesn't care a whit about your preferences. It will happen, be it from an inept digitizing employee at a streaming service, an inexperienced local DJ, a poorly-adjusted computer sound card, a person who inserts the headphone jack halfway, a shorted input cable, the playback from a mono iPhone speaker, a broadcast received on an older mono TV, or an unaware user who hits the mono button on a receiver. It is true that it happens less these days, but it still... just happens.

All that is left to you is to decide whether or not you want to be represented by a fundamentally flawed product when the time comes.

Bob

The few unattentive mono listeners, either from ineptitude or use of antiquated playback systems, deserve what they get.

More to the point, people doing serious, or at least semi serious, listening to music recorded in stereo will be doing there listening in stereo. If there was no sacrificing of the advantages of the stereo sound trying to be mono compatible (a fully mono compatible stereo recording is in effect mono from the get go (other than MS recording I suppose, but that narrows the stereo sound choices considerably)) then it would not be an issue. Even a mono recording with stereo reverb added post recording gets wacked listened to in mono. Tradeoffs occur in most every choice one makes in the world.

[Bob Womack]

Originally Posted by Doug Young

You're more experienced with this stuff than most of us here, Bob. But I'd hazard a guess that the issues you point out are more critical for band mixes than solo acoustic instrumental guitar (which is what I think Trevor is doing), would you agree? In the worst case, with a band, you might lose something entirely, like a vocal, if it isn't done correctly for mono.

But for solo guitar, using spaced pairs, which isn't strictly 100% mono-compatible, is extremely common. I wouldn't suggest anyone try to be particularly mono *incompatible*, but whether a spaced pairs recording, done properly for solo guitar, would sound less than perfect in corner cases, like being played over an old TV, wouldn't stop me from recording a CD.

You ask a lot of good questions in this post. To start off, no, I wouldn't let a fear of not catching something stop me from recording a CD. These days few can afford a good studio and so many good tools are out there that musicians can use. It makes good sense to record your own. The effect of an out-of-phase spaced pair when summed is comb-filtering of the sort you hear in a flanger, but stationary, not sweeping. You just want to sweeten the effect of being summed by finding a sweet spot. Once you get there, measure your setup for distances and angle and store the info for next time.

The issue of end users doing stuff to your well-recorded tracks is interesting, I wonder how you deal with it?. Listening in mono almost seems like the least of the worries these days.

There's a summing button on the monitor section of the console in my studio. I just make a habit of whacking it now and again to verify that there aren't bad effects happening. The other day I was recording an acoustic guitar in a fast-paced session. I've got a couple of arrays I use where I've measured distances and angles once I've come up with an array that works. I pull out my ruler and protractor and set 'em up with that and then do two things: I check before recording with the mono monitor button and I watch my DK phase meter with its "jellyfish" phase display. We've got it across the mix bus and use destructive solo to audition tracks. You can get plugins that show the same info - An absolutely mono signal yields an absolutely vertical line, an absolutely out-of phase signal yields a horizontal line, the jellyfish blob tends horizontal when you are more out-of-phase or non-coherent and vertical when you are more in-phase. Stereo pan shows as lines tilting one way or another. It also has surround modes for when I mix in surround.

Other than that, I shop the mixes through four different monitor systems (UREI 813Cs and 811Cs, Genlec 1032as, a JBL LSR array, a Bag End array, and Auratones) and a really nice Harmon Kardon car system. I make the stuff as mono-compatible as possible and then the bad stuff just happens.

At the beginning of 5.1 surround mixing everyone had to learn the hard lesson that users will find a way, often the most embarrassing way, to mess with things. The first big one was discovering that band mixes with only the vocals in the center speaker allowed the user to disconnect the other speakers and hang the vocalist out to dry as a solo. Woop. Got over that one quickly when the vocalists screamed.

I wouldn't be surprised if these days, there are more people who have their home stereos mis-wired to be out phase than those who listen in mono, for example.

Of course, with subwoofers you will probably still have bass but where did all the low-mids gooooooo...

Bob

[Trevor B.]

Originally Posted by Doug Young

Trevor, why do you need to sum to mono for a CD?

For the hearing impaired.

Originally Posted by rick-slo

The few unattentive mono listeners, either from ineptitude or use of antiquated playback systems, deserve what they get.

Gotta love this response!!!

Thanks to everyone who has responded to my initial question and made this another fascinating and informative thread. Not to sound patronizing, but this section of the AGF has been and continues to be a crucial resource for me.
Over the next few weeks it is my intention to post some clips of my home recording efforts and I'll be looking for as much input as you're all willing to share.

Trevor

[Doug Young]

Originally Posted by Trevor B.

For the hearing impaired.

Interesting. Sounds like you have some specific target audience for your CD? I'm not sure any micing technique really addresses a 1 ear'd listener, other than actual mono. MS would be reasonable, if the listener is actually summing to mono, tho you'd want to be sure the mid mic actually sounds good by itself. I've never recorded a mono recording I actually liked.

[Trevor B.]

Originally Posted by Doug Young

Interesting. Sounds like you have some specific target audience for your CD? I'm not sure any micing technique really addresses a 1 ear'd listener, other than actual mono. MS would be reasonable, if the listener is actually summing to mono, tho you'd want to be sure the mid mic actually sounds good by itself. I've never recorded a mono recording I actually liked.

I have a couple of options for recording M/S (i.e. one of my Gefells for the mid and a Sennheiser MKH 800 P48 that can be set to Figure of 8 for the sides). It's also my understanding that if a spaced pair is not panned hard left and right it will sum to mono, yes? The other question that is pertinent here is this: if I record a stereo track and hit the mono button on the output channel I'd hear if there are phase issues going on, correct?

[MikeBmusic]

Other places where mono playback is important - sound systems at clubs and bars (including jukeboxes); most PA systems - although many are stereo compatible (mixers and separate power amps for L + R), its common practice to run them in mono so that the soundscape doesn't vary depending on where you are in the place. This would also include if you use an MP3 player for backing tracks or for break music through your Loudbox, too.

[Doug Young]

Originally Posted by MikeBmusic

Other places where mono playback is important - sound systems at clubs and bars (including jukeboxes); most PA systems - although many are stereo compatible (mixers and separate power amps for L + R), its common practice to run them in mono so that the soundscape doesn't vary depending on where you are in the place. This would also include if you use an MP3 player for backing tracks or for break music through your Loudbox, too.

This probably comes down to style of music differences. Those of us saying we aren't overly concerned about mono applications record solo instrument fingerstyle guitar. I don't expect to ever hear my music in a bar, jukebox, or used as backing tracks. :-) Just not my target audience. The audience for solo guitar expects stereo, since that's how virtually all modern fingerstyle recordings are done, and spaced pairs, with it's inherently weak phase correlation is arguably the most common technique used in solo fingerstyle recordings. We had a thread recently arguing that single mic, mono recordings were the one and only true way to record, but I doubt it will catch on :-)

Bob, thanks for the additional details. I frequently check the mono button, use phase correlation meters, among others, when setting up mics, and keep a ruler handy. I have a monitor placed right in front of my playing positions with a pile of meters that I can monitor, even keeping an eye on them as I record to make sure I don't shift in my seat or whatever. But when I used spaced pairs, that of course still ends up with some comb filtering when mono'd. I just can't imagine it mattering, as long as I'm reasonably phase-aligned, in any environment in which my music would be played. It sounds like Trevor is going for some specific listeners who hear differently, so that's a different story than most of our situations.

[Doug Young]

Originally Posted by Trevor B.

I have a couple of options for recording M/S (i.e. one of my Gefells for the mid and a Sennheiser MKH 800 P48 that can be set to Figure of 8 for the sides). It's also my understanding that if a spaced pair is not panned hard left and right it will sum to mono, yes? The other question that is pertinent here is this: if I record a stereo track and hit the mono button on the output channel I'd hear if there are phase issues going on, correct?

If you record spaced pairs and pan them inwards, you will start mixing the two signals. If both are panned to the center you will have mono. All panning inward does in a DAW is start mixing in part of one channel into the other. You will hear the effect of summing to mono, which in the case of spaced pairs will be some phase cancellation, or comb-filtering. There will be big cuts at certain frequencies, which varies depending on where your mics are placed.

It may or may not sound "bad", you'll have to decide. You'll most certainly hear a change in tone, since it's not possible to have spaced pairs on a guitar be perfectly in phase - the phase differences are part of what created the stereo cue's in spaced pair mic setups. You can reduce or mostly eliminate this by using other mic placements, like XY, ORTF, NOS, or MS. But with spaced pairs, the phase differences are a feature, they're why you would choose to use spaced pairs, because it creates a spacious sound, using phase differences to enhance the stereo effect.

MS summed to mono also works based on phase cancellation, but due to the way MS works, what happens is the right and left "sides" that come from the side figure 8 mic completely cancel, with no comb filtering. So you're left with only the signal from the mid mic, as if you recorded to mono. So if you do that, and expect to be played back in mono, you'll want to pay special attention to making sure that mono mid mic sounds good all by itself.

[Trevor B.]

Originally Posted by Doug Young

It sounds like Trevor is going for some specific listeners who hear differently, so that's a different story than most of our situations.

Suffice to say I'm trying to cover the bases by aiming to make recordings with a wide stereo image for those with the hearing capacity and available sound systems to enjoy it while at the same time taking into account that many "seniors" no longer have either. My repertoire tends towards classical pieces and traditional instrumental folk song arrangements. No surprise then that my audience tends to have even whiter hair than I do.