Edit: For clarification sake...i should mention the rule states the distance should be ATLEAST 3X the distance. Keyword being atleast. I gloss over that a couple times in the video. Remember folks, it's all about SIGNAL amplitude. Well...not all about. These things are really complex actually. Regardless I stand by the use of the 3:1 rule on a single source. If you disagree with my reasoning please yell at me below. Please and thank you. Cheers!
if you place the second mic on a moveable arm you can use the phase cancellation to your advantage. Get the guitarist to play, get someone else to move the mic while you monitor it and pick the phased tone that you like :)
I describe it to newbies like the wave is where the speaker cone is, so telling the cone to pull in and push out at the same time means it just sits still so no sound.
Excellent video. Since we all work with sound, something only ever entirely audible and not visual, its also good to encourage engineers to simply use their ears first and foremost, before really every getting caught up in the semantics of these scenarios. As a rule of thumb yes keep phasing in mind, but more or less the fact that it's inevitable rather than waste the energy and time fighting it.
Yes, this is a gigantic reason why I tell people to put the damn DAW down. It's always visual based. Our brains are very intricate things and when we process information, our eyes can persuade us to hear something other than what we are actually hearing. This goes for more than just music of course. Speech is a good example of non-music related sounds that our eyes play a big role in. By removing our eyes from the equation when tracking/mixing we ensure that the end result will sound the same to the end user. The only visual aid I use when recording music is a VU meter. And that is simply just to see if I am peaking most of the time. Theoretically I could probably get away with just a peak LED meter when tracking and mixing. That would be a fun exercise.
Love the information in this video, even though I knew some stuff about phase cancellation before, this helped give a further understanding of it. I like to think of this with two guitar pickups being out of phase, often times electrically giving an inverted signal due to wiring or the magnet inside of the pickup being flipped. The electrical waves cancel eachother, but not perfectly due to multiple reasons, for example, the two pickups being wound differently, and also because of the natural placement of the pickup is going to give two different tonal signals, (ex. Pickup "A" is placed towards the bridge, giving more treble/twang in the signal, and Pickup "B" being closer to the neck of the guitar giving more bass in the signal.)
More great content from my favorite DIY recording channel. I was unaware of the 3:1 rule, but I reckon the 3:1 rule comes not from level reduction (after all, you could pot up the far mic to the level of the near mic), but because the far mic gets more sound from multiple paths in the room and therefore cancellation at any given frequency is minimal. Anyway I'm going to try this this weekend on my drum kit, 1 mic in the middle of the kit just over the bass drum, and one over my shoulder.
What you're saying is true. The farther mic is acting as a room mic so the signal is "colored" so to speak and doesn't match the first mics signal. Also correct that raising the gain of the second mic WILL cause more phasing.
Hi Mario. I get the "decibel difference" interpretation, but let's figure out a real world scenario: let's say that you set up two identical mics, one 2" from the speaker, one 2' away. Let's say that you hook up both mics to two identical preamps, set with the same amount of gain. What you get is that the first mic is much louder than the second mic because it's much closer. If you mantain these levels ratio you would probably get away with the comb filtering effect because if the amplitude difference between two signals is >10dB the phase cancellation is heavily reduced. But if you want more room sound and you bring up the far mic you'll get a lot of cancellation. But comb filtering happens only with very short delay times (
Mario this is hilarious. The 3 to 1 rule is something I learned in school and it's kind of amazing to me that you have people saying you're an idiot for following it. If you wanted to simplify your explanation even further, the 3 to rule is just a basic way to make sure that your two microphone capsules are firing the same way at the same time. In it's simplest form, a microphone creates an electrical signal that is either positive or negative depending on whether or not the diaphragm is being pushed or pulled. If they are going in opposite directions when you record, you get phase cancelation in the way you described. That's all the rule is there for. If you want a real world example of it, the best one I can think of is a snare mic'd with a top and bottom mic. the capsules are usually facing each other, and as a consequence the are firing in opposite directions. If you leave them as they are, your snare sounds thin with no bottom end. If you flip the phase on the bottom mic, your low end comes back. The 3 to 1 rule basically does the same thing, but it does it in the room at the time of recording. EDIT: I forgot to mention that if you want to see a prime example of the 3 to 1 rule in action, take a look at ANY decca tree microphone bar. They have exact measurements on them to minimize phase cancelation, and generally they are designed around the 3 to 1 rule. Keep up the good work. 😎
Anyone who has ever recorded drums with stereo overheads knows this is a constant struggle. Especially if you like more mono(ish) panning. Personally, that's part of the reason why I like the Glyn John drum technique. . having each overhead mic on a different plain/axis relative to each and far away from each other other really seems to eliminate a lot of that, and it just sounds rad.
Something important that the Glyn John Technique specifies as well is equal distance from the two "overhead" mics from the snare. This is for the exact reasons I mention in the video. Since the snare is the most important part of the drum kit, this ensures the two microphones are hearing the snare soundwaves at exactly the same moment in time, thus eliminating phasing issues for that part of the kit. Of course this means the toms and cymbals might be slightly out of phase but this is just a compromise as always with drum micing.@@ToneSherpa
Thanks Scott, didn't know you went to audio school. Good point you bring up about the decca tree design. I don't know much about it I am going to have to look up the math/science behind their design, thanks. You're totally right about the polarity flip for the two mic snare setup this is very important. Unfortunately my mixing board doesn't have a phase switch anywhere!!! So I have no easy way to do this. Very frustrating. This is why I always make sure my mics sound good before they ever get to my mixing board.
@@Mario_DiSantoSome old mics are just wired backwards from factory I've heard. Some old soviet mics and such. Maybe you could use one of those as a snare bottom? Maybe some basic soldering skills on a regular mic and you could modify it to reverse polarity?
Polar pattern of the mics would also come into play if you are trying to avoid phase cancellation based on DB (attenuation) vs phase relation with two sources.
You are a very good educator and I am getting a lot out of these videos. I am making better recordings. Thank you very much. Liked, subscribed, belled and shared.
The 3:1 "rule" just isn't a rule, the problem is that people teach it as a rule and say if you follow it you are going to be "ok" . The entire rule breaks apart as you shorten the distances and get closer to the source, like close micing a guitar cab. if the initial distance is 1cm and the second mic is at 3cm, the 3:1 rule does nothing at all to help keep your phase coherent. I think the 3:1 "rule" was developed when close micing was not the usual practice and farther mics were. At greater distances the higher wavelengths are too close to fold back on each other in a reasonable time domain to cause severe combfiltering and instead your ears, or rather your brain thinks of the more distant mic as actual ambience. when the 2 mics are too close to the source, there is no ratio that will fix that problem because you are mathematically closer to the range of the high end, where you perceive comb filtering in longer wavelengths so if the distances become farther, it is less problematic. If you are recording a line of trumpets spaced 3' apart, anything that is going to fold isn't going to be perceived as comb filtering for the most part . Now, where you are DEAD RIGHT is "who cares". If you put up 2 mics and it sounds good... it IS right. I say ignore the ratio rule because it is misleading and just move your second mic till you like it. Love your videos. Don't be mad, this is and industry built on people saying you are doing it wrong and people doing it anyway.
You make two good points here. One is that this rule is more applicable to mics that aren't close mics. The 1cm and 3cm example is a great example why that is. The distance + amplitude differences is simply to small for there NOT to be an issue. The second point is that "you should move the two mics until they sound good". This is essentially what I do anyway when I "apply" the 3:1 rule. As I mentioned in the video I'm not actually measuring anything when I do this in the studio. I am more looking at the two mics and mentally saying "okay this is a good starting point because the two mics are reasonably set apart from each other". And then I adjust from there. 6/10 times it sounds good enough for my tastes and I leave their positions as is. This is all coming full circle now because I'm starting to see WHY so many people are against the 3:1 rule. It gives people false security. I by my own omission don't follow the 3:1 rule per the definition. I'm really just making a visual check to make sure the mics aren't too close and then adjusting from there. Regardless I think the principle in which the 3:1 rule works is still paramount to understand and I stand by that it only has to do with signal amplitude and not actual distances. I bet I could do some tests to actually test this theory. Anyway I appreciate the actual response! Cheers mate
@@Mario_DiSanto No prob. I think the thing that people get confused about 3:1 the most is that the actual distance isn't the point, its achieving a discrepancy in amplitude between the mics so your brain can process one as ambience and the other as a direct source. I think the original spec was something like trying to achieve a 10dbB drop in the farther mic, which given the same gain and and using the same mic, 3x the distance naturally achieves. You will see in a lot of old tech writing that it doesn't say 3:1 or 3 times the distance, but "At Least 3 times the distance " and similar descriptions. It's never really been about phase alignment, but psychoacoustics. Keep up the great work. Your videos are a bunch of fun.
As fun as is is to make good music, it is really important to understand the physics, science and math behind the art. Recording has its own challenges which are already answered, hence the video.. As an electronic producer, I can say most of our issues are in the sub freqs. But the science is still the same. And very very helpful to know and practice.. be good producers guys, great artist.
I didn't find any issue with your comments on phase from the previous video. I've recorded a lot of drums and always check phase relationships between the mics on the kit, but I use my ears rather than zooming in on the wave forms in my daw. The snare can be a good indicator to hear phase relationships that are working well together without excess cancellation. If the snare sounds thin, I'll flip the phase switch of a specific channel(s) and that almost always fixes it. If not, I'll go right to the source and adjust the mic position. At this point, I know generally what mics I like on the kit and where to put them in accordance with the sound of the room, so I usually don't have to do a ton of adjustments. I also will record with extra mics in positions that won't always get used in the final mix, but they give me more options. That freedom is the beauty of recording into a daw. I do have a 4 track tape recorder as well though, which I mostly use for character. I don't record amps with multiple mics very often, but I have heard of the 3 to 1 rule. You've inspired me to give that 2 mic setup a try soon!
The two mic on a guitar cab is a fun setup. I don't always use it because there is more testing involved to get a good sound (for the reasons I talk about in this video). But man when you get everything set right is sounds AWESOME. I really only use it on tracks where I want the guitar to be the focal point of the track. Cheers
If you put one mic in front of your open back amp and another behind your open back amp, the two signals will have big phase cancellation. The same as blending a top and bottom miked snare.
I've never had any issues, I just put the back mic on a slightly different axis and further away. badda bing badda boom. no phase issues. there's no getting around the snare issue though. flipping the phase is the only way... although, sometimes the thinning of the snare tone can be desirable, depending on the song.
There's a Steve Albini video where he talks about what he calls 'time aligning' sources and he has a digital delay he can time down to like 10s of mili seconds and he literally uses an oscilloscope to align two microphones to make his point. It's actually a pretty good video. I guess if you're recording nirvana and have massive budgets and Studers and stuff you've got the time to literally measure the phase alignment at your favorite frequency.
Yes good point. I have seen that video years ago. Like you said if you have big money and time to spend doing that stuff, by all means go ahead and get technical. But for the average home recordist working in a acoustical mess of a recording room you have much bigger problems to worry about and probably don't have the technical knowledge to use an oscilloscope. Interestingly enough, I've never been a big fan of the sound Steve Albini gets on the records he cuts. This is no offense to him in anyway he obviously has more skill in his toenail than I do entirely. I think I just tend to love the less polished types of recordings. He gets a very "natural" sound is the best way I can describe. I dig the over compressed, blown to bits, garage rock type of vibe. Just a matter of taste of course.
@@Mario_DiSanto totally agree with you about hos sound, not how I would want stuff to sound. But I do love his attitude toward music and a being a big tape nut always warms my heart a bit.
At 21:40 you can see the napkin drawn by Nigel Tufnell, confusing feet for inches. Love it. thanks for sharing your knowledge, it's really helpful. Seen your vids before, have decided to subscribe. Your enthusiasm is winning. It's probably me who's confused, heh.
Yeah, phase cancelation won't be significant if the mic recording levels are equal using a 3:1 distance from source ratio because cancelation increases exponentially below a ~6dB difference. Chances are you are not increasing the 2nd mic level to match the first, and the mic distance you like to use of 3~4' ends up being in the proximity boost range of the close mic anyway, further reducing mutual cancelation. Not sure I'd want the example you give here of 2.2kHz cancelation in general, as long as the mic signal levels aren't set close to equal. One thing I might do is to run pink noise through speaker and use a cell phone FA app to mark where in your room the least bass cancelations are to mic from. Maybe even denote the freqs on pieces of tape placed at the spots.
Ya know that is a good point about increasing mic levels. Technically (if we are to look at this in a simplistic model sense), if I were to increase the gain on my second microphone to a certain amount I would be seeing TOTAL attenuation of the signal at certain frequencies. And when I am "blending" the two mics on my guitar amp this is a factor to consider. Of course I don't take the time to do any math, I just simply listen with my ears and make a decision on whether it sounds good or not. Thanks
Another exemple why Rule #1 is : There’s no rule. It’s more something to be aware of, to take in consideration. Even more with drums, mic directions, and polar patterns,… and yes it’s way more than just the total cancellation of that particular freq… BTW as you know , Top engineers often put different mics side by side on guitar cabs and blend them.
Let me make this simple. Sound amplitude falls off as the SQUARE of the distance. That's called the "Inverse Square Law". What it means in simple terms is that sound amplitude falls off REALLY quickly the farther away you (or the microphone) are. Put even more simply, the second mic. quickly becomes a non-issue. Bill P.
Exactly Bill! I probably should have mentioned the specifics in the video because this is a big one. A few things fall off in amplitude as a square of the distance: sound, gravity, magnetics, radiation, light, etc. etc. It's been a while since I opened up one of my engineering textbooks but I believe this is directly due to the increase in area/volume as you move away from a point source in three dimensional space. Cheers mate
I explained this to singer I had mic'd (well, just placed a mic in front of her), and when she didn't understand because she sang too close and then backed away too much on louder notes, I said: Say your ear is 1 inch from my mouth and I yell, versus if I take 3 feet back and yell, you'll notice the loudness difference way more than Scenario B: I'm 100 feet across the street and yell at you, then yell the same strength but 103 feet away, you'll have trouble telling the difference, well that's how the inverse square law works :)
@@mrkite89 the original source signal will be low but there will be reverberation from the room in that mic. Usually a 'room mic' is lower in volume as well.
I was taught to do this equilateral thing... maybe 2:1 or whatever.. both mics at the same distance from the source, like how you setup speakers.. but now I just might have to try this and A-B it; trust your ears, f* yes
I'd be more worried about phase issues if you were using two cardioid, or hyper cardioids. The way you miked the cab with one omni, and one cardioid? Minimizes phase issues. The omni mic's pickup and what it's "hearing" is SO radically different from the cardioid, you're not going to get a ton of cancellation or comb filtering. I do this with a 635, or and ev do56, or a tube mic in omni all the time. BTW, we used to have almost the exact rig, but it was an M520 console with an MS-16 recorder. Way, way back in the early 90's. My brother now has the M520 in his outbuilding / garage studio. Brings back memories. Good times.
Very true. I really should have touched upon this. My second omni mic is essentially working as a room mic in this two mic setup. Well kinda...2 feet away from a source isn't really a room mic, but same concept. Cheers
Yeah, if it's in the room, and in omni, you're right. It's a room mic :,) Nice original video, and I'm glad to see someone your age with some excitement about tape and consoles etc. Going to subscribe i think! Thanks for putting in the effort. People don't realize how much work it is doing these videos.@@Mario_DiSanto
But there absolutely is a Band-Aid in the case where there are two microphones recording the same source, which is manually time-aligning your tracks. Assuming both mics are in the same atmosphere and are subject to the same speed of sound lol. Obviously a great solution for multiple source multiple mic setups like drums.
This is true. I might do a video on this idea because I have had a few people comment this. Probably a lot easier to do in a DAW. I gotta set it up with my delay and oscilloscope. Could be interesting.
If the 3:1 rule is based completely off of decibel levels, why not just attenuate the volume of the 2nd microphone? Its hard to believe that the source you referenced would not explicitly state that the rule is based entirely on decibel level, if that is indeed the case. Decibel level certainly matters, but there are other factors in play. The change is distance from the source is also going to change the uniformity of the wave forms due to the proximity effect of the microphones and high end roll off. So, when changing distance, you change both the decibel level and the frequency profile. BOTH matter. Even so, good video. Got me thinking and I could be wrong.
No you are 100% right. Although instead of frequency profile I would say it has to do with the room sound more. Farther away from the source you are, the more room sound you will have, therefore the signal will be sufficiently different from the first close mic. When I say it has more to do with decibel levels I meant in an ideal world that I modelled on my whiteboard. Simple sine waves that aren't influenced by outside factors such as reverberation due to surroundings or other factors (ie. Proximity effect, room sound, diffraction, etc). I hope you can agree! Cheers
Yeah, the room noise would definitely be a factor too. I take your point on the sine waves and I think we agree in general. I'm wondering if the distance would also mean that the fundamentals are more likely to cancel while the higher harmonics are more likely to be spared when combined.
@@dean_the_mystic in the perfect modelled world I just described I would argue no. But in the real world I would say you are correct about the harmonics blending better. Just a gut feeling though.
This was a great video! I think it's important that you highlighted that the 3:1 rule is a rule of thumb, not a fascist regime. By the way, I'm swedish, and 3 feet is roughly 1 meter in the metric system. 1 meter is easier to remember. ;) Would you please make a video on recording acoustic guitar and wooden acoustic instruments in general? I would love to hear your opinions on the topic.
Two mics on a single source is always a bad idea. You are creating a filter no mater what you do. The best you can hope for is an allpass, but that would require 3 or more mics.
i have not watched the whole video, because tldw) 3:1 rule applies to recording different sources (more than one) with different microphones, not one source (your amp) with different microphones.
Boi...I literally talk about this throughout the whole of the vidya ya bum! The principle in which the 3:1 rule works is on 'signal amplitude'. This works regardless of a single source or multiple source. The same physics/mathematics will apply. Of course in the real world, life isn't exact science, but the principle of attenuation of signals remains true.
@@Mario_DiSantoYou have to start by stating what the 3:1 Rule is, set the context. Then you expand on the established topic. Something about phase? Okay... So there is some rule.... What is the rule? You immediately jump into phase cancellation without stating the contents of this "3:1 Rule".
Are you kidding! All I ever hear anyone say is the Imperial system sucks and the Metric system is superior! Especially in the engineering world. I like to use both for different reasons.
@@Mario_DiSanto of course i think metric ist better, not only i grew Up with it. Im kinda in the engeneering world too. But in the other Hand, being fluent with imperial ist a good Training for your brain. Maybe your faster with calculations, me will be calcu-late... 😎 And bullying americans for their systems is not Superior.
9:12 "ya metric 'nerds' " -> 79% (4 out of 5) of the world uses the metric system (Liberia, Canada (which uses both) and US. only making 21% of the 8 billion world population). Still funny though, nice video :)
i just don't get why someone who advocates for proper pre-digital studio methods and is prepared to fork out for a Space Echo won't just get a halfway decent analogue delay and use it to buffer the close mic so that the signals are aligned. it just makes no sense. the 3:1 rule is what you do if you literally only have two mics and tape-measure. if you're in a studio, if you're tracking to a multi-track console, if you're gonna spend money on vintage fx units - it just seems really incongruous that you'd use such a compromised approach. (edit - full disclosure - reason i have a bug up my ass about this is because when i first started recording as a kid, i listened to some know it all guy who was older and cooler than me tell me to use a distant mic as well as my close-mic on my amp, (tbc - this butthole didn't even mention the 3:1 rule, or anything to do with phase issues at all so i'm not saying you're as bad as him!) and for like, about a year i tried this approach into my little four-track and just couldn't figure out why no matter what i did, everything just sounded weaker and lamer than when i just used one mic... so, yeah - i have 'bad mic placement advice' trauma issues that i guess i'm still working through. 😄)
Before I go on, I should mention that I NEVER use two microphones on a single source. Two microphones on any source is never a good idea, mostly because it usually isn't necessary and just brings up potential problems with phasing. That guitar recording method from the last video is the ONLY instance where I break the "less is more" rule. So why do I break this rule for that guitar recording method? Simple answer...I like the way it sounds. No other reason. It's not because I get better frequency response, or that I am able to control the dynamics better, or whatever specific reason. The simple and sole reason is because..."I like the way it sounds". So I use this phrase to answer your question of "why not go through a delay to make sure you are minimizing phasing issues"; "I like the way it sounds". Why change something that I like? Music is incredibly subjective where rules are always meant to be broken. Should I change the way something sounds because scientifically it's not the 'correct' way to record it? I certainly don't think so. If I like it, I like it. Simple. I do have an analog delay that I could delay the signal as you are describing. Perhaps I will do a video on doing just that to demonstrate the "proper" way of doing this (but more importantly to make you happy lol). But my point still stands that I shouldn't necessarily do something just because I'm 'supposed' to. I am a home recordist and I record music for fun. I am not concerned with clients worrying if I am recording something the "right way". No one is paying me to be a professional. I don't have to worry about sending my tracking session to another mixing engineer for them to work with. My only concern is if I like the end product. Ya see what I am getting at here? In my videos I never try to be the guy that tells people the "best way" to record anything. Which is why I titled the video "My favorite way..." and not "The best way". I just hope to spur some creativity. If I occasionally give some 'out-of-the-box' advice, so be it! It's not like I am putting someone in physical danger. Worse comes to worst they try my method and think it sounds like doo-doo. And fair enough! I have tried people's recording advice before and hated it. It's the experimentation that is fun for me. But regardless, I am glad for the pushback because it made me think deep about the 3:1 rule, and that is where I come to my own conclusion that it solely (or I guess mostly) has to do with amplitude differences and not distances that the 3:1 rule relies on. Understanding the physics is important even when you aren't following the "best way" so you at least understand what you are doing "wrong". Cheers
Phase cancel culture is vicious
No it’s not. Shut up. Can we ban this guy please ☝️ hello?! Can we?!
Edit: For clarification sake...i should mention the rule states the distance should be ATLEAST 3X the distance. Keyword being atleast. I gloss over that a couple times in the video.
Remember folks, it's all about SIGNAL amplitude. Well...not all about. These things are really complex actually. Regardless I stand by the use of the 3:1 rule on a single source. If you disagree with my reasoning please yell at me below. Please and thank you.
Cheers!
if you place the second mic on a moveable arm you can use the phase cancellation to your advantage. Get the guitarist to play, get someone else to move the mic while you monitor it and pick the phased tone that you like :)
I describe it to newbies like the wave is where the speaker cone is, so telling the cone to pull in and push out at the same time means it just sits still so no sound.
Excellent video. Since we all work with sound, something only ever entirely audible and not visual, its also good to encourage engineers to simply use their ears first and foremost, before really every getting caught up in the semantics of these scenarios. As a rule of thumb yes keep phasing in mind, but more or less the fact that it's inevitable rather than waste the energy and time fighting it.
Yes, this is a gigantic reason why I tell people to put the damn DAW down. It's always visual based. Our brains are very intricate things and when we process information, our eyes can persuade us to hear something other than what we are actually hearing. This goes for more than just music of course. Speech is a good example of non-music related sounds that our eyes play a big role in.
By removing our eyes from the equation when tracking/mixing we ensure that the end result will sound the same to the end user.
The only visual aid I use when recording music is a VU meter. And that is simply just to see if I am peaking most of the time. Theoretically I could probably get away with just a peak LED meter when tracking and mixing. That would be a fun exercise.
love this, thank you for every info you share
You're welcome man. Thanks for commenting.
Love the information in this video, even though I knew some stuff about phase cancellation before, this helped give a further understanding of it. I like to think of this with two guitar pickups being out of phase, often times electrically giving an inverted signal due to wiring or the magnet inside of the pickup being flipped. The electrical waves cancel eachother, but not perfectly due to multiple reasons, for example, the two pickups being wound differently, and also because of the natural placement of the pickup is going to give two different tonal signals, (ex. Pickup "A" is placed towards the bridge, giving more treble/twang in the signal, and Pickup "B" being closer to the neck of the guitar giving more bass in the signal.)
You're a good dude. Thank you man I appreciate what you do
More great content from my favorite DIY recording channel. I was unaware of the 3:1 rule, but I reckon the 3:1 rule comes not from level reduction (after all, you could pot up the far mic to the level of the near mic), but because the far mic gets more sound from multiple paths in the room and therefore cancellation at any given frequency is minimal. Anyway I'm going to try this this weekend on my drum kit, 1 mic in the middle of the kit just over the bass drum, and one over my shoulder.
What you're saying is true. The farther mic is acting as a room mic so the signal is "colored" so to speak and doesn't match the first mics signal.
Also correct that raising the gain of the second mic WILL cause more phasing.
Hi Mario. I get the "decibel difference" interpretation, but let's figure out a real world scenario: let's say that you set up two identical mics, one 2" from the speaker, one 2' away. Let's say that you hook up both mics to two identical preamps, set with the same amount of gain. What you get is that the first mic is much louder than the second mic because it's much closer. If you mantain these levels ratio you would probably get away with the comb filtering effect because if the amplitude difference between two signals is >10dB the phase cancellation is heavily reduced. But if you want more room sound and you bring up the far mic you'll get a lot of cancellation. But comb filtering happens only with very short delay times (
Mario this is hilarious. The 3 to 1 rule is something I learned in school and it's kind of amazing to me that you have people saying you're an idiot for following it. If you wanted to simplify your explanation even further, the 3 to rule is just a basic way to make sure that your two microphone capsules are firing the same way at the same time. In it's simplest form, a microphone creates an electrical signal that is either positive or negative depending on whether or not the diaphragm is being pushed or pulled. If they are going in opposite directions when you record, you get phase cancelation in the way you described. That's all the rule is there for. If you want a real world example of it, the best one I can think of is a snare mic'd with a top and bottom mic. the capsules are usually facing each other, and as a consequence the are firing in opposite directions. If you leave them as they are, your snare sounds thin with no bottom end. If you flip the phase on the bottom mic, your low end comes back. The 3 to 1 rule basically does the same thing, but it does it in the room at the time of recording.
EDIT: I forgot to mention that if you want to see a prime example of the 3 to 1 rule in action, take a look at ANY decca tree microphone bar. They have exact measurements on them to minimize phase cancelation, and generally they are designed around the 3 to 1 rule.
Keep up the good work. 😎
Anyone who has ever recorded drums with stereo overheads knows this is a constant struggle. Especially if you like more mono(ish) panning.
Personally, that's part of the reason why I like the Glyn John drum technique. . having each overhead mic on a different plain/axis relative to each and far away from each other other really seems to eliminate a lot of that, and it just sounds rad.
Something important that the Glyn John Technique specifies as well is equal distance from the two "overhead" mics from the snare. This is for the exact reasons I mention in the video. Since the snare is the most important part of the drum kit, this ensures the two microphones are hearing the snare soundwaves at exactly the same moment in time, thus eliminating phasing issues for that part of the kit. Of course this means the toms and cymbals might be slightly out of phase but this is just a compromise as always with drum micing.@@ToneSherpa
Thanks Scott, didn't know you went to audio school. Good point you bring up about the decca tree design. I don't know much about it I am going to have to look up the math/science behind their design, thanks.
You're totally right about the polarity flip for the two mic snare setup this is very important. Unfortunately my mixing board doesn't have a phase switch anywhere!!! So I have no easy way to do this. Very frustrating. This is why I always make sure my mics sound good before they ever get to my mixing board.
@@Mario_DiSantoSome old mics are just wired backwards from factory I've heard. Some old soviet mics and such. Maybe you could use one of those as a snare bottom? Maybe some basic soldering skills on a regular mic and you could modify it to reverse polarity?
@@boyman7823 I've seen guys that do that. Usually they rewire a 57 so they don't have to worry about it.
the start is sooooo good!
Perhaps the real 3:1 rule is the friends we made along the way.
Ha!
Great video, I learned a lot. And I do like the guitar sounds a lot in Little Yellow Bird, nice to get some insight on that.
Glad you dig it my man
Polar pattern of the mics would also come into play if you are trying to avoid phase cancellation based on DB (attenuation) vs phase relation with two sources.
You are a very good educator and I am getting a lot out of these videos. I am making better recordings. Thank you very much. Liked, subscribed, belled and shared.
The 3:1 "rule" just isn't a rule, the problem is that people teach it as a rule and say if you follow it you are going to be "ok" . The entire rule breaks apart as you shorten the distances and get closer to the source, like close micing a guitar cab. if the initial distance is 1cm and the second mic is at 3cm, the 3:1 rule does nothing at all to help keep your phase coherent. I think the 3:1 "rule" was developed when close micing was not the usual practice and farther mics were. At greater distances the higher wavelengths are too close to fold back on each other in a reasonable time domain to cause severe combfiltering and instead your ears, or rather your brain thinks of the more distant mic as actual ambience. when the 2 mics are too close to the source, there is no ratio that will fix that problem because you are mathematically closer to the range of the high end, where you perceive comb filtering in longer wavelengths so if the distances become farther, it is less problematic. If you are recording a line of trumpets spaced 3' apart, anything that is going to fold isn't going to be perceived as comb filtering for the most part . Now, where you are DEAD RIGHT is "who cares". If you put up 2 mics and it sounds good... it IS right. I say ignore the ratio rule because it is misleading and just move your second mic till you like it. Love your videos. Don't be mad, this is and industry built on people saying you are doing it wrong and people doing it anyway.
You make two good points here. One is that this rule is more applicable to mics that aren't close mics. The 1cm and 3cm example is a great example why that is. The distance + amplitude differences is simply to small for there NOT to be an issue.
The second point is that "you should move the two mics until they sound good". This is essentially what I do anyway when I "apply" the 3:1 rule. As I mentioned in the video I'm not actually measuring anything when I do this in the studio. I am more looking at the two mics and mentally saying "okay this is a good starting point because the two mics are reasonably set apart from each other". And then I adjust from there. 6/10 times it sounds good enough for my tastes and I leave their positions as is.
This is all coming full circle now because I'm starting to see WHY so many people are against the 3:1 rule. It gives people false security. I by my own omission don't follow the 3:1 rule per the definition. I'm really just making a visual check to make sure the mics aren't too close and then adjusting from there.
Regardless I think the principle in which the 3:1 rule works is still paramount to understand and I stand by that it only has to do with signal amplitude and not actual distances. I bet I could do some tests to actually test this theory.
Anyway I appreciate the actual response! Cheers mate
@@Mario_DiSanto No prob. I think the thing that people get confused about 3:1 the most is that the actual distance isn't the point, its achieving a discrepancy in amplitude between the mics so your brain can process one as ambience and the other as a direct source. I think the original spec was something like trying to achieve a 10dbB drop in the farther mic, which given the same gain and and using the same mic, 3x the distance naturally achieves. You will see in a lot of old tech writing that it doesn't say 3:1 or 3 times the distance, but "At Least 3 times the distance " and similar descriptions. It's never really been about phase alignment, but psychoacoustics. Keep up the great work. Your videos are a bunch of fun.
As fun as is is to make good music, it is really important to understand the physics, science and math behind the art.
Recording has its own challenges which are already answered, hence the video..
As an electronic producer, I can say most of our issues are in the sub freqs. But the science is still the same. And very very helpful to know and practice.. be good producers guys, great artist.
Top five yt channels right here
Knew some learned more and got a book rec we are out here indeed
Man you gotta get out more often lol
I didn't find any issue with your comments on phase from the previous video. I've recorded a lot of drums and always check phase relationships between the mics on the kit, but I use my ears rather than zooming in on the wave forms in my daw. The snare can be a good indicator to hear phase relationships that are working well together without excess cancellation. If the snare sounds thin, I'll flip the phase switch of a specific channel(s) and that almost always fixes it. If not, I'll go right to the source and adjust the mic position. At this point, I know generally what mics I like on the kit and where to put them in accordance with the sound of the room, so I usually don't have to do a ton of adjustments. I also will record with extra mics in positions that won't always get used in the final mix, but they give me more options. That freedom is the beauty of recording into a daw. I do have a 4 track tape recorder as well though, which I mostly use for character.
I don't record amps with multiple mics very often, but I have heard of the 3 to 1 rule. You've inspired me to give that 2 mic setup a try soon!
The two mic on a guitar cab is a fun setup. I don't always use it because there is more testing involved to get a good sound (for the reasons I talk about in this video). But man when you get everything set right is sounds AWESOME. I really only use it on tracks where I want the guitar to be the focal point of the track.
Cheers
Best video ever, I learned a lot, congrats
If you put one mic in front of your open back amp and another behind your open back amp, the two signals will have big phase cancellation. The same as blending a top and bottom miked snare.
Flip the phase to get the Brown note
Invert the polarity to shit your pants
I've never had any issues, I just put the back mic on a slightly different axis and further away. badda bing badda boom. no phase issues.
there's no getting around the snare issue though. flipping the phase is the only way...
although, sometimes the thinning of the snare tone can be desirable, depending on the song.
There's a Steve Albini video where he talks about what he calls 'time aligning' sources and he has a digital delay he can time down to like 10s of mili seconds and he literally uses an oscilloscope to align two microphones to make his point. It's actually a pretty good video. I guess if you're recording nirvana and have massive budgets and Studers and stuff you've got the time to literally measure the phase alignment at your favorite frequency.
Yes good point. I have seen that video years ago. Like you said if you have big money and time to spend doing that stuff, by all means go ahead and get technical. But for the average home recordist working in a acoustical mess of a recording room you have much bigger problems to worry about and probably don't have the technical knowledge to use an oscilloscope.
Interestingly enough, I've never been a big fan of the sound Steve Albini gets on the records he cuts. This is no offense to him in anyway he obviously has more skill in his toenail than I do entirely. I think I just tend to love the less polished types of recordings. He gets a very "natural" sound is the best way I can describe. I dig the over compressed, blown to bits, garage rock type of vibe. Just a matter of taste of course.
@@Mario_DiSanto totally agree with you about hos sound, not how I would want stuff to sound. But I do love his attitude toward music and a being a big tape nut always warms my heart a bit.
@@Mario_DiSanto There's a Waves plugin called InPhase that does exactly that.
Great video dude!
Thanks for the visit
Love the suspenders homie.
At 21:40 you can see the napkin drawn by Nigel Tufnell, confusing feet for inches. Love it. thanks for sharing your knowledge, it's really helpful. Seen your vids before, have decided to subscribe. Your enthusiasm is winning. It's probably me who's confused, heh.
Haha, "Forget this! Fuck the napkin!". Thanks for watching mate.
Really man! a stripe tie with a patterned shirt...please. :-) I have that book, going to have to pull it out and dust it off. Great video!
Shhhhhh, don't tell the fashion police!
Yeah, phase cancelation won't be significant if the mic recording levels are equal using a 3:1 distance from source ratio because cancelation increases exponentially below a ~6dB difference. Chances are you are not increasing the 2nd mic level to match the first, and the mic distance you like to use of 3~4' ends up being in the proximity boost range of the close mic anyway, further reducing mutual cancelation. Not sure I'd want the example you give here of 2.2kHz cancelation in general, as long as the mic signal levels aren't set close to equal.
One thing I might do is to run pink noise through speaker and use a cell phone FA app to mark where in your room the least bass cancelations are to mic from. Maybe even denote the freqs on pieces of tape placed at the spots.
Ya know that is a good point about increasing mic levels. Technically (if we are to look at this in a simplistic model sense), if I were to increase the gain on my second microphone to a certain amount I would be seeing TOTAL attenuation of the signal at certain frequencies. And when I am "blending" the two mics on my guitar amp this is a factor to consider.
Of course I don't take the time to do any math, I just simply listen with my ears and make a decision on whether it sounds good or not.
Thanks
Another exemple why Rule #1 is : There’s no rule.
It’s more something to be aware of,
to take in consideration. Even more with drums, mic directions, and polar patterns,…
and yes it’s way more than just the total cancellation of that particular freq…
BTW as you know , Top engineers often put different mics side by side on guitar cabs and
blend them.
Id love to hear more engeneer stuff! surfing the soundwaves and calculating sounds fun!! 🙂
Will do Martin
Let me make this simple.
Sound amplitude falls off as the SQUARE of the distance.
That's called the "Inverse Square Law".
What it means in simple terms is that sound amplitude falls off REALLY quickly the farther away you (or the microphone) are.
Put even more simply, the second mic. quickly becomes a non-issue.
Bill P.
Exactly Bill! I probably should have mentioned the specifics in the video because this is a big one. A few things fall off in amplitude as a square of the distance: sound, gravity, magnetics, radiation, light, etc. etc. It's been a while since I opened up one of my engineering textbooks but I believe this is directly due to the increase in area/volume as you move away from a point source in three dimensional space.
Cheers mate
I explained this to singer I had mic'd (well, just placed a mic in front of her), and when she didn't understand because she sang too close and then backed away too much on louder notes, I said: Say your ear is 1 inch from my mouth and I yell, versus if I take 3 feet back and yell, you'll notice the loudness difference way more than Scenario B: I'm 100 feet across the street and yell at you, then yell the same strength but 103 feet away, you'll have trouble telling the difference, well that's how the inverse square law works :)
If the second mic becomes a non-issue because it's amplitude is too low then why having it in the mix at all?
@@mrkite89 the original source signal will be low but there will be reverberation from the room in that mic. Usually a 'room mic' is lower in volume as well.
I was taught to do this equilateral thing... maybe 2:1 or whatever.. both mics at the same distance from the source, like how you setup speakers.. but now I just might have to try this and A-B it; trust your ears, f* yes
I'd be more worried about phase issues if you were using two cardioid, or hyper cardioids. The way you miked the cab with one omni, and one cardioid? Minimizes phase issues.
The omni mic's pickup and what it's "hearing" is SO radically different from the cardioid, you're not going to get a ton of cancellation or comb filtering. I do this with a 635, or and ev do56, or a tube mic in omni all the time. BTW, we used to have almost the exact rig, but it was an M520 console with an MS-16 recorder. Way, way back in the early 90's. My brother now has the M520 in his outbuilding / garage studio. Brings back memories. Good times.
Very true. I really should have touched upon this. My second omni mic is essentially working as a room mic in this two mic setup. Well kinda...2 feet away from a source isn't really a room mic, but same concept. Cheers
Yeah, if it's in the room, and in omni, you're right. It's a room mic :,) Nice original video, and I'm glad to see someone your age with some excitement about tape and consoles etc. Going to subscribe i think! Thanks for putting in the effort. People don't realize how much work it is doing these videos.@@Mario_DiSanto
Are those EV 635A's you're recording the Twin with?
I use the 635a for a lot of things. For the dual guitar microphone setup I usually pair it with an RE-15 or equivalent.
@@Mario_DiSanto Nice! Been trying to find some used ones in Sweden, but no luck yet. I could ofc buy new ones, but where's the fun in that 😄
I often wonder if some of these ‘Jabroni’s’ actually try out the techniques before they comment.
But there absolutely is a Band-Aid in the case where there are two microphones recording the same source, which is manually time-aligning your tracks. Assuming both mics are in the same atmosphere and are subject to the same speed of sound lol. Obviously a great solution for multiple source multiple mic setups like drums.
This is true. I might do a video on this idea because I have had a few people comment this. Probably a lot easier to do in a DAW. I gotta set it up with my delay and oscilloscope. Could be interesting.
LOL
Edit: actually really helpful and not boring, great job!
Great! I was hoping to be informative more than funny haha.
I always look forward to bedroom quickies with Mario.. wait did I say that?
Get in line pal!
If the 3:1 rule is based completely off of decibel levels, why not just attenuate the volume of the 2nd microphone? Its hard to believe that the source you referenced would not explicitly state that the rule is based entirely on decibel level, if that is indeed the case.
Decibel level certainly matters, but there are other factors in play. The change is distance from the source is also going to change the uniformity of the wave forms due to the proximity effect of the microphones and high end roll off.
So, when changing distance, you change both the decibel level and the frequency profile. BOTH matter. Even so, good video. Got me thinking and I could be wrong.
No you are 100% right. Although instead of frequency profile I would say it has to do with the room sound more. Farther away from the source you are, the more room sound you will have, therefore the signal will be sufficiently different from the first close mic.
When I say it has more to do with decibel levels I meant in an ideal world that I modelled on my whiteboard. Simple sine waves that aren't influenced by outside factors such as reverberation due to surroundings or other factors (ie. Proximity effect, room sound, diffraction, etc).
I hope you can agree! Cheers
Yeah, the room noise would definitely be a factor too. I take your point on the sine waves and I think we agree in general.
I'm wondering if the distance would also mean that the fundamentals are more likely to cancel while the higher harmonics are more likely to be spared when combined.
@@dean_the_mystic in the perfect modelled world I just described I would argue no. But in the real world I would say you are correct about the harmonics blending better. Just a gut feeling though.
Does it sound good through what? iPod earbuds or Cerwin JBL’s? I know my stuff! Kinda
I got the digital pedal version of that space echo, does that count ? 😂
You talkin' 'bout the Boss RE-20? How you likin' that thing?
@@Mario_DiSanto Yes the RE-20, with exp.pedal and Warm Audio JetPhaser it sometimes sounds like Hendrix and Hawkwind jamming 🤣
Use a fredman mic method and it's metal ASF
:-D never doubt the holy textes! ;-)
This was a great video! I think it's important that you highlighted that the 3:1 rule is a rule of thumb, not a fascist regime.
By the way, I'm swedish, and 3 feet is roughly 1 meter in the metric system. 1 meter is easier to remember. ;)
Would you please make a video on recording acoustic guitar and wooden acoustic instruments in general?
I would love to hear your opinions on the topic.
Haha you're right. I could do a video on acoustic guitar but I don't have as much experience as electric.
That's why I don't use microphones when recording.
I like this guy
Well I LOVE you.
Looking forward to the Count ? A new single ?
Yessir
wasnt there a 3:1 rule by mixing longdrinks? 😆
3 Parts Rum to 1 part Coca-Cola. That's how I roll.
Thank you noise scientist
Blimey. You wait ages for a Mario DiSanto video then three come along at once. A bit like London buses.
Ya boi is going through a breakup. Gotta do something to keep my mind off things. Cheers.
@@Mario_DiSanto Sorry to hear that man, hope things turn out okay for you.
London Transport has always operated on the 3:1 rule.
🤣🤣🤣
Two mics on a single source is always a bad idea. You are creating a filter no mater what you do. The best you can hope for is an allpass, but that would require 3 or more mics.
I couldn’t agree less, but as long as you’re getting sounds you enjoy, have at it.
There's nothing wrong with phase cancellations. The very nature of stereo is caused by phase differences.
i have not watched the whole video, because tldw) 3:1 rule applies to recording different sources (more than one) with different microphones, not one source (your amp) with different microphones.
Boi...I literally talk about this throughout the whole of the vidya ya bum! The principle in which the 3:1 rule works is on 'signal amplitude'. This works regardless of a single source or multiple source. The same physics/mathematics will apply. Of course in the real world, life isn't exact science, but the principle of attenuation of signals remains true.
Your haircut reminds me of Peter Tork from the Monkees
14:30 free my facial expression at this time to a tee. o_o
Did you hear my terrible singing yet ? But the song is good I think
Are you OK? This is tooooooo funny Mario.
Definitely not OK brother
you missed this, you missed that
If only you had the equipment to show it practically. 🤔
Just uploaded a new song for Carlos Santana
Bedroom quickie 😂😂
I mean, he could have done it in the kitchen. It's right there.
It's weird feeling that someone knows the layout of my house.
Always trust your ears.
You've been yelling at me for 1:30 minutes now without explaining your premise.
Patience is a virtue
@@Mario_DiSantoYou have to start by stating what the 3:1 Rule is, set the context. Then you expand on the established topic.
Something about phase? Okay... So there is some rule.... What is the rule? You immediately jump into phase cancellation without stating the contents of this "3:1 Rule".
Im sorry for me too, as a metrical nerd. ;-) 😀
Are you kidding! All I ever hear anyone say is the Imperial system sucks and the Metric system is superior! Especially in the engineering world. I like to use both for different reasons.
@@Mario_DiSanto of course i think metric ist better, not only i grew Up with it. Im kinda in the engeneering world too. But in the other Hand, being fluent with imperial ist a good Training for your brain. Maybe your faster with calculations, me will be calcu-late... 😎
And bullying americans for their systems is not Superior.
‘Bedroom quickie’…..
Hey bro you cool. Don't make me send the guys with the net. LATER
9:12 "ya metric 'nerds' " -> 79% (4 out of 5) of the world uses the metric system (Liberia, Canada (which uses both) and US. only making 21% of the 8 billion world population). Still funny though, nice video :)
Hmmm seems like a really fancy way of saying 79% of the world are a buncha nerds! Lol thanks for watching
i just don't get why someone who advocates for proper pre-digital studio methods and is prepared to fork out for a Space Echo won't just get a halfway decent analogue delay and use it to buffer the close mic so that the signals are aligned. it just makes no sense. the 3:1 rule is what you do if you literally only have two mics and tape-measure. if you're in a studio, if you're tracking to a multi-track console, if you're gonna spend money on vintage fx units - it just seems really incongruous that you'd use such a compromised approach.
(edit - full disclosure - reason i have a bug up my ass about this is because when i first started recording as a kid, i listened to some know it all guy who was older and cooler than me tell me to use a distant mic as well as my close-mic on my amp, (tbc - this butthole didn't even mention the 3:1 rule, or anything to do with phase issues at all so i'm not saying you're as bad as him!) and for like, about a year i tried this approach into my little four-track and just couldn't figure out why no matter what i did, everything just sounded weaker and lamer than when i just used one mic... so, yeah - i have 'bad mic placement advice' trauma issues that i guess i'm still working through. 😄)
Before I go on, I should mention that I NEVER use two microphones on a single source. Two microphones on any source is never a good idea, mostly because it usually isn't necessary and just brings up potential problems with phasing. That guitar recording method from the last video is the ONLY instance where I break the "less is more" rule.
So why do I break this rule for that guitar recording method? Simple answer...I like the way it sounds. No other reason. It's not because I get better frequency response, or that I am able to control the dynamics better, or whatever specific reason. The simple and sole reason is because..."I like the way it sounds".
So I use this phrase to answer your question of "why not go through a delay to make sure you are minimizing phasing issues"; "I like the way it sounds". Why change something that I like? Music is incredibly subjective where rules are always meant to be broken. Should I change the way something sounds because scientifically it's not the 'correct' way to record it? I certainly don't think so. If I like it, I like it. Simple.
I do have an analog delay that I could delay the signal as you are describing. Perhaps I will do a video on doing just that to demonstrate the "proper" way of doing this (but more importantly to make you happy lol). But my point still stands that I shouldn't necessarily do something just because I'm 'supposed' to. I am a home recordist and I record music for fun. I am not concerned with clients worrying if I am recording something the "right way". No one is paying me to be a professional. I don't have to worry about sending my tracking session to another mixing engineer for them to work with. My only concern is if I like the end product. Ya see what I am getting at here?
In my videos I never try to be the guy that tells people the "best way" to record anything. Which is why I titled the video "My favorite way..." and not "The best way". I just hope to spur some creativity. If I occasionally give some 'out-of-the-box' advice, so be it! It's not like I am putting someone in physical danger. Worse comes to worst they try my method and think it sounds like doo-doo. And fair enough! I have tried people's recording advice before and hated it. It's the experimentation that is fun for me.
But regardless, I am glad for the pushback because it made me think deep about the 3:1 rule, and that is where I come to my own conclusion that it solely (or I guess mostly) has to do with amplitude differences and not distances that the 3:1 rule relies on. Understanding the physics is important even when you aren't following the "best way" so you at least understand what you are doing "wrong".
Cheers
Math is hard.
Just for shits and giggles ask your guys how to pronounce Mario 😂
Yew mist a shit tun of stufff
Damn ya got me!
You are wrong,
Because i like being right,
And telling people they are wrong,
Just for the sake of it 😂
Hey man what's yer problem! Everyone knows that I'm right and you're wrong for the simple fact that I"M SCREAMING LOUDER THAN YOU!
@@Mario_DiSanto challenge accepted (i'm a metal vocalist)
Use one microphone lol