Topic: Makers of Figure 8 mics/capsules

[page]

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

I know that Neumann and Schoeps make 8 caps *and* have active systems of some sort, while Milab and Busman make mics that can send an 8 signal but that comes out of a full body (usually switchable at that). What else is there?

This is what provoked my question: 
http://taperssection.com/index.php/topic,115533.msg1546249.html#msg1546249

[OOK]

MBHO.......................

[vanark]

I recently saw an Oktava Figure 8 capsule for the MK-012 bodies.

[noahbickart]

akg ck94 for the Blue line series.

-Noah

[page]

MBHO.......................

akg ck94 for the Blue line series.

I'd forgotten both of those  (especially MBHO). Thanks!

I recently saw an Oktava Figure 8 capsule for the MK-012 bodies.

heh, the ghetto 8, fairs fair though, I asked. Thanks.

[OOK]

MBHO.......................

Best bang for the buck IMO....

[John Willett]

Sennheiser MKH 30.

As far as I know most people make figure-8 mics from two cardioid capsules, back-to-back.

There are only 3 condenser fig-8 mics that are real fig-8s with a single diaphragm:-

Sennheiser MKH 30 - fully symmetrical, electrically and acoustically.
Neumann AK 20 - acoustically symmetrical
Schoeps - not symmetrical, the rear lobe is slightly different at the gighest frequencies.

I hope this helps.

[DSatz]

John, the Schoeps MK 8/CCM 8 is definitely symmetrical. I believe you may be referring to the published polar diagram, which shows a ca. 2 dB decrease in relative response at 16 kHz from 180 degrees. It is strange to me that they use this curve; I hope to find out why. But the capsule's internal physical construction is entirely symmetrical--in principle exactly as the Neumann AK 20's is, with one "active" backplate plus an acoustically identical "backplate" on the other side of the diaphragm which is not active electrically.

--best regards

[John Willett]

John, the Schoeps MK 8/CCM 8 is definitely symmetrical. I believe you may be referring to the published polar diagram, which shows a ca. 2 dB decrease in relative response at 16 kHz from 180 degrees. It is strange to me that they use this curve; I hope to find out why. But the capsule's internal physical construction is entirely symmetrical--in principle exactly as the Neumann AK 20's is, with one "active" backplate plus an acoustically identical "backplate" on the other side of the diaphragm which is not active electrically.

Thanks for letting me know.

Yes, I was going from the published curve which clearly shows a rear attenuation at high frequencies.

I had also heard that it did not have a front plate.

Unless it used to be as I said and they have now changed it and forgotten to update the polar-pattern.

Please let me know if you find out as I do not like to give incorrect infrmation.

Thanks.

[DSatz]

John, all single-pattern figure-8 capsules and microphones that Schoeps has ever made have followed a symmetrical, single-diaphragm design. Their three-pattern capsules (which, while using only a single diaphragm, include a figure-8 setting) are perhaps a different story in a way: During the first half of the 1960s, Schoeps used a true push-pull design for this type of capsule.

But then they changed over to the design which they still use today, which is acoustically symmetrical but not push-pull. So with tongue in cheek, one could perhaps say that they went from a "Sennheiser-like" approach (the CMT 26 even used an RF amplifier circuit!) to a "Neumann-like" approach--though it was decades before Sennheiser or Neumann made any such microphones ...

--best regards

[page]

During the first half of the 1960s, Schoeps used a true push-pull design for this type of capsule. But then they changed over to the design which they still use today, which is acoustically symmetrical but not push-pull.

Whats the real-world difference between the two that would cause them to make the shift? easier production or is there something tangible to the end-user? Just curious. Thanks.

[F.O.Bean]

what about the MBHO KA800A Its a side-address capsule just like the MK8 is, isnt it Wouldnt it technically be a symmetrical capsule as well The polar pattern I have seen of it was def symmetrical......I LOST all of my bookmarks when I reformatted tho I forgot to save that last bookmark

Anyway......I'd love to know the answers to those.....

[DSatz]

page, first I should "disclaim" that I've done a lot of translating and editorial consulting for Schoeps on a freelance basis, but I have no particular formal relationship with the company and am certainly not a spokesperson for them. My views are pretty much my own (or at least I like to imagine that they are).

That said: Some time back I asked the same question of two engineers at Schoeps, but they aren't the people who made the decision 40+ years ago. So I can only give you my impression of their impression, or what they chose to share with me--which is basically that the push-pull capsule design brought additional complexity without any notable sonic benefit. And I don't know whether it's a coincidence or not, but the capsules which used this design are among the few types that Schoeps won't accept for repair any more.

In March, 1981 two leading engineers from Sennheiser presented an AES paper which set forth the theory behind push-pull capsule design. The objective findings of that paper aren't in any dispute that I know of: A push-pull capsule can have lower distortion than an otherwise comparable design that isn't push-pull. But the push-pull approach, by itself, is no guarantee of either a low distortion figure OR of a good-sounding microphone. It isn't clear to what degree the distortions canceled by a push-pull design are ever audible in capsules that don't use the technique. The 1981 paper didn't discuss audibility, and I for one have seen no further papers on this topic. Opinions, sure--but facts, not so much. And this seems a mite strange to me.

I wonder whether Sennheiser engineers ever made comparison recordings while they were developing their capsule designs back then. They could fairly easily have made identical microphones with and without the push-pull technique, and then recorded the same music with identically-placed microphones of both kinds.

If that were being done today, they could even make stereo recordings with both kinds of microphone on a four-track digital recorder, then subtract the one recording from the other to hear just the difference (presumably the distortion that the push-pull design cancels out). That's something that I'd really want to hear before forming too strong an opinion either way about this.

--best regards

[John Willett]

page, first I should "disclaim" that I've done a lot of translating and editorial consulting for Schoeps on a freelance basis, but I have no particular formal relationship with the company and am certainly not a spokesperson for them. My views are pretty much my own (or at least I like to imagine that they are).

That said: Some time back I asked the same question of two engineers at Schoeps, but they aren't the people who made the decision 40+ years ago. So I can only give you my impression of their impression, or what they chose to share with me--which is basically that the push-pull capsule design brought additional complexity without any notable sonic benefit. And I don't know whether it's a coincidence or not, but the capsules which used this design are among the few types that Schoeps won't accept for repair any more.

In March, 1981 two leading engineers from Sennheiser presented an AES paper which set forth the theory behind push-pull capsule design. The objective findings of that paper aren't in any dispute that I know of: A push-pull capsule can have lower distortion than an otherwise comparable design that isn't push-pull. But the push-pull approach, by itself, is no guarantee of either a low distortion figure OR of a good-sounding microphone. It isn't clear to what degree the distortions canceled by a push-pull design are ever audible in capsules that don't use the technique. The 1981 paper didn't discuss audibility, and I for one have seen no further papers on this topic. Opinions, sure--but facts, not so much. And this seems a mite strange to me.

I wonder whether Sennheiser engineers ever made comparison recordings while they were developing their capsule designs back then. They could fairly easily have made identical microphones with and without the push-pull technique, and then recorded the same music with identically-placed microphones of both kinds.

If that were being done today, they could even make stereo recordings with both kinds of microphone on a four-track digital recorder, then subtract the one recording from the other to hear just the difference (presumably the distortion that the push-pull design cancels out). That's something that I'd really want to hear before forming too strong an opinion either way about this.

When I talked to the Sennheiser designer of the push-pull capsule he did tell me that it was much easier to do with an RF condenser than an AF - due to the fact that the RF capsule is low impedance and the AF very high impedance with the added problem of having an active backplate in the front of the diaphragm.

Did you ever hear the Sennheiser demo. CD that they did in 1985 when they launched the MKH 40?

It had examples of IM-distortion of the MKH 40, a top quality LDC and a top quality SDC.

If you didn't and want to, I'm happy to send you a copy.

The CD was deleted many years ago, but I have a copy on MY PC - I replaced the music samples with stuff I recorded myself and documented the microphones and positioning.

[dbindc]

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.