Why you should never use multi pattern mics

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Not arguing that, but there is the other argument for some of the side benefits of just having two capsules in cardioid mode. Which some might think defeats the point, but there are readily observable differences in proximity effect and plosive handling in close-mic'ing situations (due to difference in directionality at lower frequencies), which the white paper Kong shared elaborates on.
keep in mind that this is based on the simplest mathematical models of both. it doesn't necessarily mean much with regards to chambered designs. the k67 is NOT a simple two-diaphragm capsule with resistance between. It has a chamber in the middle, which acts a little differently than just acoustic resistance. Not to mention the double, triple, or even quadruple chamber models out there with both 1 and 2 diaphragms. this paper does ring true for the behavior I've observed on true "simple" 2 diaphragm capsules, like the k47, and i'm sure it predicts behavior well between matched examples, but its applicability beyond that is a bit questionable. Not saying it's not, but I don't think I could definitively say that it is either. The JLI103 you evaluated a few days ago which you mentioned had both less boom and fewer pops is single-diaphragm and chambered.
 
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keep in mind that this is based on the simplest mathematical models of both. it doesn't necessarily mean much with regards to chambered designs. the k67 is NOT a simple two-diaphragm capsule with resistance between. It has a chamber in the middle, which acts a little differently than just acoustic resistance. Not to mention the double, triple, or even quadruple chamber models out there with both 1 and 2 diaphragms. this paper does ring true for the behavior I've observed on true "simple" 2 diaphragm capsules, like the k47, and i'm sure it predicts behavior well between matched examples, but its applicability beyond that is a bit questionable. Not saying it's not, but I don't think I could definitively say that it is either. The JLI103 you evaluated a few days ago which you mentioned had both less boom and fewer pops is single-diaphragm and chambered.

Interesting. I was reading up on some of this stuff a few weeks back and came across more info from Shure (who seems to take a keen interest on the topic), regarding the ksm42.

https://service.shure.com/s/article/dual-diaphragm-design-control-of-proximity-effect?language=en_US
Shure: If the sound source is close to the microphone, there is a time delay difference between the sound pressures on either side of the diaphragm, along with the increased level of sound due to the closer distance (inverse square law). This results in proximity effect, which is the increase in bass response as a sound source gets closer to the microphone. Proximity effect influences frequencies below 1000Hz and the closer the sound source is to the microphone, the greater the effect becomes on lower frequencies. Proximity effect only occurs with directional microphones. Omnidirectional microphones do not exhibit proximity effect as the rear of the diaphragm is blocked.

Continued ...
At lower frequencies, the passive diaphragm partially blocks the sound from reaching the rear of the active diaphragm. The lower the frequency, the more the sound is blocked. Like an omnidirectional microphone ...

I don't know percentage of this is marketing speak, truth, or over-simplification, but am I reading this correctly that simply blocking the rear of the diaphragm is what's responsible for the reduction in proximity effect? Because that would fill in at least a few gaps in my understanding of all this.
 
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Interesting. I was reading up on some of this stuff a few weeks back and came across more info from Shure (who seems to take a keen interest on the topic), regarding the ksm42.

https://service.shure.com/s/article/dual-diaphragm-design-control-of-proximity-effect?language=en_US


I don't know percentage of this is marketing speak, truth, or over-simplification, but am I reading this correctly that simply blocking the rear of the diaphragm is what's responsible for the reduction in proximity effect? Because that would fill in at least a few gaps in my understanding of all this.
blocking or not blocking the rear of the diaphragm is what's responsible for all polar behavior ever
 
I've been very interested in hearing something in regards to off-axis coloration related to this topic.

Mainly, I record guitar and vocal at the same time using the nulls of figure-8 to isolate my guitar from my vocals.
As a result I'm usually between 30 and 45 degrees off axis with both microphones.

Figure-8 seems to record very fairly off axis in the higher frequency range, even the dual diaphragm LDCs.
If I try and isolate guitar and vocals using Cardioid, the off axis coloration is not pleasant.

Would someone shed some insight into this for me.
 
blocking or not blocking the rear of the diaphragm is what's responsible for all polar behavior ever

Got it. Thanks. This actually has me thinking now about things I've read about Electrovoice and their variable-D design. And how their ports are all set up with the idea of lowest frequencies entering bottom port, etc. Now that's actually starting to make a little more sense, because I'm guessing they're leveraging this acoustic property to block/hinder lower frequency access to the rear of the diaphragm? (just throwing that out there)
 
Only if you're trying to use a dual-diaphragm as a distance mic. And who even does that?
Errh! The BBC recorded the Proms in the Royal Albert Hall for many years with AKG C24 in Fig8 as the main Blumlein pickup. Bernhard Weingartner originally designed it for them for this purpose. It replaced a pair of 4038 ribbons and was replaced by a Calrec Soundfield Mk3A (my baby). These were/are some of the best orchestral recordings ever made. Of course you may be better than the BBC at recording and disagree :)
 
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Figure-8 seems to record very fairly off axis in the higher frequency range, even the dual diaphragm LDCs.
If I try and isolate guitar and vocals using Cardioid, the off axis coloration is not pleasant.

Would someone shed some insight into this for me.
On MicBuilders Files, I have a full report on a 'C12' variable pattern type microphone and show off-axis responses in all modes. zephyr.doc
One reason why the original Soundfield Mike sounds good is that it's frequency response is flatter than anything else in ALL directions and modes. This is essential for capturing the sound of a good hall.
Of course if you only use your LDC in an anechoic sound booth, you don't really need this :)
 
Of course if you only use your LDC in an anechoic sound booth, you don't really need this :)
What I really need is an 'amateur artificial intelligence sound booth' that makes my guitar playing and vocal quality sound better.
Sometimes I wonder why I worry about technical stuff so much, when it's my performance quality that really needs the help.
 
Errh! The BBC recorded the Proms in the Royal Albert Hall for many years with AKG C24 in Fig8 as the main Blumlein pickup.

A lot of the Chesky big band jazz recordings made by Bob Katz also used a C24 for Blumlein or M/S main pickup. Maybe only pickup, a lot of those Chesky recordings don't use spot mics so that you don't have any issues with cancellation or mismatches between the main pair and the spot mic highlights. All the ones I have heard sound gorgeous.
 
I'll quote myself from the original post once again

I think those last two posts were actually in response to keithricker:
Only if you're trying to use a dual-diaphragm as a distance mic. And who even does that?

So the answer to who does that is at least BBC and Chesky. Although given the difficulty in conveying subtlety in forum text, it is likely that the original quip was just sarcasm.
 
I think those last two posts were actually in response to keithricker:


So the answer to who does that is at least BBC and Chesky. Although given the difficulty in conveying subtlety in forum text, it is likely that the original quip was just sarcasm.
Ok, got it wrong, sorry.
 
This came up in another forum. I think it was Martin Scheider or even Wolf himself who confirmed it was Bernhard Weingartner who designed the CK12 & C12 for AKG.
My info is a bit more direct.
The history of Calrec is that Clem Beaumont, my mike mentor, built a DRS and showed it to Bernhard when AKG used to come to the Audio Show when it was at Harrogate, Yorkshire. They became great friends and his encouragement led to the formation of Calrec and later the Soundfield Microphone and my involvement.
Martin works for Neumann, sorry. If you have some info, ok, but it seems you don’t. Konrad specifically wrote in publications of the time about the development of the microphone and capsule. If you go digging at World Radio History you will find confirmation of that a few times over. I’m not saying you are necessarily wrong, just that for me, I’m probably not changing my mind on it yet. :)
 
Martin works for Neumann, sorry. If you have some info, ok, but it seems you don’t. Konrad specifically wrote in publications of the time about the development of the microphone and capsule. If you go digging at World Radio History you will find confirmation of that a few times over.
I think you will find that when Mr. Schneider said this, the AKG & Neumann R&D departments were already under the Harman Empire (possibly even the same roof) so he had direct access to Konrad.

But I would appreciate a link to the World Radio History article by Wolf.

Alas, Clem Beaumont has passed on so I can't re-confirm his memories of Bernhard W and his claims :(
 
AKG & Neumann R&D departments were already under the Harman Empire

AKG is owned by Harman International, but Neumann is owned by Sennheiser (at least currently, and I don't believe Neumann was ever part of Harman).
The Harman International Pro Audio solutions brochure currently lists as subsidiaries AKG, AMX, BSS, Crown, dbx, JBL, Lexicon, Martin, Soundcraft, and Studer.
 
Just try doing some web searches, whether you find the article or not, you’ll find all sources state he invented the mic. It sounds like you may have got a few things mixed up.
 
Du.uuh! First hit is an evil Harman page pretending to be AKG :eek: :whistle:
AKG 75th Anniversary Retrospective: C Series Microphones – The Evolution of a Studio Icon –

I think this came up in Micbuilders a long time ago .. which will take a lot of searching to find.

IIRC, Martin said he would ask Wolf who confirmed it was mostly Bernhard's design. A couple of years ago, I tried to get in touch with Bernhard but was told he was getting very senile and forgetful. He's no longer involved with day-to-day activities at Neutrik but still appears occasionally.

I don't think I remember wrong cos it was such an important part of my personal mike design journey. Of course Bernhard may have been lying but I don't think so :)
 
Coming very late to this discussion, I noticed a few posts, particularly the OP mentioning "phasing issues".
Phase is an old endemic scapegoat, often used by barely qualified people to support their criticism of a particular equipment.
I'm not saying it's the case for kingkorg or Recording Engineer.
If there was no phase, there would simply be no cardioid mics.
Single diaphragm cardioids are cardioid because of an acoustic phase device, when dual-diaphragm rely on simple spacing, but in the end it's the same principle that is at work. Of course they have a different response but they both have "phase issues".
 

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