Home |
Search |
Today's Posts |
#81
|
|||
|
|||
|
#82
|
|||
|
|||
ScotFraser wrote:
In the end, everything we do is slightly approximate anyway, so what's a few millimeters this way or that? Possibly quite a lot if looking for complete null with two opposite polarity, separately housed cardioids? -- ha |
#83
|
|||
|
|||
Mike Rivers wrote:
...snip.. Everything in recorded audio is fantasy. Which fantasy do you like? It's all a matter of how "close enough" do you want to get. Even if you could put both microphones in the same place, you couldn't build two capsules closely enough to identical so that they'd cancel completely at all frequencies, from all angles. It's just a way to check whether you're in the ballpark. Grossly mismatched mics will give strange results when used as a stereo pair. Mics that are pretty close will work quite well. -- I'm really Mike Rivers ) In example, I did an MS experiment with a bluegrass group a few weeks ago. They play single mic style so recordings would be in mono. To add some space to the (live) recording (without detracting from their single mic look) I set up two ATM-35 as the S output. [I did do some EQ to help match the S and M response. Note: their single mic is an AT 4033 stuck in an old classic RCA shell, so I don't have a clue what it's response is. (Then too, I wrote a vector analysis program that display phase coherence info. to help with the EQ...) ] Anyway, the added space greatly enhanced the recording. In contrast, a friend's group just did a (single mic) studio recording with reverb to add space ...and to me it just sounds wrong. In the art of recording YMMV is a key phrase. ;-) Later... Ron Capik -- |
#84
|
|||
|
|||
Ty Ford wrote: Then there's the consideration of how the mic bodies might alter the results because of their obstructional presence. For sure. Grills and bodys have very large effects above 10 kHz. That's why I made my DIY MS a front address with an axially symmetric body behind it. It's way too blunt but that's what I had on hand. I've spent very little time at this point evaluating that particular iteration. I know the stereo image is good but haven't characterized the response. If I were to ever build a commercial version of the the 3 capsule M/S I'd be paying special experimental attention to that factor. I'd like to do one with the array at the end of a body shaped like an Earthworks TC30K for example. One of these days. Bob -- "Things should be described as simply as possible, but no simpler." A. Einstein |
#85
|
|||
|
|||
ScotFraser wrote: While they can't be at the same place, they can be at the same distance by placing one atop the other pointing in opposite directions with their diaphragms in the same plane and with that plane passing through the source. BRBR Which is great for sound arriving from a single direction, i.e. an anechoic situation. In any desirable recording venue, obviously the distance thing again becomes slightly approximate. Correct, but my thinking is that for the usual focus of attention, the direct sound from what's arrayed in front and to the sides, it will be pretty optimally captured from an M/S relative delay standpoint and the diffuse or reverberant sound arriving with a signifigant azimuth angle will be what is time skewed. Since that part is naturally skewed with strong frequency dependancy and without any kind of precise image requirements, inaccuracy there shouldn't matter too much. I may be wrong but I don't think the time coherence of ambience is very important. Bob -- "Things should be described as simply as possible, but no simpler." A. Einstein |
#86
|
|||
|
|||
Everything in recorded audio is fantasy. Which fantasy do you like?
It's all a matter of how "close enough" do you want to get. Even if you could put both microphones in the same place, you couldn't build two capsules closely enough to identical so that they'd cancel completely at all frequencies, from all angles. I've liked the sound I get from a U87 in Omni, and a Royer R121 as the bi-directional mic. I doubt the two responses are similar enough for mathematically 'perfect' MS, but the results sound 'good' to me. |
#87
|
|||
|
|||
KyleSong wrote: Everything in recorded audio is fantasy. Which fantasy do you like? It's all a matter of how "close enough" do you want to get. Even if you could put both microphones in the same place, you couldn't build two capsules closely enough to identical so that they'd cancel completely at all frequencies, from all angles. I've liked the sound I get from a U87 in Omni, and a Royer R121 as the bi-directional mic. I doubt the two responses are similar enough for mathematically 'perfect' MS, but the results sound 'good' to me. Where you need to look for 'goodness' with respect to matching is in the spatial distribution of instrument images. If the M and S aren't matched in their response curves then the reproduced image of an instrument that is off axis can get quite blurred with some part of its spectrum in one place and other parts in another place. M/S is intensity based so if relative intensity is varying with frequency so are the image locations. A few dB difference in response at a frequency is like a few dB pan difference at that frequency. Percussion, being especially broad band, is particularly sensitive to this mismatch effect. If, OTOH, you are multi-tracking with MS and your source is always on axis and compact so that you are relying on the S for ambience only you won't be as sensitive to mismatch and the MS panning plugins like Waves' "Stereo Imager" will preserve the spatial coherence while rotating the image. Bob -- "Things should be described as simply as possible, but no simpler." A. Einstein |
#88
|
|||
|
|||
Bob Cain wrote:
If, OTOH, you are multi-tracking with MS and your source is always on axis and compact so that you are relying on the S for ambience only you won't be as sensitive to mismatch and the MS panning plugins like Waves' "Stereo Imager" will preserve the spatial coherence while rotating the image. Thanks for the point - I get it, and hadn't considered that before. generally I do use MS in situations where most of the direct signal is in front of the array, with most of the sides being ambience. In that case, I like the color of the sound I get with the U87 and Royer R121. I'm guessing that the 87 has more top, so perhaps high end will be biased to the middle in this setup. I hadn't encountered the situation of instruments to the side that you're talking about, so if (when) that situation does arise, I'll listen hard for discrepancies such as the ones you describe. Thanks for the education. Kyle |
#89
|
|||
|
|||
I may be wrong but I don't think the time coherence
of ambience is very important. BRBR Right. I think we have a lot of leeway with ambience. I often delay ambience tracks a bit to make them more incoherent, thus less colorizing to the direct tracks. Scott Fraser |
#90
|
|||
|
|||
Possibly quite a lot if looking for complete null with two opposite
polarity, separately housed cardioids? BRBR That not nulled would be in the canine stratus frequency-wise, which is an area where I think we have room for a lot of slop, vis a vis perceived accuracy. Scott Fraser |
#91
|
|||
|
|||
"David Satz" wrote in message om... Sugarite wrote: This is leading towards a debate over whether two matched cardioids are in fact a truer match than either side of a fig-8. I'm of the opinion that the matched card's are a truer match, mostly because you can't as easily test the internal bipolar matching on a mic-by-mic basis like matching two card's. May I take a closer look at this rather mysterious course of logic? If I didn't know better, I'd think you were saying that the ease of testing which you imagine in a thought experiment (!) should take precedence over the accuracy of competent real-world measurements. But even granting that, I think your logical conclusion would be: "If I had to document the front/back symmetry myself, I'd prefer two cardioids. Then I'd have my own way to make the measurements, so I would feel more comfortable trusting the results." Human to human, I could respect that. Still, that isn't quite the same as the broad claim that "cardioids match better than the front and back of a figure 8" (which is what you said). The two statements are about different things--the first one is about your own mindset, while the other one is about microphone capsules, no? **** mindset. This isn't a philosophical issue. Take two cardioids, place them side-by-side in front of any suitably complex sound source. If you oppose the signals from the two mics and all you get is the mics' self-noise, then they're matched with as much certainty as this industry affords. Everything including any aberrations from the two mics being close to each other would show up if they weren't matched close enough to be called "perfect" for any reasonable application. Show me a test that proves any fig-8 can be trusted to that level of precision and I'll certainly consider it. The importance of matched mics for what I do is pretty much paramount. Curves don't cut it. |
#92
|
|||
|
|||
Everything in recorded audio is fantasy. Which fantasy do you like?
It's all a matter of how "close enough" do you want to get. Even if you could put both microphones in the same place, you couldn't build two capsules closely enough to identical so that they'd cancel completely at all frequencies, from all angles. I've liked the sound I get from a U87 in Omni, and a Royer R121 as the bi-directional mic. I doubt the two responses are similar enough for mathematically 'perfect' MS, but the results sound 'good' to me. Part of me wants to burn you at the stake for such a wanton mismatch, but at the same time I applaud your achievement of self-satisfaction despite the technical disparity. It'd be nice to have two groups, rec.audio.pro.theory and rec.audio.pro.practice, because there is so much daylight between the two it's ****ing nauseating. |
#93
|
|||
|
|||
Sugarite wrote:
Take two cardioids, place them side-by-side in front of any suitably complex sound source. I've done that, with several different pairs of like mics, and I did not get a truly decent null. All one must do is listen to how it sounds with both mics in same polarity and then with one mic and notice there is a difference, even with decently matched levels. -- ha |
#94
|
|||
|
|||
Part of me wants to burn you at the stake for such a wanton mismatch, but at
the same time I applaud your achievement of self-satisfaction despite the technical disparity. Oooh burned Wantons - not a good grade in cooking school, but they taste SO good Seriously, thanks for the post. I really DO have good ears, and I really DO like the sound. I generally use it for drum ambience, so the color is a matter of taste. If I was doing this with a string quartet, especially one that was spread out around the microphone, then I'm sure I would choose differently. The color of the room ambience on the drums is really great with this combination, and like I said before, there isn't any source that's placed outside of the front of the array, so the stereo placement isn't being compromised. |
#96
|
|||
|
|||
|
#97
|
|||
|
|||
|
#98
|
|||
|
|||
The difference between how a KM184 and a KM140 sound, as according to
Neumann the capsule being placed a few millimeters different is the only difference techincally between the two mics, one of which you have said you much prefer over the other.... g BRBR Actually I've never used a KM184 in a critical situation, so I don't have an opinion about them. You must be thinking of some other guy named Scott. Scott Fraser |
#99
|
|||
|
|||
ScotFraser wrote:
The difference between how a KM184 and a KM140 sound, as according to Neumann the capsule being placed a few millimeters different is the only difference techincally between the two mics, one of which you have said you much prefer over the other.... g BRBR Actually I've never used a KM184 in a critical situation, so I don't have an opinion about them. You must be thinking of some other guy named Scott. It was probably me. I like the KM140 better. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
#100
|
|||
|
|||
(ScotFraser)
Actually I've never used a KM184 in a critical situation, so I don't have anopinion about them. You must be thinking of some other guy named Scott. Actually you did say so once Scott, at least by deductive reasoning. You said in a U87 thread that comparing a KM184 to a Scheops CM62 was unfair due to the cost differential, that a comparison to a KM140 was a closer comparison, and that you "slightly prefer the depiction of the upper bass range of the KM140." Not to bust your chops or anything... g Will Miho NY Music & TV Audio Guy Audioist / Fox News "The large print giveth and the small print taketh away..." Tom Waits |
#101
|
|||
|
|||
"Sugarite" wrote in message ... **** mindset. This isn't a philosophical issue. Take two cardioids, place them side-by-side in front of any suitably complex sound source. If you oppose the signals from the two mics and all you get is the mics' self-noise, then they're matched with as much certainty as this industry affords. Everything including any aberrations from the two mics being close to each other would show up if they weren't matched close enough to be called "perfect" for any reasonable application. Show me a test that proves any fig-8 can be trusted to that level of precision and I'll certainly consider it. The importance of matched mics for what I do is pretty much paramount. Curves don't cut it. I have to wonder how you could get the two mics to occupy the EXACT same space at the same time to perform such a test? Side by side don't cut it either. TonyP. |
#102
|
|||
|
|||
"TonyP" wrote in message
u I have to wonder how you could get the two mics to occupy the EXACT same space at the same time to perform such a test? Side by side don't cut it either. As close as you'll get practially might be obtained by using miniature mics. I followed up on some recent posts about Knowles mics that Digi Key has in their catalog and found that they are actually 0.1" OD. Those were omnis, but I think they also have some really small directional mics in their catalog. My point being that 1" mics quite obviously can't be coincident at paractial audio frequencies, and IME neither can 1/2" mics. However, practially nearly coincident up to say 10 KHz could solve a lot of problems. The wavelength of 10 KHz is something like 1.3 inches, so mics that are 0.1" center to center are still about 30 degrees apart in terms of phase. The good news is that 30 degrees is a long ways from 180 degrees. The cosine of this angle is almost 0.9, so cancellation on the order of 20 dB at 10 KHz seems possible. |
#103
|
|||
|
|||
"Arny Krueger" wrote in
: The wavelength of 10 KHz is something like 1.3 inches, so mics that are 0.1" center to center are still about 30 degrees apart in terms of phase. The good news is that 30 degrees is a long ways from 180 degrees. The cosine of this angle is almost 0.9, so cancellation on the order of 20 dB at 10 KHz seems possible. Also, we're not interested in the stereo effect of vertical spacing. Most sources are spread in the horizontal plane, so having mics coincident vertically is usually enough. A pair of side address mics, one atop the other can get very close vertically and almost precisely aligned horizontally (to the limitation of the width of the capsule). |
#104
|
|||
|
|||
Arny Krueger wrote:
As close as you'll get practially might be obtained by using miniature mics. Whereas in practicality we might want to use some other type of mic. I guess I'm just sceptical about the usefulness of trying to null separate, real world and of various size, cardioid mic pairs. IME it hasn't worked well. Maybe that's just another reason folks bother to build anechoic chambers. -- ha |
#105
|
|||
|
|||
Do you roll off the low end a lot on your ambient tracks Scott?
BRBR I don't really have a blanket policy on that, it's really on a case by case basis, but probably a low rolloff is unconsciously in place due to mic choice, since I'm more interested in mid & higher response in the ambient tracks. Scott Fraser |
#106
|
|||
|
|||
hank alrich wrote:
Arny Krueger wrote: As close as you'll get practially might be obtained by using miniature mics. Whereas in practicality we might want to use some other type of mic. I guess I'm just sceptical about the usefulness of trying to null separate, real world and of various size, cardioid mic pairs. IME it hasn't worked well. Maybe that's just another reason folks bother to build anechoic chambers. -- ha All this "phonons dancing on the head of a pin" stuff has me wondering what has become of the usual mantra of this group: use your ears... ? If one needs to account for and correct every little phase anomaly in the system before they record they'd never get any recording done. In my experience theory helps but the real proof is in the experimental (or in this case recording) results. [OK, I'll admit some of these techno-flame-wars are fun to follow. ] Later... Ron Capik cynic in training -- |
#107
|
|||
|
|||
Ron Capik wrote:
All this "phonons dancing on the head of a pin" stuff has me wondering what has become of the usual mantra of this group: use your ears... ? I guess a paraphrasation of what's talking here is trying to get at audible image anomalies when using an M/S config. The tangent developed around the question of useful null from separate cardioids. My points remain that I have no interest in laboratory results using the tiniest available cardioids because the liklihood of me wanting to use those in recording work is low, and that I have little faith in the achievement of null with the real world mics, having been there and done that. If one needs to account for and correct every little phase anomaly in the system before they record they'd never get any recording done. Right, but in the context of stable imaging across the spectrum, little phase anomalies can make larger than expected differences. In my experience theory helps but the real proof is in the experimental (or in this case recording) results. Amen. [OK, I'll admit some of these techno-flame-wars are fun to follow. ] You're a sick man, Ron, but you knew that already. Later... Ron Capik cynic in training The Cynical Olympics, new on FOX! -- ha |
#108
|
|||
|
|||
Ron Capik wrote:
All this "phonons dancing on the head of a pin" stuff has me wondering what has become of the usual mantra of this group: use your ears... ? I guess a paraphrasation of what's talking here is trying to get at audible image anomalies when using an M/S config. The tangent developed around the question of useful null from separate cardioids. My points remain that I have no interest in laboratory results using the tiniest available cardioids because the liklihood of me wanting to use those in recording work is low, and that I have little faith in the achievement of null with the real world mics, having been there and done that. If one needs to account for and correct every little phase anomaly in the system before they record they'd never get any recording done. Right, but in the context of stable imaging across the spectrum, little phase anomalies can make larger than expected differences. In my experience theory helps but the real proof is in the experimental (or in this case recording) results. Amen. [OK, I'll admit some of these techno-flame-wars are fun to follow. ] You're a sick man, Ron, but you knew that already. Later... Ron Capik cynic in training The Cynical Olympics, new on FOX! -- ha |
#109
|
|||
|
|||
Ron Capik wrote:
In my experience theory helps but the real proof is in the experimental (or in this case recording) results. I agree. Knowing and understanding audio theory will help you make informed decisions, and give you a good set of options to choose from. Ditto experience. But each of these is only a starting point. There is not "Art by Number" method that will produce great results every time. This is not an argument for ignorance. You must have both: a good understanding of what is happening and is possible, AND an open mind and open set of ears to hear how its sounding THIS time. In my opinion, the hardest thing about any art is to keep your experience/technique handy, but not in the driver's seat. This means avoiding the bias that knowledge brings, while still using it to your advantage. For instance, if you spend $4,000 on a beautiful tube compressor, and you come to a track that is the sort of thing that you bought that piece FOR, it is a VERY difficult thing to admit to yourself (and hear) that in this case, the device is not working as well as something else. Another example is avoiding the theoretical 'misuse' of unmatched microphones in an M/S array that just happens to sound 'good'. The dilemma is in having good knowledge / experience to draw from, and listening like its the first time, all at once. This is the basic struggle of any artist in any medium. To have the chops to do it well, and at the same time, to let your subconscious voice lead the way. The purpose of art is to create an emotional (and / or intellectual) response in the audience. Technique helps in creation, but it is the result that matters. You will do better work on a more consistent basis with knowledge. But your work will be best if it speaks to humanity, and that is something that cannot be quantified in technique alone. Since I don't believe that there has EVER been a recording that sounded like musicians playing live in a room, I think that all recordings are on some level impressionistic. Even if the result is intended to mimic a natural experience, it may well be through the judicious application of several processes that the most "natural" feeling recording results. Based on this belief, I don't think you can argue science past a certain point in audio. You can argue HOW something works, but it is how it sounds that matters in the end. Of course "how it works" informs "how it sounds", so again, this is not an argument, or an excuse for ignorance. I'm not saying "**** science, it only matters how it sounds" but I AM saying that science alone cannot describe the entirety of what we are all trying to do here, and that when theory becomes in opposition to results that are ideal for a certain musical application, that the science must step aside to accommodate the human artistic experience. |
#110
|
|||
|
|||
Ron Capik wrote:
In my experience theory helps but the real proof is in the experimental (or in this case recording) results. I agree. Knowing and understanding audio theory will help you make informed decisions, and give you a good set of options to choose from. Ditto experience. But each of these is only a starting point. There is not "Art by Number" method that will produce great results every time. This is not an argument for ignorance. You must have both: a good understanding of what is happening and is possible, AND an open mind and open set of ears to hear how its sounding THIS time. In my opinion, the hardest thing about any art is to keep your experience/technique handy, but not in the driver's seat. This means avoiding the bias that knowledge brings, while still using it to your advantage. For instance, if you spend $4,000 on a beautiful tube compressor, and you come to a track that is the sort of thing that you bought that piece FOR, it is a VERY difficult thing to admit to yourself (and hear) that in this case, the device is not working as well as something else. Another example is avoiding the theoretical 'misuse' of unmatched microphones in an M/S array that just happens to sound 'good'. The dilemma is in having good knowledge / experience to draw from, and listening like its the first time, all at once. This is the basic struggle of any artist in any medium. To have the chops to do it well, and at the same time, to let your subconscious voice lead the way. The purpose of art is to create an emotional (and / or intellectual) response in the audience. Technique helps in creation, but it is the result that matters. You will do better work on a more consistent basis with knowledge. But your work will be best if it speaks to humanity, and that is something that cannot be quantified in technique alone. Since I don't believe that there has EVER been a recording that sounded like musicians playing live in a room, I think that all recordings are on some level impressionistic. Even if the result is intended to mimic a natural experience, it may well be through the judicious application of several processes that the most "natural" feeling recording results. Based on this belief, I don't think you can argue science past a certain point in audio. You can argue HOW something works, but it is how it sounds that matters in the end. Of course "how it works" informs "how it sounds", so again, this is not an argument, or an excuse for ignorance. I'm not saying "**** science, it only matters how it sounds" but I AM saying that science alone cannot describe the entirety of what we are all trying to do here, and that when theory becomes in opposition to results that are ideal for a certain musical application, that the science must step aside to accommodate the human artistic experience. |
Reply |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Forum | |||
Question regarding Phantom Power | Pro Audio | |||
Question regarding Phantom Power | Pro Audio | |||
Question regarding Phantom Power | Pro Audio | |||
newbie question - aardvark q10 + external mixer? | Pro Audio | |||
RCA out and Speaker Question in 2004 Ranger Edge Question | Car Audio |