Topic: Makers of Figure 8 mics/capsules

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Does anyone know for sure or have a link to any info on the capsule like a polar pattern graph?  Doesn't seem to be one on their website.

http://www.amptec.de/test/Alle%20Seiten/MBHO/MBHO%20capsules.html

The PDFs don't work, but the images are there.

[F.O.Bean]

I "took delivery" on a MBHO KA800 figure eight pattern capsule in September after "buying it" in April.  It came with absolutely no documentation. It's definitely a single diaphragm and  I'm assuming it's a symmetrical design as most other MBHO products I have seem closely related to Schoeps microphone designs.  Does anyone know for sure or have a link to any info on the capsule like a polar pattern graph?  Doesn't seem to be one on their website.

That said, I'm very happy with it based on the few MS recordings I've done - especially running center stage lip about waist high.  Awesome stereo image and picks up way more vocals than any other stereo pattern I have run on stage.  Lately I've been pairing it with a DPA 4022 for the mid rather than a Ho card.  Gives it better overall bass response esp picking up the kick drum from a distance.  I'm loving my foray into MS recording.  From further back though seems I'm better of running cards or hypers.

Thanks for the response

[Gutbucket]

Does anyone know for sure or have a link to any info on the capsule like a polar pattern graph?  Doesn't seem to be one on their website.

http://www.amptec.de/test/Alle%20Seiten/MBHO/MBHO%20capsules.html

The PDFs don't work, but the images are there.

MBHO KA800-

The photo sure makes it look like a stereo mic, do two individual capsules somehow link together or is that photo incorrect?


Granted the print is small, but I'm having a hard time reconciling their polar plot and on-axis response graph-

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The photo sure makes it look like a stereo mic, do two individual capsules somehow link together or is that photo incorrect?

I think it was taken while sitting on a mirror.

[boojum]

Not a mirror image.  There is engraving on the upper module which is not on the lower, assuming the "mirror" is at the horizontal seam.

[F.O.Bean]

so it IS a side-address capsule, right? Meaning that the 0* marking needs to be pointing TOWARDS the soundsource, correct?

[dbindc]

Gutbucket is on target.  This photo appears to be two KA 800 capsules attached in the manner of a stereo ribbon mic like a Royer.  My KA800 capsule looks like just the top half.  I've been pointing the end in the direction of the cardiod mic and aligning the 0 degree mark to the right side as close to perpendicular as possible.

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Gutbucket is on target.  This photo appears to be two KA 800 capsules attached in the manner of a stereo ribbon mic like a Royer.  My KA800 capsule looks like just the top half.  I've been pointing the end in the direction of the cardiod mic and aligning the 0 degree mark to the right side as close to perpendicular as possible.

thanks, I missed the lack of the angle which would have indicated the mirror.

[F.O.Bean]

Gutbucket is on target.  This photo appears to be two KA 800 capsules attached in the manner of a stereo ribbon mic like a Royer.  My KA800 capsule looks like just the top half.  I've been pointing the end in the direction of the cardiod mic and aligning the 0 degree mark to the right side as close to perpendicular as possible.

Awesome So the "top" of the capsule points towards the soundsource, while the 0* marking points towards the right, perpendicular to the soundsource Thanks brah!!!

I couldve sworn that the 0* marking was always supposed to be to the left side tho

[DSatz]

Gutbucket, hoping I don't sound too much like the Borg here, but trying to "reconcile" a frequency response graph with a polar response graph is futile. The curves in a polar diagram are independent of the microphone's on-axis frequency response.

The purpose of a polar diagram is to let you see the similarity or note any anomalies in directional response in the different frequency ranges that the microphone picks up. For each frequency that's displayed in the polar diagram, the actual 0-degree sensitivity of the microphone at that frequency is not taken into consideration. Instead, the polar diagram shows it as "0 dB," and it becomes the reference point for the rest of the curve at that one frequency. This process is then repeated for each frequency on the list.

If they didn't do that, some of the curves might go well beyond the circle (think of a diffuse-field omni microphone whose response is up 6 dB at 8 kHz) while others would be tiny (think of a speech cardioid microphone which is down 12 dB at 50 Hz). If you wanted to make a graph like that, you certainly could, by taking the frequency response curve, looking up the 0-degree sensitivity at each of the relevant frequencies, and then applying those values as "multipliers" to the size of the polar graph for that frequency.

But in the normal way of drawing a polar diagram, the frequency response is specifically excluded as a factor because that information is already contained in the frequency response graph--so it would be redundant, and for microphones with non-flat frequency response, kind of messy looking.

As a test, see whether this way of putting things now makes sense to you: The ability to "reconcile" the two kinds of graph would only be an indication of whether the microphone has flat response or not--and the frequency response graph already gives you that information, so the polar graph doesn't.

--best regards

P.S. (added later): Looking back at your message, I see that MBHO apparently scaled each of the individual polar curves by some seemingly arbitrary factor. I agree that this is distracting, but actually in principle, it's "no more artificial" than the usual way is, where each individual curve starts at 0 dB for 0 degrees. I assume it's just their way of trying to present the different shapes without having to draw lines to label them.

[Gutbucket]

Information assimilated.

Thanks for the clarification, the scaled response curves of the polar plot (not normalized to 0db at 0 degrees) is what threw me.  Since the polar plot response curves didn't all line up at 0 degrees like I've come to expect of most polar plots with your guidance, it seemed to me that they'd plotted the diagram using the absolute frequency response values.  If that was the case, the data from a vertical 'slice' of polar plot at 0 degrees should match the frequency response graph.  That's how I thought all polar plots worked until you previously instructed me as to how the typical polar plot is displayed (response normalized to 0db at 0 degrees).

When I saw the plot for this capsule I thought, "Hey, that's showing the absolute response on the polar plot like I originally imagined they worked." Yet that doesn't appear to be the case either since the db values for 0 degrees don't match the frequency response graph.

Would it be safe to summarize the information displayed on a polar plot in the following way? - A 'typical' polar response plot shows the change in response, not the absolute response for each angle in the horizontal plane?

Thanks again for your help in understanding this.

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Gutbucket is on target.  This photo appears to be two KA 800 capsules attached in the manner of a stereo ribbon mic like a Royer.  My KA800 capsule looks like just the top half.  I've been pointing the end in the direction of the cardiod mic and aligning the 0 degree mark to the right side as close to perpendicular as possible.

Awesome So the "top" of the capsule points towards the soundsource, while the 0* marking points towards the right, perpendicular to the soundsource Thanks brah!!!

I couldve sworn that the 0* marking was always supposed to be to the left side tho

Well, it depends on what your using it for, it's a "side address" cap, I'm relatively sure of that (almost all fig8s are), but where you point the positive lobe depends on what your doing.

If you've got one handy, set up an MS setup (both "pointed" forward, so your card toward 0 and the fig8 toward 90. Snap your fingers a couple of times at 90, 0, and 270. Then do the MS decode in post and see what happens what you get. If you remember or take notes on what side and what was there when you did the first snap, then you'll see what the positive lobe is.

[Len Moskowitz (Core Sound)]

I'm primarily interesting in capsules, especially ones that can be purchased and flown in an active style, but any info is appreciated.

Tetrahedral ambisonic mics, like our TetraMic and the mics from SoundField Ltd., can do the job well.

With no exaggeration, our TetraMic is probably one of the finest figure-8 mics in the world.  It also is one of the finest Blumlein arrays in the world.  And M/S.  And surround.

(Yes, you read that correctly: TetraMic can function as single mic, a pair of mics, or as many coincident mics as you desire.)

[F.O.Bean]

Gutbucket is on target.  This photo appears to be two KA 800 capsules attached in the manner of a stereo ribbon mic like a Royer.  My KA800 capsule looks like just the top half.  I've been pointing the end in the direction of the cardiod mic and aligning the 0 degree mark to the right side as close to perpendicular as possible.

Awesome So the "top" of the capsule points towards the soundsource, while the 0* marking points towards the right, perpendicular to the soundsource Thanks brah!!!

I couldve sworn that the 0* marking was always supposed to be to the left side tho

Well, it depends on what your using it for, it's a "side address" cap, I'm relatively sure of that (almost all fig8s are), but where you point the positive lobe depends on what your doing.

If you've got one handy, set up an MS setup (both "pointed" forward, so your card toward 0 and the fig8 toward 90. Snap your fingers a couple of times at 90, 0, and 270. Then do the MS decode in post and see what happens what you get. If you remember or take notes on what side and what was there when you did the first snap, then you'll see what the positive lobe is.

Isnt 0* supposed to be on one particular side tho? Like left or right?

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Isnt 0* supposed to be on one particular side tho? Like left or right?

Each mic maker could intend for that sign to mean something different with orientation interpretation. I'm not sure that they would, and I personally would anticipate it to be the left side (or positive lobe is a more accurate term I guess), but the easiest way is to check it out.