Crap 'phase' info in EQ mag Unbelievable.

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The key is "at least" 3:1. Lots of times you need much higher ratios to get usable tracks, because you will be micing sources with different volumes and using mics with different pickup patterns and frequency response. And of course, you can sometimes get away with less.

I'm glad somebody figured out the math, but cripes it's pretty common sense.

If you have too much bleed, move your shit farther apart, turn it down, or put your mics closer.
 
Yah... it's just a rule of thumb... a starting place. A loose guide.

But it sure helped me out a lot when I first started doing kit set ups. I got so I could listen to the guy or gal's kit and usually get things pretty close the first time (since I usually worked without a second or at least a knowledgeable second, I liked cutting down on my trips from the CR to the floor)... That said, I also remember having a lot of snare/hat issues... that was my Achilles' heel.
 
Regardless of the statement in question (and I've asked the author to respond), the thing that amazes me is that people somehow have the feeling that Printed Things should not be subject to the fact that humans make mistakes. Planes show up late, people go to jail for crimes they didn't commit, you misunderstand something your girlfriend said on the phone, the New York Times prints retractions, movies have continuity errors...but by golly, magazines -- which are put out on an excruciatingly tight schedule by a very limited number of underpaid people -- are supposed to be immune to human error, and if an author makes an error, the editors are supposed to always be able to catch that error.

Now think about an average issue of EQ. There are thousands of statements that could be factually inaccurate or accurate, from whether "DX-7" has a hyphen or not (it doesn't) to, say, elaborations on the 3:1 mic rule. There are also many more statements that might benefit from further explanation, although you have to draw the line somewhere ("A mic is a transducer that converts sound waves to electricity. A transducer is a device that converts one form of energy into another. Energy is neither created nor destroyed so some it may be lost as heat. Heat is caused by...") Sometimes errors of omission are treated as errors of commission. It's like the people who feel a feature that's missing in software is a "bug." It's not a bug, it's a missing feature.

So the magazine has maybe 3 -4 errors in an issue, and as a result someone proclaims on a forum (that has nothing to do with the magazine) how "That magazine is crap! The editor knows nothing! What morons!" (This, of course, is presumably from someone who has never made a mistake in his life and is therefore perfectly qualified to sit in judgement of all those who have strayed from perfection )

What this person apparently doesn't realize is that ALL publications make errors. Period. This is why they print corrections and letters to the editor. There is a mechanism to make sure that any inaccuracies are brought to the readers, and it mystifies me why people don't take advantage of that. The only rationale I can think of is that if magazines DIDN'T make mistakes from time to time, that would undermine someone's feeling of superiority, so in a way, they would prefer that "authoritative" sources be doubted in order to make themselves look better. Or something like that...I'm not a shrink!!

It's like that thread in Pro Sound Web that commented on my phrase-by-phrase normalization technique. The guy who talked about what a horrible article it was and how the technique would destroy dynamic range didn't know the meaning of the word "phrase" from a musical standpoint and didn't understand how normalization works. Then there were people who said normalization is a form of compression, which of course it isn't, and that you should never normalize to 0, which is true some of the time but not all of the time; it depends to a large part on the audio engine the software uses. None of them ever wrote to the magazine or mentioned anything in EQ's forums, which would have been the appropriate venue to correct an "error"...assuming of course that someone's motivation is to help the world understand technology better, not self-aggrandizement.

No one ever did show an error in the article, either, other than repeating things like "You shouldn't normalize! Normalizing is bad!" The only substantive correction was someone pointing out that you shouldn't normalize to 0 (which I never said you should do anyway) if you're going to be using additional DSP and if you're using Pro Tools, because the plug-ins go out through a 24-bit bus. To me, though, that doesn't negate the article: It adds additional useful information for those who use Pro Tools. And it showed someone was more into advancing the state of the art and HELPING OTHERS than stroking his own ego.

It's so easy to criticize, but apparently, it's far more difficult to do so constructively. Please, WE WANT EQ TO BE ACCURATE. If you find an error, or can contribute additional information, send it to us so we can either 1) print a correction, 2) clarify something that's not necessarily wrong but unclear, and/or 3) have a reason to chain the author to a steel cage and let loose an army of hungry rats.

We don't claim to be perfect, but welcome any assistance from people who are -- or even from people who aren't perfect, but knowledgeable about a specific subject :)
 
I have to agree with you Anderton. In fact the letter to the editors and the corrections to past article sections sometimes are the best read.
 
Right on, Craig! You give it to us (including me) because we probably deserve it! :)

I do have to ask, while I have the opportunity, though, on just how the author of that article could make such a crass and rookie mistake to begin with as the one he made about the distance from the amplifier being anything related at all to the 3:1 rule?

It's one thing to understand the human error in it getting past overworked editor. it's another thing to try and understand how that got in there to begin with.

I know you can't answer for the author, and that the onus for that error is more on the author than it is on you. And I, for one, apologize to you for everything I said earlier about editors. But you gotta admit that the error on the part of the author is pretty blatent.

G.
 
I know you can't answer for the author, and that the onus for that error is more on the author than it is on you. And I, for one, apologize to you for everything I said earlier about editors. But you gotta admit that the error on the part of the author is pretty blatent.


Well quite honestly, I don't know the exact wording or intent of the 3:1 rule, as I've always had a good intuitive knowledge of phase and have managed to control phase problems in the studio over the past 40 years or so. My biggest problem had been issues with taking a DI and miked amp sound, until I figured out to delay the DI signal to match the mic distance. So I don't know if Jeff is wrong, right, oversimplified things, or whatever. Hopefully he can speak to that.

What would be really cool is if someone here would write up the specifics of the 3:1 rule with unimpeachable clarity and precision, then submit it to EQ so we could run it in letters.

Anyway, in the previous issue there was a long section in the letters page about how errors occur. In the Townshend interview, mastering engineer Doug Sax's name had been spelled as "Sachs." I've known Doug's work, in fact I've worked on albums that he mastered, and was rather surprised to see the "Sachs" spelling. But JJ Blair and Townshend both spelled it "Sachs."

Well, I figured there was always the possibility that there was an engineer named Doug Sachs I wasn't aware of. So I googled "Doug Sachs" and found a bunch of references from various web sites to such a person, including the management company for a bunch of music industry heavyweights. So ultimately, I figured both Pete and JJ knew who they were dealing with better than I did, so I left it in.

It was wrong, of course...so now I'm a moron for not being aware of the famous mastering engineer Doug Sax :)
 
What would be really cool is if someone here would write up the specifics of the 3:1 rule with unimpeachable clarity and precision, then submit it to EQ so we could run it in letters.
"Unimpeachable" is a pretty high bar to set ;), but I'll give it a jump...as I'm sure a few other here will as well. :)

Good of you to come here personally to plead your case, yet at the same time kinda sorry you had to.

G.
 
This thread certainly caught my attention. I don't know him well, but I happen to be aquainted with Jeff Anderson.
In fact, the the U47 mentioned in the thread below belongs to him.

http://www.homerecording.com/bbs/showthread.php?t=248908

I have heard some of Jeff's work, and he has mastered some projects for a few friends of mine. Many were tracked under less than ideal conditions by amateurs. (I am in that category myself) So he was working with what he received. And so some final products were better than others.

One project that stands out in my mind as a good one is an acoustic guitar recording my son tracked and Jeff mastered for a couple buddies of mine for a PBS special. It came out just gorgeous.

Rest assured that he is a journeyman at his craft.
 
"Unimpeachable" is a pretty high bar to set ;), but I'll give it a jump...as I'm sure a few other here will as well. :)

Good of you to come here personally to plead your case, yet at the same time kinda sorry you had to.

G.

Well, it's all part of the deal. The number of "loved your article about..." posts scattered around the net far exceeds the number of "you're a moron" posts, but in any event, the whole purpose of this particular exercise is to move the art forward. It is dicier editing rather than writing, because I only write what I know about and have researched, so the odds are pretty good it's solid material. But when editing work from another author, I'm on less familiar ground. Jeff has done consistently good work on his reviews -- he really understands and explains the most important aspeect of a unit -- and does excellent recordings. We haven't had any complaints about his work so far, so his batting average is excellent.

The odds are excellent if Jeff presented any misinformation in his article, it was because someone presented that same misinformation to him, or he found that same misinformation somewhere. So, this is an excellent opportunity to get to the right answer once and for all, and spread it far and wide.

It's all about speeding up evolution and spreading knowledge, not who has the baddest slew rate in their power amp!

This whole thing also reminds me of baseball. Let's say an outfielder catches 1,304 fly balls in a row. Then in the playoffs, he drops a ball that lets the winning run score. You can bet the crowd will be yelling "You bum! You're a moron!" instead of "Hey, that's okay, you caught 1,304 in a row and that ain't bad."
 
Hmmmm. Never noticed that. Only one letter's difference in their names.
 
Craig,

Farview started a thread called "Phase Issues" in the Letters to the Editor forum on your BBS. He gave a correct reply to the issue with that article on phase. I have also added a post to that thread that explains the issue, to wit:

"...I'm sorry to say that the article states the 3:1 rule incorrectly and uses an incorrect example to describe it.

The 3:1 rule states that the distance between individual microphones should generally be at least three times the distance from each mic to it's individual source. This applies solely to microphones on seperate sources and is meant to minimize phase issues that can be caused by bleed from nearby sources. It is not meant at all to address phase issues that can be caused by multiple mics on a single source.

The principles behind it are two-fold: First and foremost is the application of the inverse square law relation between distance and volume; i.e. that any time you double the distance from the sound source, the perceived volume level drops to 1/4th the volume at the original distance. The 3:1 rule is designed to try and ensure that any leakage of sound into a microphone from another source is not going to be of high enough amplitude to cause major phase cancellations.

Second, is that the rule helps take advantage of the directional polar patterns of cardioid or figure-8 microphones. The greater the peripheral distance between sources, the more off-angle the source of the leakage and the more it will be rejected by a directional microphone. Again with the same purpose; to reduce the amplitde of leakage so that it's phase effect on the primary source is minimalized.

When double-micing a single source, however - like the git cab example described in the article - neither principle of the 3:1 rule applies. First the inverse square law, while still in effect, only applies if one mixes the two mics at unity gain; i.e. if the engineer actually desires the more distant mic to be a small percentage of the volume of the close mic. As soon as the engineer raises that fader to mix the two tracks, however, he is basically throwing the inverse square law out of the window because he is intentionally raising the volume of the distant microphone.

Second, assuming both mics are directional and pointed more or less towards the cab, and idea of using the 3:1 rule to take advantage of polar pattern rejection also goes out the window.

Third, as far as phase issues go, there are ALWAYS going to be phase discrepencies between two mics of differing distances micing the same source. The only question is at which frequencies those phase issues appear.

Placing one mic 3 inches away from the cab (as in the example) and another 9 inches away only truely affects those particular frequencies whose wavelengths are multiples of 3 inches (and, to a lesser degree, multiples of 1 inch). Move the rear mic one inch further away and now the frequencies that are those with wavelengs that are multiples of 7 inches. A big difference. And netither position will do anything as far as reducing overall phase effects across the spectrum the way that the 3:1 rule does when applied to multiple sources as intended.

Fourth, there is an added element when talking about a speaker cabinet. Which driver are we considering the source? Let's say you have a 4x10 cabinet, for example, and you place the close mic on the upper right speaker because that's the one that sounds the best, and you have the mic right on the grill because that's what gives you the sound you need.

With that setup, any distant mic more than a few inches away from the cabinet is not going to be micing the upper right speaker, but rather the combined sound of all four speaker elements, each of which will be a different distance from the distant microphone (unless the distant mic happens to be alligned with the direct center of the cabinet). This composite sound will have it's own complex phase properites because of the combination of the four physically seperated "sources", and will also have a much more complicated phase relationship with the sounds that the close mic picks up from the single element.

For all these reasons, the 3:1 rule is invalid when talking about multi-miking a single source and is designed and intended only to apply to the relationship between two mics meant for two different sources."

HTH,

G.
 
Glen!! Great stuff! I really appreciate your taking the time and effort to write such a lucid explanation, it made total sense to me. I've passed it along to Matt at EQ to include in the letters section, and have also sent it to Jeff Anderson in case he has any comments.

Props...if you're at AES, I'll buy you a drink. :)
 
Specifically you are looking for at least 9db of level difference. This reduces the level of the comb filtering to less than 1db, which is basically inaudible. Following the inverse square law, tripling the distance to the sound source gives you about 9.5db level drop.:)
 
Glen!! Great stuff! I really appreciate your taking the time and effort to write such a lucid explanation, it made total sense to me. I've passed it along to Matt at EQ to include in the letters section, and have also sent it to Jeff Anderson in case he has any comments.

Props...if you're at AES, I'll buy you a drink. :)
Thanks for the props, Craig :). Unfortunately I am anchored here in Chicago for the time being and will not make the AES. You'll just have to report it all to me in the magazine ;). Of course, if in leiu of that drink you wanted to send me any and all unused UA 2192s you have collesting dust around the offices, I might have a hard time saying no. ;) :D.
boingoman said:
Specifically you are looking for at least 9db of level difference. This reduces the level of the comb filtering to less than 1db, which is basically inaudible. Following the inverse square law, tripling the distance to the sound source gives you about 9.5db level drop.
Thanks for doing the math, boingo :). I was too lazy to do it last night :o.

G.
 
Right on, Craig! You give it to us (including me) because we probably deserve it! :)

I do have to ask, while I have the opportunity, though, on just how the author of that article could make such a crass and rookie mistake to begin with as the one he made about the distance from the amplifier being anything related at all to the 3:1 rule?

It's one thing to understand the human error in it getting past overworked editor. it's another thing to try and understand how that got in there to begin with.

I know you can't answer for the author, and that the onus for that error is more on the author than it is on you. And I, for one, apologize to you for everything I said earlier about editors. But you gotta admit that the error on the part of the author is pretty blatent.

G.
You are way too nice. I would love to see a band record, pay the engineer and then when the mix comes out really horrible, the engineer can claim he is underpaid and overworked. The issue of pay and hours worked should not be ours. We paid (alot) for the magazine. If the work is not up to snuff, the job is substandard. No one asked me if the price I was paying was not enough for the service (magazine, recording, roofing etc.) I pay what they ask. The magazine employees earn what they settled for.
 
wow, very cool of Craig to come in here and plead his case and take a negative thread and turn it into something positive.
Will you be my papa?

:)
 
You are way too nice. I would love to see a band record, pay the engineer and then when the mix comes out really horrible, the engineer can claim he is underpaid and overworked. The issue of pay and hours worked should not be ours. We paid (alot) for the magazine. If the work is not up to snuff, the job is substandard. No one asked me if the price I was paying was not enough for the service (magazine, recording, roofing etc.) I pay what they ask. The magazine employees earn what they settled for.
Those are good points, MCI, but like Lt. Bob, I give Craig Anderton credit for walking straight into this wolves den and nakedly taking the issue head on.

Yes, the error in this case was pretty blatent, and it's frankly hard to excuse straight away, but Craig came in here not trashing us for trashing him, but rather admitting error (more than one, even) and asking for correction so that he could print the correction in the next issue. Frankly, if he were the average forum reader here, he'd just stand by his pride and get into shouting matches with his detractors, or refuse to admit error in the face of facts. He didn't.

Now, the way I see it, we gotta decide whether it's better to just trash Craig and his magazine or to seize the opportunity to step up and right a wrong, in turn giving the subscribers the good info they need in the next issue. Is it better to let the error ride and then curse the fact that it rides, or is it better to actually improve the quality of the information in that magazine?

It took guts to do what Craig did coming in here. And it took maturity for him to admit a bit of ignorance and to ask for an explanation and correction. He's looking not so much just to defend his magazine (though that is of course a big part of it) as he is to improve it. In the midst of much of the Neandrathal behavior that does occur with distressing regularity on in this BBS, I am not ashamed to give Craig what amount of credit he is due for his reaction to an otherwise bad situation, and to help correct it and move on.

G.
 
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