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Offline rocksuitcase

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Re: Oddball microphone techniques
« Reply #210 on: April 18, 2016, 02:24:58 PM »
Thank you very much GB! You understand the concept to which I was eluding.
I messed around a bit with it. I flipped the wrong channel polarity; left channel flipped, not right. 
Also, I don't think that I have an MS decoder available in the editing programs that I have (Audacity, Sound Studios, Reaper).
I've got some homework to do in tracking down an MS decoder ring. So I will try to mess with it a bit later.
kindms found a video on youtube he references every time he does the MS decode. I bat signaled him and hopefully he can post it downthread.   :turnevil:
music IS love

When you get confused, listen to the music play!

Mics:         AKG461/CK8|Beyer M 201E
Recorders:Marantz PMD661 OADE Concert mod; Tascam DR680 MKI

Offline Gutbucket

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Re: Oddball microphone techniques
« Reply #211 on: April 18, 2016, 03:10:40 PM »
Volt, I believe MBHO also makes a single diaphragm figure 8 SDC, and the newer version of the Emesser uses the MBHO 8.

The Naiant X-8S figure-8 I'm using for these recent experiments consists of two back to back cardioid SDCs mounted in a single housing.  The 'back' one is phase inverted and they are then summed together in the mic body prior to the signal leaving the mic.  By design, the two cardioid capsules must be very well matched and level adjusted to achieve a decent null and produce a good figure 8 pattern.  They can never be as fully coincident as a single diaphragm figure-8 so I suppose pattern might suffer at very high frequencies, but that's probably too high to matter for M/S purposes.

In terms of what is happening when producing a figure-8 response by summing two back to back carioids with one out of polarity with the other, begin by considering the essential essence of the cardioid pattern as being the equal sum of omni plus 8.  For sounds arriving from directly ahead, both the omni and the 8 component signals are equal and in polarity with each other, for sound from directly behind, both are equal in level yet opposite in polarity, and cancel each other out (producing the rear-facing cardioid null point), and so on around the circle.

We can invert the polarity of an 8 by pointing it the opposite direction, but the polarity of an omni doesn't change regardless of the direction it points. When two cardioids are placed back to back and summed with the polarity flipped on one of them to form a virtual figure 8 pattern, the two omni components have opposite polarity and cancel each other out entirely, but two figure 8 components have the same polarity and reinforce each other and the result is a single figure 8.

In poor form algebra.. (fig 8 + omni)     +         (-        (-fig 8 + omni))                      =    2x(fig 8 )
                                             ^               ^          ^                  ^                                             ^
                                         cardioid   |    sum  |  invert | opposite pointed cardioid)      |     figure 8




Tonal match between Mid and Side channels isn't critical like it is between Left and Right channels, although the overall combined tonal output of the M/S pair is just as important as a L/R pair.  The tone of the Side signal primarily determines "where the stereoness happens" in the resulting L/R output.  Primarily, variation in the frequency response of the Side channel is going to effect which frequency ranges are more stereoized and which frequency ranges are more monoized.   In Mike's oddball M/S setup using invert-summed baffled omnis for the Side signal, the Side signal will consist of mostly high-frequency information and will not be tonally matched at all with the Mid channel.  The L/R output will be stereoized up top and monoized down low.  It will also be slightly brighter since the the side signal is only adding energy to the resulting overall mix at high frequencies.

Lets assume a flat L/R response is desirable, and we have a flat output from our Mid microphone.  The tonal variation of the Side channel IS going to effect the tonal balance of the resulting recording somewhat, depending on how much is used, as well as affecting which frequency ranges are more stereo and which are more mono, yet in a way which is symmetrical between the Left and Right sides.  So a tonal mis-match between Mid and Side effects "stereoness by frequency" and the tonal distribution from the center out to the sides across the stereo image.  But things won't sound lopsided if the tonal balance between Mid & Side differs greatly.
« Last Edit: April 18, 2016, 03:39:34 PM by Gutbucket »
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Offline kindms

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Re: Oddball microphone techniques
« Reply #212 on: April 18, 2016, 03:12:38 PM »
Thank you very much GB! You understand the concept to which I was eluding.
I messed around a bit with it. I flipped the wrong channel polarity; left channel flipped, not right. 
Also, I don't think that I have an MS decoder available in the editing programs that I have (Audacity, Sound Studios, Reaper).
I've got some homework to do in tracking down an MS decoder ring. So I will try to mess with it a bit later.
kindms found a video on youtube he references every time he does the MS decode. I bat signaled him and hopefully he can post it downthread.   :turnevil:

I have this youtube video bookmarked as I seem to need to refer to it all the damn time.

https://www.youtube.com/watch?v=eVOBRx7zGzw

AKG414 XLS/ST> TCM-Mod Tascam HDP2
Musichall Mambo > VR-2's

Offline Gutbucket

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Re: Oddball microphone techniques
« Reply #213 on: April 18, 2016, 04:30:10 PM »
Thanks for the input Jon..  both the microphone and this thread.
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Offline kindms

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Re: Oddball microphone techniques
« Reply #214 on: July 04, 2016, 09:06:35 AM »
http://taperssection.com/index.php?topic=178302.0

We ran spilt omnis from the lawn with the forward and rear facing cards from the Lawn at SPAC night 1. It rained pretty hard prior so we kept it "low key" for night 1 LOL. I did a quick mix with all 4 channels. I think it came out pretty good.

Night 2 we ran spilt ck22s again this time opting for AKG414 coincident blumlein fig8s in the center as well as a AKGck8 short shotgun and a rear facing ck61

I was not at night 3 last night but was told 10foot spilts with center mic stand 414s mid side etc. Should be interesting
AKG414 XLS/ST> TCM-Mod Tascam HDP2
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Offline rocksuitcase

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Re: Oddball microphone techniques
« Reply #215 on: July 04, 2016, 11:41:06 AM »
http://taperssection.com/index.php?topic=178302.0

We ran spilt omnis from the lawn with the forward and rear facing cards from the Lawn at SPAC night 1. It rained pretty hard prior so we kept it "low key" for night 1 LOL. I did a quick mix with all 4 channels. I think it came out pretty good.

Night 2 we ran spilt ck22s again this time opting for AKG414 coincident blumlein fig8s in the center as well as a AKGck8 short shotgun and a rear facing ck61

I was not at night 3 last night but was told 10foot spilts with center mic stand 414s mid side etc. Should be interesting
I am planning to "fill in" this thread with the pics and ideas we tried from Dead & Co, as well as the three phish shows.
Last night, 7-03. we ran 10 foot Omni split with a Ck61 card in center plus 414's in MidSide with the Mid being a forward facing fig 8.
Ed, airbladder, ran his Neumann TL's on the Omni stands and also Neumann short shotguns in the center plus pair of small crossed cards.
Pictures coming up later.
music IS love

When you get confused, listen to the music play!

Mics:         AKG461/CK8|Beyer M 201E
Recorders:Marantz PMD661 OADE Concert mod; Tascam DR680 MKI

Offline Gutbucket

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Re: Oddball microphone techniques
« Reply #216 on: July 11, 2016, 12:10:50 PM »
Thanks for the updates and recordings, Mr. rock'case.  I've been mostly off line for the past week and need to catch up with some listening.  I did pull your Phish recording and as I usually do, made EQ and surround upmix parameter adjustments to slip a toe through the door which defines an invisible psychological threshold my brain needs to cross before I can consciously ignore all the technical aspects of a recording and simply experience an auditory "like there" experience as a lover of music rather than as recordist/technician.  To me that's the acid test of any live recording - Not how the raw recording sounds, but rather if it allows for those kinds of manipulations necessary to help that mental magic trick work convincingly.  The adjustments most appropriate for me in this particular situation may not be the same for everyone or every playback situation, and most likely aren't.  The more important thing is that the recording has within it the capability for that kind of transportive experience.

I should really get to work on posting some of my recordings made using these oddball techniques here for you all to listen to and play around with.  Posting samples of both the individual multichannel elements along with a few different stereo mix variants made from them.  I'm hoping that will help illustrate how there can be several vastly different subjective mix options for any one recording made using these techniques, each viable on it's own terms.  Some listeners will tend to lean towards one presentation over another, while others may find all of them equally enjoyable, if for different reasons.  Listeners interested in diving deeper, playing around with fine-tuning the mix relationships themselves to find what subjectively works best for them versus what doesn't, can mess around with recombining the individual parts in various ways. That these multi-mic techniques give us so many equally viable alternate options is one of the big attractions of these approaches for me, with the flip-side being the burden of having to choose one over the other.
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Offline rocksuitcase

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Re: Oddball microphone techniques
« Reply #217 on: July 11, 2016, 01:08:22 PM »
I was thinking about something similar concerning posting the raw files so you could check them out and play around to see what type of mix you (or any of us) come up with.
so far, only one of our Phish shows has been posted. we have 7-03 ready to up. and 7-02 should be up after that. For now, I will post the Rig pic links and the DnCo plus Phish night one recording links in this thread:
Rig pic links:
http://taperssection.com/index.php?topic=178302.0
http://taperssection.com/index.php?topic=178319.msg2193613#msg2193613
http://taperssection.com/index.php?topic=178320.0
http://taperssection.com/index.php?topic=178321.0

http://taperssection.com/index.php?topic=178139.0
https://archive.org/details/dnCo2016-06-21.DnCo2016-06-21.OmniHyper24

music IS love

When you get confused, listen to the music play!

Mics:         AKG461/CK8|Beyer M 201E
Recorders:Marantz PMD661 OADE Concert mod; Tascam DR680 MKI

Offline rocksuitcase

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Re: Oddball microphone techniques
« Reply #218 on: August 19, 2016, 10:10:52 PM »
Here are the first results from Greyfox. 2 sets which are on LMA.
https://archive.org/details/delmccoury2016-07-15.24.ck22ck8ck61
This one is:
ch 1&2: AKG ck22 Omni spread 100 cm
ch 5&6: AKG ck8 shotgun fwd 0'|AKG ck61 naiant active cardiod rear 180' ->
Tascam DR680|SD 24/48
Transfer: SD|Dell Latitude E5530-> Audacity
CDwav-> TLH (flac level 8)
Mixing notes:
CH1&2=AKG ck22 Omni spread 100 cm -3dB
ch3  =AKGck8 fwd 0'               -7dB
ch4  =AKGck61 rear 180'           -9dB
Equalization applied-(<4dB) bass reduction under 400 Hz.

https://archive.org/details/steepcanyon2016-07-14.24.ck22ck414.flac
This one is:
ch 1&2: AKG ck22 Omni spread 36 cm
ch 3&4: AKG c414XLS/ST cardiod fwd 0'|AKG c414XLS/ST cardiod rear 180'
Tascam DR680|SD
Transfer: SD|Dell Latitude E5530-> Audacity
CDwav-> TLH (flac level 8)
Mixing notes:
CH1&2=AKG ck22 Omni spread 36 cm - 2dB
ch3  =AKGc414 fwd 0'            - 7dB
ch4  =AKGc414 rear 180'         -18dB
Equalization applied- bass reduction below 200Hz.

The 414's in the center definitely impart a smoothness which is not typically there with the ck8.
I include the mixing notes from the text file in this thread. Didn't put them in the main LMA page cause no one cares except us taper freaks.
We still need to upload Phish 2 & 3.
Please listen critically and comment in this thread (especially if you're not me, gut, or kindms, cause we'll be all over this thread!)
For photos of the Greyfox set ups:
http://taperssection.com/index.php?topic=178908.0
 

music IS love

When you get confused, listen to the music play!

Mics:         AKG461/CK8|Beyer M 201E
Recorders:Marantz PMD661 OADE Concert mod; Tascam DR680 MKI

Offline Gutbucket

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Re: Oddball microphone techniques
« Reply #219 on: June 27, 2017, 02:21:10 PM »
Big thanks those of you trying some of these ideas for yourselves.  Seems like using a center mic between spaced omnis is becoming more common around TS.  I'm happy to see that and hope it's working well for those trying it.

There is a good discussion on the relationship between a spaced pair of omnis and a center microphone is currently going on over here- Relationships between spaced omnis and center mic.  I didn't intend to totally commandeer that thread, yet took it as a good opportunity to sum up my thinking about spaced omnis in general and when and why the addition of a center mic may be advantageous.  My contribution there, which starts here, is in some ways a summary of much of what I've been pursuing and figuring out in this thread over the course of so many years.   I've more to post there, but am giving it a rest for a few days to see if others have comments.
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Offline Gutbucket

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Re: Oddball microphone techniques
« Reply #220 on: June 27, 2017, 03:36:07 PM »
Figure while I'm revisting this thread I'll post a few photos of my most recent outdoor variation on these themes, from the Wanee festival earlier this spring at the Spirit of the Swannee in Live Oak, FL. as I'd meant to post these here a few months back.

This year at Wanee I broke out my old hard Nerf-ball DIY APE's (Acoustic Pressure Equalizers as DPA calls them) which I was using years ago on my 4-omni rigs discussed at length earlier in this thread.  In these photos they are the round black balls on the far ends of the thin telescopic antennas and have hemispheric foam windscreens pinned to them.  The omnis are flush to the ball surface under the apex of the foam hemispheres.   Years ago, I originally used those to give the omnis a bit more forward directionality, focus and a presence range boost, partly to help compensate for less spacing than I would have preferred.  This time I have sufficient spacing between the omnis (5' instead of 3') and get all the focus and presence I need from the four near-spaced 4098 supercardioids pointing forward, left, right, and backwards.  I now use the left and right facing supercards as the primary Left and Right channels.  The wide spaced omnis still provide all important deep bass extension and stereo bass information to the Left and Right main channels, which are qualities unaffected by the sphere attachments.

The intention of using the APE spheres this time is to give the omnis some rearward directionality preference and presence above the bass range, reducing their sensitivity in the mids and highs slightly with respect to pickup of direct sound from in front.  That's because, outside of the bass range, I'm now mostly using the omnis for ambience in a 2-channel mix, and as dedicated surround channels for surround playback.  A bit less direct sound pickup pickup from in front allows me to use more ambience / surround level.  The APEs are probably not giving me the 6-10 dB reduced sensitivity towards the front which I figure would be optimal, but it was easy to implement with what I had on hand.  If wondering about their angle in the photo, made apparent by the hemispheric windsceens, their primary rearward axis actually face about 135 degrees and 225 degrees away from the front, which aligns their minimum sensitivity point with dead-ahead since the polars for spherical APEs show a small rear lobe.  Plus I'd originally designed them to face +/- 45 degrees forward, so it was easy to just turn them around.

I'd been thinking of using rear-facing subcards in place of the omnis, which would provide about that amount of directionality without compromising bass extension too much or tonal quality of what is picked up from in front, but I don't have any subcards.  I've also thought about placing the Naiant X-8S bidirectionals coincident with the 4061 omnis so I could vary the pattern from forward facing through omni to rear-facing how ever I like as in the Schoeps Polar Flex system.  That would be the ultimate in terms of control- I could even vary the pattern with frequency (omnidirectional at LF routed to the Left and Right main channels, and rear facing cardioids for ambience and surround channels excluding the front sound) but that would would require two additional recording channels.   And both of those options would be too heavy to be able to be supported by the telescopic antennas at a 5' spread anyway.

The other modification was punching holes through my two big Shure windscreens for use on the left and right facing 4098 supercards.  That kept the heavy screens supported by and tight to the telescopic antennas, keeping things from flopping around and making setup, breakdown and hauling a bit easier.  As you can see from the one photo of the rig setup up low at the front rail, those B.A.Shures are due for replacement anyway, so I didn't feel too bad punching holes through them for this test run.  I think I'll make this a permanent feature once I replace the screens.

There was also a certain synchronicity in pulling out the Nerf APEs in that one of the bands playing this year was DSO (they did a mightily fine rendering of Cornell 5/8/77) and the last I'd recorded them was years ago at Langarado out in Big Cypress when Dan Healy was running their sound and I was first experimenting with the APEs.  He loved the antenna spaced omnis and signed one of the APE balls for me.  I think I blathered about that early in the thread, but it meant a lot to me.

Edit- here's the one Healy signed for me-

« Last Edit: June 27, 2017, 04:26:00 PM by Gutbucket »
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Offline heathen

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Re: Oddball microphone techniques
« Reply #221 on: June 27, 2017, 03:48:07 PM »
I've read most of this thread, with particular interest to your antenna mount for the small omnis.  One question I have, though, is about shock mounts.  It looks like you don't have any kind of shock mount for yours.  Is the natural "give" of the extended antenna enough to absorb any movement so that a shock mount isn't necessary?

I like how low profile the antenna idea is, and want to give it a try in my setup.  Any recommendations for how to attach antenna to a stand, short of fabricating a mount or just taping it to the stand?
Recording: Countryman B3 | CA-14 omnis | CA Ugly BB | AKG 460/ck61 | Studio Projects CS5 | Tascam DR-70D | Roland R-05
Playback: Monitor Audio Silver 10 | NAD C 275BEE | Emotiva TA-100
Headphones: Beyerdynamic DT 880 | ATH-M50 | Violectric HPA V90 | Raspberry Pi | HiFiBerry DAC+ Pro

Offline Gutbucket

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Re: Oddball microphone techniques
« Reply #222 on: June 27, 2017, 03:56:14 PM »
If you look closely in the above photos you'll see the splint I made to repair one of the antenna arms.  After a decade of use I finally broke one of them at Snarky Puppy's Ground Up fest in February in my haste to break down one night.  Somewhat surprised they made it this long without damage considering all they've been through over the past 10 years, often way FOB up front in the impact zone.

A few more from the section out in the Meadow (Peach stage) where there were numerous of spaced omni rigs flying this year-
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Offline Gutbucket

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Re: Oddball microphone techniques
« Reply #223 on: June 27, 2017, 04:07:25 PM »
I've read most of this thread, with particular interest to your antenna mount for the small omnis.  One question I have, though, is about shock mounts.  It looks like you don't have any kind of shock mount for yours.  Is the natural "give" of the extended antenna enough to absorb any movement so that a shock mount isn't necessary?

I like how low profile the antenna idea is, and want to give it a try in my setup.  Any recommendations for how to attach antenna to a stand, short of fabricating a mount or just taping it to the stand?

Well the omnis are pretty resistant to handling noise to begin with, and I find I don't really need shock mounts even with the directional mics.  If someone actually whacks the stand or something during a quiet section I can hear that in the directional mics, but not during the music.  I've never found it a problem which required further shock mounting, and the whole thing is much easier to rig with all these mics and far more compact without shock mounts.

I built a custom mount for the antennas out of aluminum bar-stock covered in heat-shrink.  It's like a very small mic bar with a hole in the center for stand mounting and the ends bent up at 45 degree angles.  The bend allows me to fold the antennas flush with the stand for travel, straight out perpendicular, or angled upwards.  I think I have detail photos of that posted earlier in the thread and will link to that post here once I find them.  But you can often just rig something and tape them in place with gaffer tape.  The  original silver pair I was using at the very start of this thread always remained attached to their own small center plastic thing, which originally stuck into a receptacle on the back of an old CRT TV.  I'd just tape the plastic thing to the painter pole and the antennas could still fold up.

Edit-
Here are photos of my antenna mount (from this early post in the thread).  I made two of these, one for each pair of telescopic antennas.  I can use them singly as shown here or use both together crossed at right angles to have antennas extending forward and back as well as left and right-




« Last Edit: June 27, 2017, 04:17:30 PM by Gutbucket »
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Offline 2manyrocks

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Re: Oddball microphone techniques
« Reply #224 on: June 27, 2017, 04:49:49 PM »
Fwiw, I've always taped my 4061s to something by the wire and the wiggle room in that I guess acts like a shock mount.  So small could probably fly them from a pair of trained butterflies.

 

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