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#41
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MS Proximity Problem
On 14-12-2015 22:23, Scott Dorsey wrote:
Peter Larsen wrote: On 14-12-2015 14:45, Frank Stearns wrote: As I've probably commented before, I at one time used M-S extensively but like X-Y and to a lesser extent ORTF found that M-S does not offer the depth image possible with 50 cm-spaced omnis. I used that a lot for a chamber music festival with extremely good results, including good tolerance of being close to the sound sources. My objection is that the "sense of depth" that you get in the recording is unrealistic and not like the sound in the actual hall. Lots of people like it, though, and it's less extreme than the Mercury triad. It has rendered a concert band in a church very well for me before the intermission, a friend had a suggestion for a minor change of the mic setup - angling them outwards, thus also increasing the effective distance between capsules - and that made it a sonic mess, but yes, the woodwind got clearer at the cost of perspective and spatial rendering. I should not have been polite and I have not been open to suggestions of changes in the intermission since. The distance from sublime to ordinary is not long. When I choose not to bring omnis, then it is either because of recording in an unknown space or because of known problems with audience or other noise, cardioids give me about 6 dB less "room or other" noise and they are hardly ever a "wrong choice", omnis can be. --scott Kind regards Peter Larsen |
#42
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MS Proximity Problem
On 14-12-2015 22:30, geoff wrote:
On 15/12/2015 2:26 a.m., Mike Rivers wrote: The usual way to do this in a DAW program is to "group" the two side signals in the software mixer. Pan one full left, the other to full right, and control them both with a single software fader. Then start your "mix to stereo" with just the mid channel and listen on speakers as you bring up the level of the side signals. Stop when you get the width you want. Slightly O the specific T, but as an aside with MS, I find the control is so powerful, I can never actually decide when the width is how I want it ! You want a stable center, no hole in the middle and no "pressure at the ears", widen until center unstable and "pressure at the ears" and narrow ye smalle bet and you're there. Just as when positioning a main pair, except that you can't listen for how much ambience to add or subtract by lifting or lowering the mics. Interestingly a mic stand has most of the controls a well equipped channel strip has, except monitor sends perhaps. geoff Kind regards Peter Larsen |
#43
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MS Proximity Problem
Frank Stearns wrote:
"Gary Eickmeier" writes: Is there some other way to do it that you are talking about? Not sure what you're asking, but electrically, a single channel panned center should be *identical* to that same single-source channel duplicated and applied to a hard left/hard right pan on two channels. What do you think is happening internally at a pan pot??? When centered, it's dumping equal signal level to the left and right summing busses (allowing for any non-linearities in the pan pot itself. In a DAW, center is center and should be a non-issue in terms of subtle hardware errors. But with HW, that's why you use meters). Panning M center does work with M-S as described; I have 100s of recordings to prove it. Er well, now that you bring it up.... so you are just putting the M at center and the S to the left and the -S to the right? Well, I can't think of any reason why not, I just never thought of that. All I know is that with MS the left channel is composed of M and S, the right channel M and -S, so that is what I have been doing. BTW for all, I did the concert band recording and it went perfectly, and it seems to be a near perfect surround recording. Various times in the show there were distinct rear channel effects such as audience singalongs, Santa coming in from the back of the auditorium, audience interruptions, and it was all correctly channelized in my system. Very enjoyable. Gary |
#44
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MS Proximity Problem
I neglected to mention that I always look at the Phase Analysis window
(lissajeous pattern) to see the stereo signal and surround information. In the case of my current recording of the concert band, it looks like a football that is evenly centered on the crosshairs. This means that there is a lot of out of phase information, giving good surround sound, but also decent center fill. I might try to add a little more center fill, but this recording is very good for what I am after. The listening in the theater room confirms all of this. I'm having a ball! Gary "Mike Rivers" wrote in message ... On 12/14/2015 6:23 AM, Tom McCreadie wrote: Mike Rivers wrote: Also, understand that M-S doesn't have as accurate imaging as X-Y Really, Mike, how on earth can you justify that? An M-S would in general actually give a more accurate representation of centered images. As ever, of course, the imaging quality depends on the degree of off-axis response-raggedness of real life mics. And that's exactly my point. A mid mic that has a little bump in its polar response on one side of center that isn't matched on the other side, or a side mic that isn't perfectly symmetrical (a number of modern ones are intentionally built that way) will throw off the image accuracy. It takes a lot of care in placement, which means careful listening, to get it right. On the other hand, reasonably well matched cardioid mics aren't hard to find, and for the kind of recordings that Gary is making, he's likely to get more consistent results. -- For a good time, visit http://mikeriversaudio.wordpress.com |
#45
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MS Proximity Problem
Of course not.
Gary wrote in message ... To the OP, was there ANY kind of AGC engaged while you were recording? Mark |
#46
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MS Proximity Problem
On Monday, December 14, 2015 at 12:41:42 PM UTC-7, Gary Eickmeier wrote:
Frank - you said something that bothers me - see below - you said that "My assumption has been that you're recording raw M and raw S, and *not* decoding to L and R at the time of recording. Rather, the "conversion" to L & R is done in post using: " - a mid channel, panned center (likely a cardioide but I have used omnis to good effect, particularly those with some HF directionality)" No, you don't pan the M channel to center, you pan the M and the straight S to the left for the left channel, and the M and the inverted S to the right channel. Is there some other way to do it that you are talking about? Gary "Frank Stearns" wrote in message ... "Gary Eickmeier" writes: Jason, just the flexibility of the post processing of MS. If you record XY, you must decide on the included angle, which maybe wouldn't always be 90 degrees - would it? Frank, what are you meaning by calibration? The gain settings? No, my gain knobs are not accurate, compared to each other. I set gains by the meters, not the knob numbers. This may create a slight problem in MS recording because all I know to do is make the gains equal during recording, which may not be accurate as far as the stereo spread when all is said and done. My starting point in the mix is to set the M and S gains to be equal, then to move the ratios up or down to get center fill right. My assumption has been that you're recording raw M and raw S, and *not* decoding to L and R at the time of recording. Rather, the "conversion" to L & R is done in post using: - a mid channel, panned center (likely a cardioide but I have used omnis to good effect, particularly those with some HF directionality) - a side channel, initially recorded with a Fig 8 mic, panned hard left, - an exact copy of the side channel but with the polarity flipped, panned hard right. That copy might be a polarity flip on duplicated data, polarity flip on a channel strip Y'd from the raw S channel, and so on -- whatever method you use to get a second duplicate channel off the source S, just flipped. It's important to "calibrate" the S+ and S- channels. When temporarily panned center, you should have complete cancellation and hear nothing. If you hear something faintly coming through, the S+ and S- channels are out of cal.. Adjust levels and EQ to get the best possible cancellation. This is much more likely a problem when decoding with hardware (channel strips of a console) because of minute variances in component tolerances among channels. Also, it's nice to have field monitoring while still maintaining that raw M & S recording, so you've perhaps set up channel strips in your field monitor console as noted above. As far as the relative level of M and S, it does not take much S to get a nice stereo spread so often the S faders will be 6-15 dB lower than M. As I've probably commented before, I at one time used M-S extensively but like X-Y and to a lesser extent ORTF found that M-S does not offer the depth image possible with 50 cm-spaced omnis. I still use M-S when overdubbing group vocals in multiple passes. I can record each pass with a nice stereo image, but then in post will often throw away the S channels and pan the M of each pass differently to get a more striking L/R spread of those vocals. YMMV. Frank Mobile Audio -- . What I do is I take the "M" signal and put it in one channel (either Software or Analog board and pan that to center. I then take the "S" signal and either duplicate it to two channels in software and invert one of the channels, or on a board, I would split the the S signal to two channels and invert one of them. The + channel is Panned to Left and the - channel is panned to hard right.. To check the accuracy of the S arrangement, mute the M channel and listen to S+ and S- in mono. They should absolutely cancel. The other thing that I can do is just run the signals through an MS decoder in software, but any of the three works just fine. The way I like to think of MS is that the Left channel Is mid plus (+S) and right is Mid + (-S). To get a decent sound, it is imperative that your "M" microphone is in a place that sounds good and if you are using a cardioid that your pickup is limited to about 120 degrees. The "S" signal is the additional ambience and directionality. I find MS to be a little sterile by itself and when I use it as a main pickup array, I usually add a pair of flanking microphones, commonly two figure 8's with the null pointed forward toward the ensemble. about 15 feet back and within 20' of the main array. |
#47
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MS Proximity Problem
Richard Kuschel wrote:
What I do is I take the "M" signal and put it in one channel (either Software or Analog board and pan that to center. I then take the "S" signal and either duplicate it to two channels in software and invert one of the channels, or on a board, I would split the the S signal to two channels and invert one of them. The + channel is Panned to Left and the - channel is panned to hard right.. To check the accuracy of the S arrangement, mute the M channel and listen to S+ and S- in mono. They should absolutely cancel. The other thing that I can do is just run the signals through an MS decoder in software, but any of the three works just fine. The way I like to think of MS is that the Left channel Is mid plus (+S) and right is Mid + (-S). To get a decent sound, it is imperative that your "M" microphone is in a place that sounds good and if you are using a cardioid that your pickup is limited to about 120 degrees. The "S" signal is the additional ambience and directionality. I find MS to be a little sterile by itself and when I use it as a main pickup array, I usually add a pair of flanking microphones, commonly two figure 8's with the null pointed forward toward the ensemble. about 15 feet back and within 20' of the main array. MS sterile? You must not be listening to the result in surround. I have found that MS makes an incredible surround encoder. The out of phase stuff goes way over to the sides and rear if you listen in DPL-II on a well balanced system.k I think I must be mixing in too much S, and I can get some extreme L or R instruments decoding to the rear, but by and large I am getting a great surround that can amazingly decode to the sides, like all of the textbooks say can't be done. Well I'm sorry, I am doing it! My main question about MS has always been, how do you know how much gain to put in the S channel to make it perfectly decode to XY as if it was recorded with two cardioids at 90 degrees? Just by listening? What should the Lissajeaous pattern look like? I am thiniking that my surround sound success may be due to the mike patterns between my M and S not having much overlap. I am using the AT-2050 multi-pattern large diaphragm cylindrical shaped mikes, the M set to cardioid and the S to Figure 8. It would probably be a different story if I set the M to omni. I think I don't want to set the M to Figure 8 because then the rear channels would be a reversal - mathematically, the Left channel would be composed (or comprised) of -M + (-S) and the right of -M + S. Something like that. Anyway, it has the effect of reversing the right and left channels, compared to the front. I have tried it. Can't find my New Stereo Sound Book at the moment. Streicher has some good info on MS. Gary |
#48
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MS Proximity Problem
On 12/17/2015 10:28 AM, Gary Eickmeier wrote:
MS sterile? You must not be listening to the result in surround. I have found that MS makes an incredible surround encoder. The out of phase stuff goes way over to the sides and rear if you listen in DPL-II on a well balanced system.k I don't know what "listen in DPL-II" means (Dolby Pro Logic, maybe?), but I can tell you that the M-S mic setup was never intended to be any sort of a surround encoder. If you're using it for that purpose, you're on your own. Honestly, I doubt that you'll get nothing but arguments and diversions from this newsgroup. I think I must be mixing in too much S, and I can get some extreme L or R instruments decoding to the rear, but by and large I am getting a great surround that can amazingly decode to the sides, like all of the textbooks say can't be done. Well I'm sorry, I am doing it! Can you describe your signal path? Where are you getting the signal that drives the rear speakers? If this is the DPL-II decoder of which you speak, perhaps a button you press on a receiver? Surround decoders are designed to take in conventional left/right stereo and derive side and rear channels from it. If it's designed to take left and right and you're feeding it mid and side, or even left and right with a hole in the middle, then what you'll get out of it is bound to be goofy. Are you converting your mid and side channels to left and right with your computer, and then running those through a surround encoder to get your rear channels? Do they sound like good stereo when you just listen to the left and right derived from your mid and side recording? My main question about MS has always been, how do you know how much gain to put in the S channel to make it perfectly decode to XY as if it was recorded with two cardioids at 90 degrees? Just by listening? That's the best way. Equal parts is always too much side. Generally the side 3 dB lower than the mid is a good place to start. This is what's used as "normal" when you have a hardware M-S decoder or a stereo mic that has mid and side pickup but spits out left and right. But since the audio content of the side channel is substantially different from the mid channel, you can't reliably go by the numbers or meter readings. As I suggested before, start with no side channel and then bring it up symmetrically (+S and -S added equally to the mid channel) until it sounds right. What should the Lissajeaous pattern look like? Like any other stereo mic setup - scrambled eggs. However, when you have too much side (or not enough mid), you'll see it tilt toward the left I am thiniking that my surround sound success may be due to the mike patterns between my M and S not having much overlap. I am using the AT-2050 multi-pattern large diaphragm cylindrical shaped mikes, the M set to cardioid and the S to Figure 8. It would probably be a different story if I set the M to omni. I think I don't want to set the M to Figure 8 Those are both configurations that have been used. The arithmetic works out for all of them, it's just that the results will be different. But by using an omni or a bi-directional mic for the mid signal, you'll get more sound from the back of the room - just the way looks like it would work when you look at the polar diagrams. Sometimes that's helpful, sometimes it isn't. If you're going into a real surround decoder, it might be useful to feed it some real rear sound and hope it can figure out how to use it. I think it's a good thing that you're experimenting, but since nobody here seems to be doing what you're doing, it's hard to be really helpful. -- For a good time, visit http://mikeriversaudio.wordpress.com |
#49
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MS Proximity Problem
"Mike Rivers" wrote in message ... On 12/17/2015 10:28 AM, Gary Eickmeier wrote: MS sterile? You must not be listening to the result in surround. I have found that MS makes an incredible surround encoder. The out of phase stuff goes way over to the sides and rear if you listen in DPL-II on a well balanced system.k I don't know what "listen in DPL-II" means (Dolby Pro Logic, maybe?), but I can tell you that the M-S mic setup was never intended to be any sort of a surround encoder. If you're using it for that purpose, you're on your own. Honestly, I doubt that you'll get nothing but arguments and diversions from this newsgroup. Well, it started with my listening to everything in surround, Dolby Pro Logic II. I think we all know that it basically takes the difference information, or out of phase signals, and decodes it to the sides/rear surround channel, much like the old Scheiber circuit. So when I listened to my MS recordings (and those of friends) I was wowed by a playback that decoded the surround sounds that I heard at the location correctly! I think we all know about the MS reputation for spaciousness, but this was a bonus! And it seems logical - the S signal is pure out of phase information. If you had just that, panned left and right, it would all decode to the rear. Or should I say rear/sides, because, for example, an instrument that was strictly (mostly) picked up by the right lobe of the side mike, and would therefore decode to the right channel only after dematrixing, would appear in the right channel. A sound at the rear of the microphones would be a pure out of phase signal, and decode straight back. So it would be more like a rear hemisphere of sound. Then, when you mix in some M, you get the in phase front sounds to decode to the front to fill in the circle of the surround sound. Get the ratios just right, and everything comes from where it should. I think I must be mixing in too much S, and I can get some extreme L or R instruments decoding to the rear, but by and large I am getting a great surround that can amazingly decode to the sides, like all of the textbooks say can't be done. Well I'm sorry, I am doing it! Can you describe your signal path? Where are you getting the signal that drives the rear speakers? If this is the DPL-II decoder of which you speak, perhaps a button you press on a receiver? Surround decoders are designed to take in conventional left/right stereo and derive side and rear channels from it. If it's designed to take left and right and you're feeding it mid and side, or even left and right with a hole in the middle, then what you'll get out of it is bound to be goofy. No, it is as described above. A normal MS recording, dematrixed down to stereo, can be heard as surround sound when listened to in DPL-II with a balanced system. By balanced, I mean an out of phase signal plays at the same loudness as an in phase signal - like, when you play one of those channel identification recordings at the in phase vs out of phase section, the in phase comes from front center, the out of phase from rear center. I have made a test recording in which I mix my voice to travel all around the room. This is the best matrix surround I have heard. Are you converting your mid and side channels to left and right with your computer, and then running those through a surround encoder to get your rear channels? Do they sound like good stereo when you just listen to the left and right derived from your mid and side recording? Yes and yes. My main question about MS has always been, how do you know how much gain to put in the S channel to make it perfectly decode to XY as if it was recorded with two cardioids at 90 degrees? Just by listening? That's the best way. Equal parts is always too much side. Generally the side 3 dB lower than the mid is a good place to start. This is what's used as "normal" when you have a hardware M-S decoder or a stereo mic that has mid and side pickup but spits out left and right. But since the audio content of the side channel is substantially different from the mid channel, you can't reliably go by the numbers or meter readings. As I suggested before, start with no side channel and then bring it up symmetrically (+S and -S added equally to the mid channel) until it sounds right. Pretty much my experience as well. What should the Lissajeaous pattern look like? Like any other stereo mic setup - scrambled eggs. However, when you have too much side (or not enough mid), you'll see it tilt toward the left I'm thinking there must be several versions of the Lissajeous pattern out there. Mine is the Phase Analysis window in Audition 2. It looks like a scrambled eggs circle in a polar plot about the center of the crosshairs on the screen. There is a bouncing green ball that indicates the center of balance between left, right, front, and rear (out of phase) sounds. This is a super big help in predictiing how my mix will decode in surround. I think what I want is a pattern that is symetrical about the crosshairs. I am thiniking that my surround sound success may be due to the mike patterns between my M and S not having much overlap. I am using the AT-2050 multi-pattern large diaphragm cylindrical shaped mikes, the M set to cardioid and the S to Figure 8. It would probably be a different story if I set the M to omni. I think I don't want to set the M to Figure 8 Those are both configurations that have been used. The arithmetic works out for all of them, it's just that the results will be different. But by using an omni or a bi-directional mic for the mid signal, you'll get more sound from the back of the room - just the way looks like it would work when you look at the polar diagrams. Sometimes that's helpful, sometimes it isn't. If you're going into a real surround decoder, it might be useful to feed it some real rear sound and hope it can figure out how to use it. I think it's a good thing that you're experimenting, but since nobody here seems to be doing what you're doing, it's hard to be really helpful. I have done some experiments in an anechoic (outdoor) environment, making noises all around the mike stand with various MS patterns, and it works pretty much as described above. This is not custom recording just for my playback system, because several friends have played my recordings in both surround and straight stereo, and they said they sound great either way. I also have a few recordings from them, and they have the same interesting surround capabilities. Talk about a compatible two channel system! Obviously it won't sound identical to all customers, but it will sound decent to Joe Blow on his boombox or earbuds or in the car as well as the audiophile listening in surround. If anyone would like a CD, just send me your mailing address. Gary |
#50
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MS Proximity Problem
On 12/17/2015 2:50 PM, Gary Eickmeier wrote:
we all know about the MS reputation for spaciousness, but this was a bonus! And it seems logical - the S signal is pure out of phase information. If you had just that, panned left and right, it would all decode to the rear. Or should I say rear/sides, because, for example, an instrument that was strictly (mostly) picked up by the right lobe of the side mike, and would therefore decode to the right channel only after dematrixing, would appear in the right channel. A sound at the rear of the microphones would be a pure out of phase signal, and decode straight back. "In theory, theory and practice are the same. In practice, they usually aren't" - me The problem with this thinking is that the bi-directional mic picks up (ideally) nothing from the front or the rear, only from the sides. So the best you can do is send the decoder two channels of side material, out of phase. What it does with that, Dolby only knows. I'm thinking there must be several versions of the Lissajeous pattern out there. Mine is the Phase Analysis window in Audition 2. It looks like a scrambled eggs circle in a polar plot about the center of the crosshairs on the screen. There is a bouncing green ball that indicates the center of balance between left, right, front, and rear (out of phase) sounds. There's only one Lissajous pattern, with the left signal sweeping horizontally and the right signal sweeping vertically. There are a number of "stereo" or "phase" displays, of which you're apparently looking at one. I suppose if you learn to interpret it, it can be helpful, but I don't have a clue as to what it means in practice. When I had my remote truck and did a lot of live mixing to stereo, I had an oscilloscope mounted where I could see it, and had it connected to the left and right mix buses, pre-fader, so if something came up out of phase, I could see it. But usually I could hear it before I looked at the 'scope. Sound Forge, which I use for editing, has a similar phase meter, but the default is with it rotated 45 degrees so that with the left and right channels in phase, you get a vertical line. Or maybe it's a horizontal line. I don't remember, but I found it confusing. -- For a good time, visit http://mikeriversaudio.wordpress.com |
#51
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MS Proximity Problem
, "Gary Eickmeier" wrote:
My main question about MS has always been, how do you know how much gain to put in the S channel to make it perfectly decode to XY as if it was recorded with two cardioids at 90 degrees? With theoretically perfect mic polar patterns, an XY array of cardioids at 90° is obtainable by sum & diff. matrixing of an MS pair, provided that: 1. the M mic is a subcardioid of polar pattern "V = 0.745 + 0.255.cos.theta", and at the same time: 2. The M channel is boosted by +11.87dB relative to that of the Fig8 S. (assuming equal mic sensitivities) Is your AT-2050 multi pattern mic capable of having its M mic configured with a pattern closely approaching the above-mentioned subcardioid value? But bear in mind that a two channel playback of an array of cardioid XY at 90° (having a large SRA) will generally give an unsatisfying, too-narrow soundstage in typical orchestra-recording situations. I am thiniking that my surround sound success may be due to the mike patterns between my M and S not having much overlap. I am using the AT-2050 multi-pattern large diaphragm cylindrical shaped mikes, the M set to cardioid and the S to Figure 8. It would probably be a different story if I set the M to omni. I think I don't want to set the M to Figure 8 because then the rear channels would be a reversal - mathematically, the Left channel would be composed (or comprised) of -M + (-S) and the right of -M + S. Something like that. Anyway, it has the effect of reversing the right and left channels, compared to the front. I have tried it. Your insistence on running everything through a surround system makes the entire analysis mind-bogglingly complex. Our heads are beginning to hurt. :-) And as for terminology, you referred somewhere in the thread to "spaciousness" being a strength of MS. Rather, the strength of MS or Blumlein, in the expected two speaker playback, is the pinpoint accuracy and "shear sense of rightness" of the stereo imaging. On occasion this can make the hairs stand up on the back of one's neck. Indeed, the detractors of MS or Blumlein will usually blame it on their very absence of "spaciousness", since the spaciousness that they enjoy is derived from the pleasant, enveloping, uncorrelated signals that are more abundant in spaced mic techniques. |
#52
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MS Proximity Problem
On 18/12/2015 11:42 a.m., Tom McCreadie wrote:
, Your insistence on running everything through a surround system makes the entire analysis mind-bogglingly complex. Our heads are beginning to hurt. :-) And as for terminology, you referred somewhere in the thread to "spaciousness" being a strength of MS. And there is no 'surround' info inherent in the MS stereo decoding. That is an artificial effect created by your panning and maybe some 5.1 encoder trickery. I think you are wanting one answer to two only semi-related subjects. Or I'm missing something... geoff |
#53
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MS Proximity Problem
So the OPs original problem was that "something changed" during the recording.
I'll ask this again... I didn't see an answer before but i may have missed it.... Was there __ANY___ kind of AGC turned on during the recording? Mark |
#54
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MS Proximity Problem
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#55
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MS Proximity Problem
wrote:
So the OPs original problem was that "something changed" during the recording. And it was likely position of the mikes. I'll ask this again... I didn't see an answer before but i may have missed it.... Was there __ANY___ kind of AGC turned on during the recording? He says no. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
#56
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MS Proximity Problem
On Friday, December 18, 2015 at 11:42:21 AM UTC-5, Scott Dorsey wrote:
wrote: So the OPs original problem was that "something changed" during the recording. And it was likely position of the mikes. I'll ask this again... I didn't see an answer before but i may have missed it.... Was there __ANY___ kind of AGC turned on during the recording? He says no. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." ok, happy holidays |
#57
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MS Proximity Problem
On Friday, December 18, 2015 at 2:04:05 PM UTC-5, wrote:
On Friday, December 18, 2015 at 11:42:21 AM UTC-5, Scott Dorsey wrote: wrote: So the OPs original problem was that "something changed" during the recording. And it was likely position of the mikes. I'll ask this again... I didn't see an answer before but i may have missed it.... Was there __ANY___ kind of AGC turned on during the recording? He says no. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." ok, happy holidays Merry Christmas!!! Jack |
#58
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MS Proximity Problem
On Thursday, December 17, 2015 at 10:02:15 AM UTC-7, Mike Rivers wrote:
On 12/17/2015 10:28 AM, Gary Eickmeier wrote: MS sterile? You must not be listening to the result in surround. I have found that MS makes an incredible surround encoder. The out of phase stuff goes way over to the sides and rear if you listen in DPL-II on a well balanced system.k I don't know what "listen in DPL-II" means (Dolby Pro Logic, maybe?), but I can tell you that the M-S mic setup was never intended to be any sort of a surround encoder. If you're using it for that purpose, you're on your own. Honestly, I doubt that you'll get nothing but arguments and diversions from this newsgroup. I think I must be mixing in too much S, and I can get some extreme L or R instruments decoding to the rear, but by and large I am getting a great surround that can amazingly decode to the sides, like all of the textbooks say can't be done. Well I'm sorry, I am doing it! Can you describe your signal path? Where are you getting the signal that drives the rear speakers? If this is the DPL-II decoder of which you speak, perhaps a button you press on a receiver? Surround decoders are designed to take in conventional left/right stereo and derive side and rear channels from it. If it's designed to take left and right and you're feeding it mid and side, or even left and right with a hole in the middle, then what you'll get out of it is bound to be goofy. Are you converting your mid and side channels to left and right with your computer, and then running those through a surround encoder to get your rear channels? Do they sound like good stereo when you just listen to the left and right derived from your mid and side recording? My main question about MS has always been, how do you know how much gain to put in the S channel to make it perfectly decode to XY as if it was recorded with two cardioids at 90 degrees? Just by listening? That's the best way. Equal parts is always too much side. Generally the side 3 dB lower than the mid is a good place to start. This is what's used as "normal" when you have a hardware M-S decoder or a stereo mic that has mid and side pickup but spits out left and right. But since the audio content of the side channel is substantially different from the mid channel, you can't reliably go by the numbers or meter readings. As I suggested before, start with no side channel and then bring it up symmetrically (+S and -S added equally to the mid channel) until it sounds right. What should the Lissajeaous pattern look like? Like any other stereo mic setup - scrambled eggs. However, when you have too much side (or not enough mid), you'll see it tilt toward the left I am thiniking that my surround sound success may be due to the mike patterns between my M and S not having much overlap. I am using the AT-2050 multi-pattern large diaphragm cylindrical shaped mikes, the M set to cardioid and the S to Figure 8. It would probably be a different story if I set the M to omni. I think I don't want to set the M to Figure 8 Those are both configurations that have been used. The arithmetic works out for all of them, it's just that the results will be different. But by using an omni or a bi-directional mic for the mid signal, you'll get more sound from the back of the room - just the way looks like it would work when you look at the polar diagrams. Sometimes that's helpful, sometimes it isn't. If you're going into a real surround decoder, it might be useful to feed it some real rear sound and hope it can figure out how to use it. I think it's a good thing that you're experimenting, but since nobody here seems to be doing what you're doing, it's hard to be really helpful. -- For a good time, visit http://mikeriversaudio.wordpress.com I used to have a system that I experimented with "surround" sound on. I did it entirely post amplifier. I hooked a small set of speakers in series that I used for the "rears" and took the signal from the + of the left channel of the amplifer and the + of the right channel of the amp. The result was the signal that was not common to either channel. I used an "L" pad to bring down the volume on the "rear surround" speakers. At that time one of the microphone array patterns that I was experimenting with was Blumlein. That really lit up those rear speakers. What I did not care for with Blumlein was that I had to keep the ensemble being recorded within a 90 degree arc and that the rear signal was reversed compared to the front. The sides got really interesting especially if a choir was walking up the side of the performance hall to the stage. On playback , they moved across the middle. Depending on the ensemble, I may use ORTF, or a spaced pair of Super cardiods at 103 degrees. If I use MS I use a set of flanking microphones. for additional ambience and depth. When the hall is very good, I use a Jecklin disc with omnis. |
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MS Proximity Problem
Richard Kuschel wrote:
I used to have a system that I experimented with "surround" sound on. I did it entirely post amplifier. I hooked a small set of speakers in series that I used for the "rears" and took the signal from the + of the left channel of the amplifer and the + of the right channel of the amp. The result was the signal that was not common to either channel. I used an "L" pad to bring down the volume on the "rear surround" speakers. At that time one of the microphone array patterns that I was experimenting with was Blumlein. That really lit up those rear speakers. What I did not care for with Blumlein was that I had to keep the ensemble being recorded within a 90 degree arc and that the rear signal was reversed compared to the front. The sides got really interesting especially if a choir was walking up the side of the performance hall to the stage. On playback , they moved across the middle. Depending on the ensemble, I may use ORTF, or a spaced pair of Super cardiods at 103 degrees. If I use MS I use a set of flanking microphones. for additional ambience and depth. When the hall is very good, I use a Jecklin disc with omnis. Thanks Richard, might have to try some of those! Gary |
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MS Proximity Problem
"Richard Kuschel" wrote in message
news:7c1b98e9-8b34-431e-9963- I hooked a small set of speakers in series that I used for the "rears" and took the signal from the + of the left channel of the amplifer and the + of the right channel of the amp. The result was the signal that was not common to either channel. I used an "L" pad to bring down the volume on the "rear surround" speakers. At that time one of the microphone array patterns that I was experimenting with was Blumlein. That really lit up those rear speakers. What I did not care for with Blumlein was that I had to keep the ensemble being recorded within a 90 degree arc and that the rear signal was reversed compared to the front. If the rear speakers were in series, in what sense was the rear signal reversed? Any difference between the rear speakers would be caused by impedance differences between the speakers, not the signals, wouldn't it? |
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MS Proximity Problem
"Mike Rivers" wrote in message
... I don't know what "listen in DPL-II" means (Dolby Pro Logic, maybe?), but I can tell you that the M-S mic setup was never intended to be any sort of a surround encoder. If you're using it for that purpose, you're on your own. Honestly, I doubt that you'll get nothing but arguments and diversions from this newsgroup. Although the engineers at Dolby Labs were always quite tight-lipped about the intellectual property details, they did tell me more than once that Dolby Pro Logic was designed to produce a "pleasing surround effect" when fed a stereo signal containing no encoded surround signal. This was apparently a fairly important design consideration. |
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MS Proximity Problem
None wrote:
If the rear speakers were in series, in what sense was the rear signal reversed? Any difference between the rear speakers would be caused by impedance differences between the speakers, not the signals, wouldn't it? Dynaquad.... both amplifiers have a common ground, and so if you bridge a load _between_ the two channel outputs, what you get is the difference signal between the two channels. The rear speakers are in series with one another, bridged across the output with no path to ground. You can thank David Hafler for the idea. It was... well, to be honest I think it was kind of cheesy... --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
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MS Proximity Problem
None wrote:
"Mike Rivers" wrote in message ... I don't know what "listen in DPL-II" means (Dolby Pro Logic, maybe?), but I can tell you that the M-S mic setup was never intended to be any sort of a surround encoder. If you're using it for that purpose, you're on your own. Honestly, I doubt that you'll get nothing but arguments and diversions from this newsgroup. Although the engineers at Dolby Labs were always quite tight-lipped about the intellectual property details, they did tell me more than once that Dolby Pro Logic was designed to produce a "pleasing surround effect" when fed a stereo signal containing no encoded surround signal. This was apparently a fairly important design consideration. The original Dolby Stereo did so, but when the steering logic was added with the Dolby Pro-Logic system, the resulting weird shifts in perspective on the front speakers made the effect much less than pleasing. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
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MS Proximity Problem
Scott Dorsey wrote:
None wrote: "Mike Rivers" wrote in message ... I don't know what "listen in DPL-II" means (Dolby Pro Logic, maybe?), but I can tell you that the M-S mic setup was never intended to be any sort of a surround encoder. If you're using it for that purpose, you're on your own. Honestly, I doubt that you'll get nothing but arguments and diversions from this newsgroup. Although the engineers at Dolby Labs were always quite tight-lipped about the intellectual property details, they did tell me more than once that Dolby Pro Logic was designed to produce a "pleasing surround effect" when fed a stereo signal containing no encoded surround signal. This was apparently a fairly important design consideration. The original Dolby Stereo did so, but when the steering logic was added with the Dolby Pro-Logic system, the resulting weird shifts in perspective on the front speakers made the effect much less than pleasing. --scott Well, this is the reason I am reporting that a good MS recording can be a great encoded surround signal if you balance the M and S just right. I have demonstrated it many times to myself on my surround system, the Lissajeous pattern corroborates it, and it seems logical if you examine the signal. One pure example is as mentioned before the channel check and phase check of a test record. The announcer says "in phase" and then "out of phase." On my system, the out of phase announcement comes from the back of the room, because the DPL decoder sends the out of phase info there. I also get some sounds coming (correctly) from the sides, which has always been said is not possible (summing localization between the left front and left rear). In my last session during the encore number a woman pushing a wheelchair had to get by me. She shouted from my left, "Can we get through here?" and that is where it comes from on playback - the right side wall. During one number the audience starts singing along, quietly at first, then louder. It is a chilling thrill to hear them coming from all around me. The DPL decoder may not do much except a "pleasing effect" when fed a standard, in phase signal, but it certainly can decode matrix surround quite well, and some MS recordings seem to be already surround encoded and there are no weird shifts in perspective in the front channels. It works, is stereo compatible, and it's free! Gary Eickmeier |
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MS Proximity Problem
Gary Eickmeier wrote:
The DPL decoder may not do much except a "pleasing effect" when fed a standard, in phase signal, but it certainly can decode matrix surround quite well, and some MS recordings seem to be already surround encoded and there are no weird shifts in perspective in the front channels. It works, is stereo compatible, and it's free! Yes, but it degrades the front imaging with the steering logic, and although what comes out of the rear channels may sound cool, it does not bear very much connection with what you're hearing behind you in the hall. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
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MS Proximity Problem
Although the engineers at Dolby Labs were always quite tight-lipped about the intellectual property details, they did tell me more than once that Dolby Pro Logic was designed to produce a "pleasing surround effect" when fed a stereo signal containing no encoded surround signal. This was apparently a fairly important design consideration. The original Dolby Stereo did so, but when the steering logic was added with the Dolby Pro-Logic system, the resulting weird shifts in perspective on the front speakers made the effect much less than pleasing. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." I think the true genius of Dolby is that he took that simple idea of connecting rear speakers across L and R and made a muti million busine$$ from it. Mark |
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MS Proximity Problem
On Monday, December 21, 2015 at 8:58:29 AM UTC-5, Scott Dorsey wrote:
Gary Eickmeier wrote: The DPL decoder may not do much except a "pleasing effect" when fed a standard, in phase signal, but it certainly can decode matrix surround quite well, and some MS recordings seem to be already surround encoded and there are no weird shifts in perspective in the front channels. It works, is stereo compatible, and it's free! Yes, but it degrades the front imaging with the steering logic, and although what comes out of the rear channels may sound cool, it does not bear very much connection with what you're hearing behind you in the hall. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." Awww now you ruined it for everyone... Don't tell them about Santa. |
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MS Proximity Problem
On 21-12-2015 04:49, Gary Eickmeier wrote:
Scott Dorsey wrote: None wrote: "Mike Rivers" wrote in message ... I don't know what "listen in DPL-II" means (Dolby Pro Logic, maybe?), but I can tell you that the M-S mic setup was never intended to be any sort of a surround encoder. If you're using it for that purpose, you're on your own. Honestly, I doubt that you'll get nothing but arguments and diversions from this newsgroup. Although the engineers at Dolby Labs were always quite tight-lipped about the intellectual property details, they did tell me more than once that Dolby Pro Logic was designed to produce a "pleasing surround effect" when fed a stereo signal containing no encoded surround signal. This was apparently a fairly important design consideration. The original Dolby Stereo did so, but when the steering logic was added with the Dolby Pro-Logic system, the resulting weird shifts in perspective on the front speakers made the effect much less than pleasing. --scott Yes. If you have a proper stereo recording the spatial depth - in front of the line between the loudspeakers as well as behind it - will be less, not more, with pro-logic playback, omni-pairs fare especially ill. Well, this is the reason I am reporting that a good MS recording can be a great encoded surround signal if you balance the M and S just right. Yes. With your interest, your mumber of microphones and recorder, I fail to comprehend why you are not making real discrete quad recordings. Forget about 5.1, except that you can in fact remap them to 5.1 with your audition if I recall its capabilities right. When you get those right, nobody notices that it is anything but really really really good stereo, wauw!, until you turn the rear channels off. The DPL decoder may not do much except a "pleasing effect" when fed a standard, in phase signal, but it certainly can decode matrix surround quite well, and some MS recordings seem to be already surround encoded and there are no weird shifts in perspective in the front channels. It works, is stereo compatible, and it's free! The dpl decoder thing is like replacing real whipped cream with the stuff that you do not want to know now is made but sold on spray cans to decorate cakes with. Gary Eickmeier Kind regards Peter Larsen |
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MS Proximity Problem
Peter Larsen wrote:
Yes. With your interest, your mumber of microphones and recorder, I fail to comprehend why you are not making real discrete quad recordings. Forget about 5.1, except that you can in fact remap them to 5.1 with your audition if I recall its capabilities right. When you get those right, nobody notices that it is anything but really really really good stereo, wauw!, until you turn the rear channels off. I have made discrete surround recordings, using a DTS encoder that I found online. I haven't had any luck with the Dolby Digital 5.1 mixer that is in Audition. I have a 5.1 computer speaker kit as well, and I am supposed to be able to make the sound come out of all of these speakers, but so far haven't had much luck. Probably something simple. But as for the DTS discrete recordings, the surround channels seem more "disconnected" from the front ones, or should I say the sound scene that I am trying to convey. Anyway, in my amateur recording venues, it would be a lot more difficult to set up 4 mikes on stands without bothering the audience and the powers that be. Biggest question: Should I place the rear mikes right with the front set, or should I move them back further into the audience? Might be able to get away with it if I use some tiny lapel type mikes and skinny posts stretched up as high as I can get them, then run some thin wires up to the recorder and tape them down. Agh.... Gary |
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MS Proximity Problem
On 22-12-2015 03:00, Gary Eickmeier wrote:
Peter Larsen wrote: Yes. With your interest, your mumber of microphones and recorder, I fail to comprehend why you are not making real discrete quad recordings. Forget about 5.1, except that you can in fact remap them to 5.1 with your audition if I recall its capabilities right. When you get those right, nobody notices that it is anything but really really really good stereo, wauw!, until you turn the rear channels off. I have made discrete surround recordings, using a DTS encoder that I found online. I haven't had any luck with the Dolby Digital 5.1 mixer that is in Audition. I have a 5.1 computer speaker kit as well, and I am supposed to be able to make the sound come out of all of these speakers, but so far haven't had much luck. Probably something simple. No no no and no. Record 4 tracks, play 4 tracks back. No decoder. Discrete surround. But as for the DTS discrete recordings, the surround channels seem more "disconnected" from the front ones, or should I say the sound scene that I am trying to convey. Anyway, in my amateur recording venues, it would be a lot more difficult to set up 4 mikes on stands without bothering the audience and the powers that be. Keep DTS well out of it. Try a Brucks sputnik, it appears that you already have the hardware for it even if your mics are somewhat large. https://www.google.dk/search?q=Try+a...s+ sputnik%22 Or search for "Brucks sputnik". Jerry Bruck is/was a New York based recording engineer. Brucks Sputnik is a setup of 4 cardioids, easy to mimic with 3 stereo cross-bars from K&M using one as the "backbone" between front and rear pairs. The setup I used it for was a church event with some of if happening at or with the organ so I had to record a valid rear stereo image as well and I did not want to put a stand in the main audience pathway as doing that necessitates someone wielding the Elder Wand to keep the tide of the huns away from the stand. Biggest question: Should I place the rear mikes right with the front set, or should I move them back further into the audience? Note, I haven't actually done this, I have used a Brucks sputnik type setup once, but mixed it to stereo. In that context I ended up delaying the rearwards aimed pair. For real quad playback ... hmm .... I dunno what would work ... anyway the classic advice is that ambience microphones for stereo should be "in the haas window", generally described as no more than 10 meters behind the main pair. Further back they become "echo microphones". IF you map it (!) to 5.1 space it should be a remix because the angle asumptions are different for a setup with a center loudspeaker. Which is why a 5.1 mic setup - you should be able to find one illustrated on dpa's website - is done with 5 mics. I have heard real quad, and it is magnificent in terms of rendering the recorded space. In theory Audition can do it, and I think the ability to do so came with 2.0. Might be able to get away with it if I use some tiny lapel type mikes and skinny posts stretched up as high as I can get them, then run some thin wires up to the recorder and tape them down. Agh.... Up to the recorder ... ??? Gary Kind regards Peter Larsen |
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MS Proximity Problem
Scott Dorsey wrote: "- show quoted text -
The original Dolby Stereo did so, but when the steering logic was added with the Dolby Pro-Logic system, the resulting weird shifts in perspective on the front speakers made the effect much less than pleasing. - show quoted text -" Those "weird shifts" were a result of the source, not the Pro-Logic platform. I noticed it far more on VHS playback than with digital sources. But care must also be taken in the production stages to avoid as much unwanted phase issues as possible, so as to not "trick" Pro Logic or other matrix steering codecs with regards to itinerant placement(!) Of course, that advice might have been more critical back in the pre-discrete surround era. |
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MS Proximity Problem
I read it from several sources that "Top Gun" was
specifically produced to sound best on and take full advantage of the steering logic surround systems already in theaters and eventually making their way into homes. In fact, I found Top Gun to sound equally good in Pro Logic or x.1 surround. |
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MS Proximity Problem
On 12/21/2015 10:57 PM, Peter Larsen wrote:
No no no and no. Record 4 tracks, play 4 tracks back. No decoder. Discrete surround. For gosh sakes, folks, let him play with his toys. If he's getting something that he likes, fine. With some experience in recording - rather than plugging things together to get his perception of "surround" - he'll learn to recognize when something isn't right with the setup and will get more consistent results. Unless, of course, the results that he's getting are random and more work for him than don't. -- For a good time, visit http://mikeriversaudio.wordpress.com |
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MS Proximity Problem
Peter Larsen wrote: "No no no and no. Record 4 tracks, play 4 tracks back. No decoder.
Discrete surround" Above = the ultimate goal. Dolby Digital and DTS are just that - discrete. The former just happens to do it in the lossy realm. |
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MS Proximity Problem
Mike Rivers wrote:
On 12/21/2015 10:57 PM, Peter Larsen wrote: No no no and no. Record 4 tracks, play 4 tracks back. No decoder. Discrete surround. For gosh sakes, folks, let him play with his toys. If he's getting something that he likes, fine. With some experience in recording - rather than plugging things together to get his perception of "surround" - he'll learn to recognize when something isn't right with the setup and will get more consistent results. Unless, of course, the results that he's getting are random and more work for him than don't. Well, my equipment is no more nor less "toys" than is Frank's, or yours, or Ty Ford's, who goes to all the shows to see what "toys" have come out of interest. I have my experimenting, because I am an eager learner of all kinds of recording, and I have my serious work for the concert band or my video work, which has to be correct for the clients. I believe I know what I am getting and can recognize what works and what doesn't, which is the reason for this thread. I am not flailing about at random and not understanding what I am doing or getting. It's a learning process for me, just like it is for you. I think it is well known how to get good frontal stereo sound. You set that up and then you know you have got some good stuff for the client, but then you can also "take a shot" at some more involved techniques and use it or not afterwards. Gary |
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MS Proximity Problem
wrote:
Scott Dorsey wrote: "- show quoted text - The original Dolby Stereo did so, but when the steering logic was added with the Dolby Pro-Logic system, the resulting weird shifts in perspective on the front speakers made the effect much less than pleasing. - show quoted text -" Those "weird shifts" were a result of the source, not the Pro-Logic platform. I noticed it far more on VHS playback than with digital sources. But care must also be taken in the production stages to avoid as much unwanted phase issues as possible, so as to not "trick" Pro Logic or other matrix steering codecs with regards to itinerant placement(!) The purpose of the steering logic is to always keep the dominant midrange source centered on the stereo image. This is fine for movies where you can mix them so that the dialogue is in the center all the time. It's not so good for musical recordings where they have to be mixed in a very specific way in order to keep the steering logic from changing the gains and moving the soundstage from side to side to center that loud sax or whatever. Normal Dolby Stereo will not do this. Pro-Logic basically exists for consumer videotape systems, to compensate for alignment and level mismatches. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
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MS Proximity Problem
Peter -
I didn't have much luck with the link to the Sputnik, but I have already tried my version of four cardioids, which I call the Four Leaf Clover. Mine are pointing N, E, S, and W. I am recording discrete channels but mixing to surround by taking the three front mikes - well, one front and two side facing - and using them for the front sound, and then the rear mike can be incorporated for the surround. I forget exactly how I mixed that in, might have split it into two channels and inverted one of them in a certain way. Probably should just aim them like two pairs of XY systems. In any case, my DTS surround is a discrete system and does use only four channels, not 5.1. If there is a singer in the mix, she would obviously be mixed into the front channels in the usual way but the speakers would be sent a discrete surround and there would be no separate center channel. Something like that.... Gary Peter Larsen wrote: On 22-12-2015 03:00, Gary Eickmeier wrote: Peter Larsen wrote: Yes. With your interest, your mumber of microphones and recorder, I fail to comprehend why you are not making real discrete quad recordings. Forget about 5.1, except that you can in fact remap them to 5.1 with your audition if I recall its capabilities right. When you get those right, nobody notices that it is anything but really really really good stereo, wauw!, until you turn the rear channels off. I have made discrete surround recordings, using a DTS encoder that I found online. I haven't had any luck with the Dolby Digital 5.1 mixer that is in Audition. I have a 5.1 computer speaker kit as well, and I am supposed to be able to make the sound come out of all of these speakers, but so far haven't had much luck. Probably something simple. No no no and no. Record 4 tracks, play 4 tracks back. No decoder. Discrete surround. But as for the DTS discrete recordings, the surround channels seem more "disconnected" from the front ones, or should I say the sound scene that I am trying to convey. Anyway, in my amateur recording venues, it would be a lot more difficult to set up 4 mikes on stands without bothering the audience and the powers that be. Keep DTS well out of it. Try a Brucks sputnik, it appears that you already have the hardware for it even if your mics are somewhat large. https://www.google.dk/search?q=Try+a...s+ sputnik%22 Or search for "Brucks sputnik". Jerry Bruck is/was a New York based recording engineer. Brucks Sputnik is a setup of 4 cardioids, easy to mimic with 3 stereo cross-bars from K&M using one as the "backbone" between front and rear pairs. The setup I used it for was a church event with some of if happening at or with the organ so I had to record a valid rear stereo image as well and I did not want to put a stand in the main audience pathway as doing that necessitates someone wielding the Elder Wand to keep the tide of the huns away from the stand. Biggest question: Should I place the rear mikes right with the front set, or should I move them back further into the audience? Note, I haven't actually done this, I have used a Brucks sputnik type setup once, but mixed it to stereo. In that context I ended up delaying the rearwards aimed pair. For real quad playback ... hmm .... I dunno what would work ... anyway the classic advice is that ambience microphones for stereo should be "in the haas window", generally described as no more than 10 meters behind the main pair. Further back they become "echo microphones". IF you map it (!) to 5.1 space it should be a remix because the angle asumptions are different for a setup with a center loudspeaker. Which is why a 5.1 mic setup - you should be able to find one illustrated on dpa's website - is done with 5 mics. I have heard real quad, and it is magnificent in terms of rendering the recorded space. In theory Audition can do it, and I think the ability to do so came with 2.0. Might be able to get away with it if I use some tiny lapel type mikes and skinny posts stretched up as high as I can get them, then run some thin wires up to the recorder and tape them down. Agh.... Up to the recorder ... ??? Gary Kind regards Peter Larsen |
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MS Proximity Problem
Scott Dorsey wrote: "Normal Dolby Stereo will not do this. Pro-Logic basically exists for consumer
videotape systems, to compensate for alignment and level mismatches. " Pro-Logic IS the home version of Dolby Stereo(cinema- employed). Dolby Stereo(and other matrix-encode surround formats) were DESIGNED and implemented with a center in mind even before Jaws and A New Hope were still in shooting. Typical large, wiiiide, cinema auditoriums made a center array a mandatory part of any multi-channel presentation, matrix or discrete. This was known before WW2. The only real differences between DS and DPL are the number of speakers employed, and more per-channel processing(EQ, delay, etc) than exist in the home version. So while you are correct in your assessment of consumer tape-based video playback systems, I can never accept that the domestic adaptation of Dolby Stereo(Pro Logic)was implemented solely to account for such inconsistencies. My main movie listening system is still Pro Logic. Why? Because most newer home theater receivers have gone HDMI on their rear panels. I still have a suite of perfectly functional analog, RCA-out components that would not have a home on the back of anything manufactured in the last ten years. Do I appreciate the sonic advantages of Dolby Digital and DTS? Certainly. But quality of source material matters far more to me than number of discrete surround channels I can employ with such a newer format. |
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MS Proximity Problem
wrote:
Pro-Logic IS the home version of Dolby Stereo(cinema- employed). Dolby Stereo(and other matrix-encode surround formats) were DESIGNED and implemented with a center in mind even before Jaws and A New Hope were still in shooting. Typical large, wiiiide, cinema auditoriums made a center array a mandatory part of any multi-channel presentation, matrix or discrete. This was known before WW2. The only real differences between DS and DPL are the number of speakers employed, and more per-channel processing(EQ, delay, etc) than exist in the home version. Pro-Logic is the conventional Dolby Stereo with steering logic added in front of the matrix. So while you are correct in your assessment of consumer tape-based video playback systems, I can never accept that the domestic adaptation of Dolby Stereo(Pro Logic)was implemented solely to account for such inconsistencies. There were several home Dolby Stereo systems including the once-ubiquitous Shure decoder. The Pro-Logic system was designed specifically to overcome problems that people had using Dolby Stereo in a home environment. If you do not believe me, please read the documentation. My main movie listening system is still Pro Logic. Why? Because most newer home theater receivers have gone HDMI on their rear panels. I still have a suite of perfectly functional analog, RCA-out components that would not have a home on the back of anything manufactured in the last ten years. Do I appreciate the sonic advantages of Dolby Digital and DTS? Certainly. But quality of source material matters far more to me than number of discrete surround channels I can employ with such a newer format. That's nice but has nothing to do with the subject. Please do not attempt to change the subject. --scott -- "C'est un Nagra. C'est suisse, et tres, tres precis." |
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