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Author Topic: DPA 4098H miniature supercardioid  (Read 6390 times)

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DPA 4098H miniature supercardioid
« on: August 09, 2013, 10:57:22 AM »
Picked up a pair of these but haven’t yet used them.  Very similar specifications to the 4060, which should work well for some of the configurations I’m looking forward to trying.  These are designed as hanging choir microphones and are likely to be better suited to far-field recording than most of their directional miniature microphones designed for close-mic'ing vocals and instruments, both in frequency response and in sensitivity.

Some specifications and graphs from the DPA website:

DPA 4098H
Pressure gradient supercardioid pre-polarized condenser
Frequency range: 20 Hz to 20 kHz, ± 2 dB 80 Hz to 15 kHz @ 20 cm (7.9 in) distance: with 3 dB diffuse field boost at 8 to 15 kHz
Sensitivity, nominal ± 3 dB at 1 kHz: 20 mV/Pa; -34 dB re. 1 V/Pa
Equivalent noise level, A-weighted: Typ. 23 dB(A) re. 20 μPa (max. 26 dB(A))
Equivalent noise level, ITU-R BS.468-4: Typ. 35 dB (max. 38 dB)
S/N ratio (A-weighted), re. 1 kHz at 1 Pa (94 dB SPL): 71 dB(A)
Total harmonic distortion (THD): <1 % up to 123 dB SPL peak; <1 % up to 120 dB SPL RMS sine
Dynamic range: Typ. 100 dB
Max. SPL, peak before clipping: 134 dB
Output impedance: From Microdot: 30 to 40 ohm; from DAD6001: 100 ohm
Cable drive capability: Up to 300 m (984 ft) with DAD6001 XLR adapter
Common mode rejection ratio (CMRR): > 60 dB from 50 Hz to 15 kHz with DAD6001 XLR adapter
Power supply (for full performance): Min. 5 V – max. 50 V through DPA adapter; with DAD6001: 48 V phantom power ±4 V
Current consumption: 1.5 mA. 3.5 mA with DAD6001 XLR adapter
Connector: MicroDot; 3 pin XLR-M from DAD6001 XLR adapter
Microphone diameter: 10 mm (0.39 in)
Capsule diameter: 5.4 mm (0.2 in)
Microphone length: 154 mm (6.1 in)
Gooseneck length: 95 mm (3.7 in)
Polarity: Positively increasing sound pressure produces positive going voltage at MicroDot pin (and pin 2 on DAD6001 XLR adapter)






Some close-up photos I took the other day follow.  The gold rectangular internal capsule appears to be identical to the 406x, only with a short interference tube made from a very dense mesh replacing the short/long omni grids, and two small vents at the back of the capsule housing.  The microdot termination, powering requirements, self-noise, sensitivity, max SPL, etc are all the same as the 4060.

Photos-
« Last Edit: August 15, 2016, 10:22:38 AM by Gutbucket »
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Re: DPA 4098H miniature supercardioid
« Reply #1 on: August 09, 2013, 11:00:44 AM »
At some point I'll test how the interference tubes perform when placed on the 4060/4061 capsules, but lacking the rear vents, I don't expect that you could turn a 4060 into a 4098 simply by swapping the grid for the tube.  The dense stainless steel mesh or perforation of the interference tube is very tight, removing one and putting it to my lips I can blow air through the mesh, but only with significant of resistance.  The tubes are open at both ends.
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Re: DPA 4098H miniature supercardioid
« Reply #2 on: August 09, 2013, 11:05:16 AM »
Far end of interference tube and the 406x looking capsule but with rear vented housing.  Two vents on opposing sides-
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Re: DPA 4098H miniature supercardioid
« Reply #3 on: August 09, 2013, 11:08:02 AM »
View showing vents and interference tubes without foam windscreen.  The vents use the same stainless screen as the interference tubes-
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Re: DPA 4098H miniature supercardioid
« Reply #4 on: August 09, 2013, 11:16:51 AM »
The two small vents on the back of the capsule housing are part of what makes this a card. The interference tube is only to increase directionality. With out the vents on the back of the capsule you will not have a card polar pattern. Even with the interference tube.
The combination are what help it do its magic. I would suspect that they are using a Helmholtz tuning to the back ports to make this possible.
Can you take a picture of the back of the gold capsule thats where these vents must be greeted by a tube? to direct the back pressure behind and below the capsule housing in the back.
Chris
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Re: DPA 4098H miniature supercardioid
« Reply #5 on: August 09, 2013, 11:17:25 AM »
Plans for use-
A few different ideas.  Primarily, I plan to try them as center front/rear facing cardioids between 2m spaced 4060s in a surround decca-tree like arrangement that has worked well recording outdoor concerts.  As some of you are aware from previous threads or real life, I’ve previously used four 4060s mounted on telescopic TV antennas for this, sometimes with the omnis mounted in small spheres to give them some directionality. A few years ago I eliminated the spheres and started spacing the Left/Right omnis 2m apart instead of the 1m I would space them if I was only using two mics.  Last year I started substituting full sized Gefell cardioids or borrowed miniature AT cardioids for the front/rear mics which reduced the need for as much front/rear spacing using omnis and better isolated the direct sound in the front center mic and the audience reaction/room sound in back center mic.  The increased front/rear isolation from the cardioids combined with the increased spacing of the left/right omnis worked very well.  These 4098 will allow me to substitute DPA miniature cardioids for the full sized cards, with a sound that should be very well matched with the DPA 4060 omnis, making the 4 channel rig very compact and all low voltage powered.

I’m curious to check out their low frequency response used at taper distances, but in the configuration described above, reduced low frequency response in the center mics is not a problem and may be advantageous.  The 2m spaced Left/Right omnis provide the low end.
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Re: DPA 4098H miniature supercardioid
« Reply #6 on: August 09, 2013, 11:19:10 AM »
Plans for use-
A few different ideas.  Primarily, I plan to try them as center front/rear facing cardioids between 2m spaced 4060s in a surround decca-tree like arrangement that has worked well recording outdoor concerts.  As some of you are aware from previous threads or real life, I’ve previously used four 4060s mounted on telescopic TV antennas for this, sometimes with the omnis mounted in small spheres to give them some directionality. A few years ago I eliminated the spheres and started spacing the Left/Right omnis 2m apart instead of the 1m I would space them if I was only using two mics.  Last year I started substituting full sized Gefell cardioids or borrowed miniature AT cardioids for the front/rear mics which reduced the need for as much front/rear spacing using omnis and better isolated the direct sound in the front center mic and the audience reaction/room sound in back center mic.  The increased front/rear isolation from the cardioids combined with the increased spacing of the left/right omnis worked very well.  These 4098 will allow me to substitute DPA miniature cardioids for the full sized cards, with a sound that should be very well matched with the DPA 4060 omnis, making the 4 channel rig very compact and all low voltage powered.

I’m curious to check out their low frequency response used at taper distances, but in the configuration described above, reduced low frequency response in the center mics is not a problem and may be advantageous.  The 2m spaced Left/Right omnis provide the low end.

I have to assume your low frequencies will not be as good as the 4060 only because for card you need space behind the capsule ( back plate )  for low frequency response to be decent. Where as omni only needs a tight seal and enough holes in the back plate ( tuning )  to give good bottom end response.
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Re: DPA 4098H miniature supercardioid
« Reply #7 on: August 09, 2013, 11:25:50 AM »
The two small vents on the back of the capsule housing are part of what makes this a card. The interference tube is only to increase directionality. With out the vents on the back of the capsule you will not have a card polar pattern. Even with the interference tube.
The combination are what help it do its magic. I would suspect that they are using a Helmholtz tuning to the back ports to make this possible.

Chris

That's exactly what I was thinking.  Besides checking out what happens when putting these interference tubes on 4060/4061 capsules, I should see what happens putting the omni +3dB short grids on the 4098s.

I did notice that the solid tube portion of the interferece tube appears to be the same length as the omni short grid, probably responsible for the similar +3dB boost from 8-15kHz.  Another Helmholtz resonance thing.
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Re: DPA 4098H miniature supercardioid
« Reply #8 on: August 09, 2013, 11:34:19 AM »
I have to assume your low frequencies will not be as good as the 4060 only because for card you need space behind the capsule ( back plate )  for low frequency response to be decent. Where as omni only needs a tight seal and enough holes in the back plate ( tuning )  to give good bottom end response.

I don't expect them to have anywhere close to low frequency omni response, although probably more bottom end than the miniature DPA cardioids designed for close-mic'ing withing the proximity effect zone. I expect them to have DPA mid/high clarity and to sound somewhat thin below 500Hz used alone, but that frequency resoponse should be complemented and compensated for by using them in combination the 4060s.

Another member here uses them immediately adjacent to 4060 or 4063 on glasses, mixing the two to blend the mid/high directionality of the supercards with the flat low frequency response of the omnis.
« Last Edit: August 09, 2013, 01:05:36 PM by Gutbucket »
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Offline Todd R

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Re: DPA 4098H miniature supercardioid
« Reply #9 on: August 09, 2013, 01:30:04 PM »
Interesting!

Thanks for the info on these.  Keep us posted on what you think.

Q for these:  Are they vertically addressed or axially addressed?  An interference tube with a vertical capsule at the bottom throws me.
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Re: DPA 4098H miniature supercardioid
« Reply #10 on: August 09, 2013, 03:00:22 PM »
Looks very cool!  I hope they serve you well, and they become a fixture for low-pro recording!!  I would have considered these had I not purchased two new sets of mics during the SP sale today!  Ended up with two complete set ups for the price of one of these mics though  :'(   Nevertheless, very interested to see how these fare in use.
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Re: DPA 4098H miniature supercardioid
« Reply #11 on: August 09, 2013, 03:38:41 PM »
Q for these:  Are they vertically addressed or axially addressed?  An interference tube with a vertical capsule at the bottom throws me.

Hey Todd,
These are axially addressed, and the 406x omnis are axially addressed too- the sideways facing capsule is always completely buried within the barrel of the grid when the grid is installed. The outer edge of the barrel rim of the grid where the protective screen portion starts is maybe a millimeter or so above the top edge of the capsule with the short +3dB grid installed, and significantly above it with the +6dB grid installed.  But as you know, off-axis sensitivity doesn't fall off very much until high very high in the frequency range with very small diameter omnis anyway.  I can hear a very slight high end response difference on and off-axis with 4060/4061 while testing them at home and DPA's published polars confirm that, but it’s really minimal compared to non-miniature omnis.  I never confirmed if orientation makes any discernable difference in real world taping situations, but I still point them appropriately when I can. 


« Last Edit: August 09, 2013, 03:56:09 PM by Gutbucket »
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Re: DPA 4098H miniature supercardioid
« Reply #12 on: August 09, 2013, 03:45:49 PM »
Looks very cool!  I hope they serve you well, and they become a fixture for low-pro recording!!  I would have considered these had I not purchased two new sets of mics during the SP sale today!  Ended up with two complete set ups for the price of one of these mics though  :'(   Nevertheless, very interested to see how these fare in use.

I've wanted to try these out for a while, and was finally able to aquire a pair at a significantly reduced cost that made it attractive to do so.  The integral goose-neck will be and advantage with the application I described above.  Not sure if that feature would be a benefit or hinderance for stealth applications, depends on the setup I guess.

Enjoy your new mics!
« Last Edit: August 09, 2013, 03:57:07 PM by Gutbucket »
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Re: DPA 4098H miniature supercardioid
« Reply #13 on: August 09, 2013, 03:55:46 PM »
The interference tube on the omni ought to increase directionality, but not as much as a cardioid (without tube).  You could end up with something egg-shaped at frequencies where the tube is effective.

I think that's a potentially interesting application if the FR works out OK.

Hi Jon,
I’m curious about your thoughts on what seems to me to be a unique acoustic design here (as well as Chris's and anyone else knowledgeable about physical mic design).  When I found the two small vents at the bottom of the capsule housing I realized this is not simply a 406x omni capsule housing with an interference tube installed on it.  Yet it also wouldn't seem to be a traditional cardioid design with a delayed acoustic path to the back of the diaphragm.  Without dissecting it, it would seem to be a pressure omni mounted inside in a hollow tube, with the diaphragm not terminating the tube, but small vents at the back end of the tube and an interference tube at the front end of it, and the fine stainless mesh providing acoustic resistance at both the rear vents and along the sides of the interference tube.  The omni sampling pressure variation in the tube between the entry points at either end.

I’ll take a closer look tonight, maybe shining a bright light at the vents on the base of the housing while looking into the front of the capsule opening to check if I can see light around the edge-on omni housing.
« Last Edit: August 09, 2013, 03:58:29 PM by Gutbucket »
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Re: DPA 4098H miniature supercardioid
« Reply #14 on: August 09, 2013, 06:38:40 PM »
I have been using these for several years (since they first came out), also more recently the 4081s, same mic different cable and better in a croakie.  I run them with a pair of 4063s as a "Strauss pair," low-passing the omni tracks to beef up the bass.

1) The bass response of the 4098 itself is much better than you would expect.  Where there has been a problem with the 4063 recording for any reason (like contacts needing rewiring), the 4098 recording is not bad on its own, way better than any miniature cardioid I tried before.

2) When worn in croakies the mic has directionality which is for me ideal; it cuts out much audience noise, but is not too narrow, picks up most of the forward area and brings things closer (not sure why that can be).

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Re: DPA 4098H miniature supercardioid
« Reply #15 on: August 09, 2013, 07:50:40 PM »
I'm not sure I understand why the rear ports wouldn't form a traditional chamber  ???  I suppose the diagphragm orientation is unusual in that respect, but it should work the same as the chamber creates the polar response.  Perhaps it has something to do with the timing of the front edge vs. rear edge of the diaphragm, rather than front vs. back as in a usual directional capsule.  I think that is what you are saying  ???

The capsule itself could be nearly identical although directional capsules usually have a lower resonant tuning.

I'm not sure yet, and it may not be evident from closer inspection tonight, but my current assumption has been that the diaphram is only exposed on it's front face, like all the miniature DPA omnis or any other omni with a small enclosed non-vented space (except for a atmospheric pin-hole vent) on the back side of the diaphram.   Since the rectangular diaphram housing is oriented sideways in the cylindrical capsule housing, it does not necessarily block passage around either side of it inside the tube like a traditional diaphragm.  That would mean the space inside the capsule housing would be open to both the interference tube end and the two small vents at the other, but exposing only the front face of the omni diaphram, which would measure pressure variations between the two ends. If on closer inspection I can see light coming through the capsule housing from the back vents around the rectangular diaphram housing then that should be the case. 

If its basically a traditional cardioid design, only folded up in a a bit, the diaphram should be exposed to the interference tube end on its front face, and the two rear vents on its back face.  If that's the case, I shouldn't see light coming around the housing.  That would make a lot more sense, and the more I think about it, the more I think that's probably the way it works.

That this mic appears to use an identical gold rectangular diaphram unit as the miniature DPA omnis, in what looks like an identical capsule housing expept for the rear vents most likey mislead me.

Anyway I drew up a couple quick sketches to explain what I meant, and drawing them is what help me sort out what I think is going on.  I now expect to see no light tonight!
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Re: DPA 4098H miniature supercardioid
« Reply #16 on: August 09, 2013, 07:55:15 PM »
I have been using these for several years..

Thanks for checking in here Jeff, your positive experience with these is what motivated me to give them a try.  It's just taken me much longer than I expected to get around to actually doing it.
« Last Edit: August 09, 2013, 07:57:11 PM by Gutbucket »
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Re: DPA 4098H miniature supercardioid
« Reply #17 on: August 09, 2013, 08:16:27 PM »
I'm not sure I understand why the rear ports wouldn't form a traditional chamber  ???  I suppose the diagphragm orientation is unusual in that respect, but it should work the same as the chamber creates the polar response.  Perhaps it has something to do with the timing of the front edge vs. rear edge of the diaphragm, rather than front vs. back as in a usual directional capsule.  I think that is what you are saying  ???

The capsule itself could be nearly identical although directional capsules usually have a lower resonant tuning.

I'm not sure yet, and it may not be evident from closer inspection tonight, but my current assumption has been that the diaphram is only exposed on it's front face, like all the miniature DPA omnis or any other omni with a small enclosed non-vented space (except for a atmospheric pin-hole vent) on the back side of the diaphram.   Since the rectangular diaphram housing is oriented sideways in the cylindrical capsule housing, it does not necessarily block passage around either side of it inside the tube like a traditional diaphragm.  That would mean the space inside the capsule housing would be open to both the interference tube end and the two small vents at the other, but exposing only the front face of the omni diaphram, which would measure pressure variations between the two ends. If on closer inspection I can see light coming through the capsule housing from the back vents around the rectangular diaphram housing then that should be the case. 

If its basically a traditional cardioid design, only folded up in a a bit, the diaphram should be exposed to the interference tube end on its front face, and the two rear vents on its back face.  If that's the case, I shouldn't see light coming around the housing.  That would make a lot more sense, and the more I think about it, the more I think that's probably the way it works.

That this mic appears to use an identical gold rectangular diaphram unit as the miniature DPA omnis, in what looks like an identical capsule housing expept for the rear vents most likey mislead me.

Anyway I drew up a couple quick sketches to explain what I meant, and drawing them is what help me sort out what I think is going on.  I now expect to see no light tonight!
There is another possibility I just thought of.. if you can redirect some of the pickup pattern from the front to the rear.... it's possible to turn a omni into a card the signal from the rear would be 180 degrees out of phase from the front if you could steer the sound from the back to the front. in theoretical terms atleast :) if anyone could pull this off it would be dpa. No need for a back vent on the capsule it self. the small vent is only that to equalize pressure on the diaphragm making it ok for high elevations would be my guess. this is in all dpa 4060 type capsules. this is my best guess.
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Re: DPA 4098H miniature supercardioid
« Reply #18 on: August 09, 2013, 11:15:35 PM »
These are freakin awesome bro ;D Are they wireless? Sorry, havent read the whole thread yet :) VERY TINY, and look amazing!!!

Bean

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Re: DPA 4098H miniature supercardioid
« Reply #19 on: August 10, 2013, 10:20:32 PM »
Hey Gut,

A little while ago I put together a spreadsheet to show the theoretical polar response of interference tubes.  We talked about it here: http://taperssection.com/index.php?topic=148194.msg1928020#msg1928020 
The response is calculated based only on the length of the tube.  By looking at your pics the tube looks like it's about 29mm long.  Below are plots of a 29mm interference tube's polar responses at different frequencies.  You can see that an interference tube of this length is only effective for frequencies above 4 kHz.  Comparing this graph to the polar plots you posted in your OP, you can see the directivity of this mic below 4k is dominated by the rear vents.

Note my plots are on a linear scale 0 - 1 while the DPA plots are in dB (0 to -25dB), but you get the idea.

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Re: DPA 4098H miniature supercardioid
« Reply #20 on: August 12, 2013, 12:09:28 PM »
Thanks MIQ, that's how I would expect it to work from what I know of interference tubes.

I think either design is possible and could work.  I don't think you necessarily need a diaphragm as a barrier in a chamber; that's just a convenient design to measure pressure.

Thanks Jon.  After thinking about this I realize you are correct.  Conceptually, phase reinforcement/cancellation due to differing acoustic path length differences could happen either on one side of the diaphragm or on opposite sides of it with the same end result.  I wonder if I'm missing something in regards to the practical realization of that however.  Are you or is anyone here aware of a manufacturer who uses closed back omni capsules in specially designed acoustic housings to produce directional mics? By that I mean rear vented housings, not simply putting an interference tube in front.  Assuming it can be made to work equivalently, I would think the higher diaphram tension of the omni element would be benefitial in providing reduced handling noise at least.


On closer inspection over the weekend with a bright light and reading glasses, it is apparent that the capsule housing surrounding the gold diaphram unit is filled with epoxy or some other material.   There is no internal acoustic path around the retangular gold eletret diaphragm housing inside the external mic housing.  That doesn't shed light on what is happening inside and/or under the eletret housing, but I'm guessing this thing works as a normal cardioid with repect to the rear vents.

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Re: DPA 4098H miniature supercardioid
« Reply #21 on: August 12, 2013, 12:42:53 PM »
Thanks MIQ, that's how I would expect it to work from what I know of interference tubes.

I think either design is possible and could work.  I don't think you necessarily need a diaphragm as a barrier in a chamber; that's just a convenient design to measure pressure.

Thanks Jon.  After thinking about this I realize you are correct.  Conceptually, phase reinforcement/cancellation due to differing acoustic path length differences could happen either on one side of the diaphragm or on opposite sides of it with the same end result.  I wonder if I'm missing something in regards to the practical realization of that however.  Are you or is anyone here aware of a manufacturer who uses closed back omni capsules in specially designed acoustic housings to produce directional mics? By that I mean rear vented housings, not simply putting an interference tube in front.  Assuming it can be made to work equivalently, I would think the higher diaphram tension of the omni element would be benefitial in providing reduced handling noise at least.


On closer inspection over the weekend with a bright light and reading glasses, it is apparent that the capsule housing surrounding the gold diaphram unit is filled with epoxy or some other material.   There is no internal acoustic path around the retangular gold eletret diaphragm housing inside the external mic housing.  That doesn't shed light on what is happening inside and/or under the eletret housing, but I'm guessing this thing works as a normal cardioid with repect to the rear vents.

The other possibility.. Another capsule inside the rear vent.
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Re: DPA 4098H miniature supercardioid
« Reply #22 on: August 12, 2013, 06:52:58 PM »
Chris- Like you mention, a second capsule would be another way to manipulate the pickup pattern, yet in this case I can't see how another capsule could fit into a standard 406x omni housing with a couple vents on the back side of it.


Jon- Actually I do think of a cardioid as a being a modified figure-8, but I'm a 'basic-principles' mechanical design minded guy.   I'm getting off topic here, but an aspect I don't understand is how that modification is physically implemented in real-world microphones to produce directional patterns which are as uniform as possible across a broad frequency range and not just peaking as a bell shaped curve, centered around a single frequency. That's the microphone 'black-art' stuff I guess.  All the basic explanations and simplified conceptual illustrations I've come across just show a single pathlength/wavelength arriving at the front of the diaphragm and another arriving at the back of the diaphragm with a phase relationship that varies between the two with source angle, and that seems to me like it would be very frequency specific.
 
Regardless of how that works in real implementations, I speculate a compelling motivation for a manufacturer to use an omni capsule in a directional microphone design would be manufacturing and production related issues, such as using an already developed and well regarded omni capsule that is in full production, minimizing need for additional capsule fabrication and inventory overhead for a new microphone design.  I understand what you are saying on the need to increase the housing diameter to provide a path around the diaphragm inside the housing for a given diaphragm diameter.

Thanks for the 'ah-hah' moment in realizing that the two possibilities I sketched previously are more or less conceptually the same in regards to the path-length phase cancellation/reinforcement.  Actually, looking at it again and excluding the interference tube, I realize a pathlength based directional design using an omni element would require an inverted signal relationship between the two paths compared to a typical design.  In a design with both sides of the diaphragm exposed to signal, identical path-lengths produce identical pressures on each side of the diaphragm, canceling each other and producing a null.  When that interaction happens on one side of the diaphragm only, identical path-lengths instead reinforce one another and produce a maxima.  A reverse polarity signal is required to cancel pressure if the two paths meet on the same side of the diaphragm.
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Offline DSatz

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Re: DPA 4098H miniature supercardioid
« Reply #23 on: August 15, 2013, 12:18:57 AM »
Just wanted to point out something about the frequency response graphs near the top of this thread: The low-frequency response is nearly flat at 20 cm, while at 100 cm measurement distance, the response is roughly 12 dB down at 50 Hz. This response profile indicates a close-speech microphone, not a general-purpose studio microphone.

There is still some proximity effect at 100 cm (= 1 meter), so the low-frequency response to be expected for sound sources farther away than 1 meter would actually be even a little less than the lowest curve shown.

DPA should be commended for publishing this detailed information, which they haven't generally done in the past. Instead, the published curves for their directional microphones (going all the way back to their earliest cardioids) have generally been corrected for a 30 cm pickup distance--a fact which you could read in the fine print if you chose to look for it.

Meanwhile, however, the other leading microphone manufacturers (Neumann, Schoeps and others) generally correct their frequency response measurements of directional microphones for a 1 meter (= 100 cm) measurement distance. Obviously that makes a rather large difference in the results--in this case, about 8 dB at the bottom of the frequency range--and that should be considered when comparing the response curves for DPA directional microphones against those of most other leading manufacturers.

--best regards

A clarifying P.S., I hope: As far as I'm concerned DPA can print any curves they want, as long as they specify their measurement conditions. Quite possibly their studio microphones are typically used at ~30 cm distances; if so, their published curves would indicate something like the actual performance of their microphones in that application, and I think that's ample justification.

But people who need directional microphones for more distant pickup should realize that they won't be getting anything like the low-frequency response shown in the 30 cm curves. And people certainly shouldn't compare 30 cm curves to 1 meter curves no matter what application they have in mind.
« Last Edit: August 15, 2013, 12:32:31 AM by DSatz »
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Offline Len Moskowitz (Core Sound)

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Re: DPA 4098H miniature supercardioid
« Reply #24 on: August 15, 2013, 07:34:38 AM »
It's probably worth noting this real clearly for the newbies:

At normal recording distances these specific capsules have poor bass response. The second graph shows that clearly: 100cm is only ~39-inches.

So these capsules are not well-suited for recording concerts from the audience unless you plan to add lots of EQ in post-production, or as Gutbucket plans, using them in an array with other mics.
« Last Edit: August 15, 2013, 07:48:42 AM by Len Moskowitz (Core Sound) »
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Re: DPA 4098H miniature supercardioid
« Reply #25 on: August 15, 2013, 11:56:08 AM »
Thanks for the clarifications gentlemen.

None of the DPA miniature directional mics are really designed for recording at a distance.  DPA targets the 4089H for hanging choir microphone applications.  I assume that the typical intended installation would place these microphones somewhat farther than 100cm from the source, probably using a number of these in an A-B spaced line configuration ~3-5 meters from the choir members.  Not being much of a choir recordist I assume it may be common practice to high-pass choir mics for PA reinforcement applications, making the falling low frequency response of these somewhat pre-tailored to the indented application.

Below is the frequency response graph for the DPA 4081 miniature supercardioid, designed for close, on-instrument mic'ing.  The polar is identical to the one I posted earlier for the 4098.  The on and off-axis frequency response graphs appears mostly identical to the 4098 except for a slightly more rolled response above 10kHz.  It appears to be a very similar microphone, except for a different mounting configuration and lower sensitivity (6mV/Pa for the 4081 compared to 20 mV/Pa for the 4098, which is the same sensitivity difference as the 4061 compared to the 4060 omni).  The 4098 is the only DPA miniature with a posted proximity graph, there is no proximity effect graph posted for the 4081 or the 4080.  DPA's other miniature directional is the 4080, which the same sensitivity as the 4081 but a contoured response tailored for lavaliere-mounted speech applications and is probably even less applicable to recording music from a distance.

DPA 4081-




And here’s the 4098H again for comparison-





« Last Edit: August 15, 2013, 11:59:21 AM by Gutbucket »
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Online WiFiJeff

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Re: DPA 4098H miniature supercardioid
« Reply #26 on: August 15, 2013, 06:53:17 PM »
I actually have the 4099s, which are also lower sensitivity 6V/Pa mics like the 4061 and 4081.  The 4098 came out later.  But I have not had any problems using it (although I am quite partial to the 4060s) on even rather quiet acoustic music.  PM me for a sample on some baroque theorbo and string music.

Jeff

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Re: DPA 4098H miniature supercardioid
« Reply #27 on: November 05, 2013, 03:56:51 PM »
Anyone have ideas for finding an appropriate larger foam windscreen for use on these outdoors?

I called Shane at DPA USA yesterday and he had no suggestions, and said he had not heard reports from anyone using them outdoors yet.  I need to find something pretty quickly for use in about a week.

The portion which the screen needs to slip over is ~1-1/2" long X 7/32" in diameter (or just under 1/4").
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Re: DPA 4098H miniature supercardioid
« Reply #28 on: November 05, 2013, 04:03:44 PM »
Anyone have ideas for finding an appropriate larger foam windscreen for use on these outdoors?

I called Shane at DPA USA yesterday and he had no suggestions, and said he had not heard reports from anyone using them outdoors yet.  I need to find something pretty quickly for use in about a week.

The portion which the screen needs to slip over is ~1-1/2" long X 7/32" in diameter (or just under 1/4").
My dead rats. BTW did you get my email?
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Re: DPA 4098H miniature supercardioid
« Reply #29 on: November 05, 2013, 04:25:55 PM »
I'll need them sooner than your's would get here.  I have the material to whip up a couple rats and likely will do so this weekend, but the foam of the existing screens is very thin, even for only playing the role of under-fur spacing.  It's wall thickness is only like 3/32".  I did one outside test recording of some music about a month ago with just the existing foam screens and just a rather-slight occassional breeze produced audible rumble.   I suspect I'll need some thicker foam for effective use of the rats.

Thanks for the heads up on the email, haven't been on-line that much over the past week.
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Re: DPA 4098H miniature supercardioid
« Reply #30 on: November 05, 2013, 05:29:36 PM »
I'll need them sooner than your's would get here.  I have the material to whip up a couple rats and likely will do so this weekend, but the foam of the existing screens is very thin, even for only playing the role of under-fur spacing.  It's wall thickness is only like 3/32".  I did one outside test recording of some music about a month ago with just the existing foam screens and just a rather-slight occassional breeze produced audible rumble.   I suspect I'll need some thicker foam for effective use of the rats.

Thanks for the heads up on the email, haven't been on-line that much over the past week.
I donno if you ad rats to the mix you will get a huge reduction is wind. Even if your mics windscreens are not "great" I have some long windscreens here. When I finish the other project up for you I will send you a pair to check out. If you like them I will order more.

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Re: DPA 4098H miniature supercardioid
« Reply #31 on: November 05, 2013, 06:08:29 PM »
Thanks.  I'll probably simply stitch up some rats for the existing thin foams to get me through the Bear Creek festival next week (an event I configure a special rig for which is a primary motivation for giving these mics a try).  Might cut up some other foams I have laying around to get additional airspace under the rats if I can find something appropriate and do it cleanly.

Checked the Windtech and Rycote sites and found a Rycote "mini-softie" foam/fur combo (listed as 4cm mini softie #033003) specifically for the 4098.  Checking a few vendors websites, none had that part listed, but the "mini-softies" for larger mics are all about $120 each or more.  Significantly more than I'm willing to invest for this.  They make quality stuff and I'm sure they fit and work well, but I was rather shocked to find mini foam/furs can command that kind of coin.
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Re: DPA 4098H miniature supercardioid
« Reply #32 on: November 05, 2013, 06:21:13 PM »
I bet that one of the Audio-Technica windscreens made for their unipoint or slimline mics would work.

Something like this:
http://eu.audio-technica.com/en/products/product.asp?catID=6&subID=48&prodID=3069


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Re: DPA 4098H miniature supercardioid
« Reply #33 on: November 06, 2013, 12:14:45 PM »
Thanks, I'll look into that.
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Re: DPA 4098H miniature supercardioid
« Reply #34 on: November 21, 2013, 12:11:08 PM »
Ran out of time to order the appropriate real foam windscreens, but foam hair curler inserts repurposed as windscreens worked well last weekend on my first real use of these mics other than a couple test recordings.   Bought a pack of 8 for a buck at the dollar store across the street and stuffed a couple of them in my ears as a quick high frequency reduction check.  They seemed about as transparent as my other 'real' foam windscreens.  I sprayed them with some silicone water repellant I was treating other camp gear with as well.  The overall dimensions were perfect and the hole through the center of the foam cylinder fit snuggly over the small diameter mic and interference tube.  The breeze outside at the event was mild (the HVAC at an inside location I also recorded at actually blew harder and directly on them). So this was no heavy windstorm test and I didn't get around to cutting a small plug of foam from one of the extras to fill the hole exit out the front of the foam cylinder, but that didn't seem to matter.

The flexibility of the attached gooseneck was really nice for correctly orienting them and providing some impact protection.
« Last Edit: November 21, 2013, 12:13:29 PM by Gutbucket »
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Offline Jamos

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Re: DPA 4098H miniature supercardioid
« Reply #35 on: November 25, 2013, 01:39:54 PM »
That's an awesome rig you have there…
You must need to stake or sandbag the base of the stand?  Especially outside, I'd imagine it could take flight.

How did the recording come out?

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Re: DPA 4098H miniature supercardioid
« Reply #36 on: November 26, 2013, 06:04:12 PM »
It's designed to be super mobile rather than staked or bagged in place and must definitely remain attended and not left alone in a crowd. The small bag with preamps, recorder and batteries hangs between the stand legs directly below the vertical tube for a central and lowered center of gravity, which helps with stability.  That keeps it quite stable if not accidentally knocked or grabbed.  I can grab the stand with one hand with its telescopic arms fully deployed and move it searching for the sweet spot.. or if I need to move it away quickly.  If moving it very far (like to a different performance stage) I'll retract and fold the arms to make it more manageable navigating through a crowd.

The recordings sound quite promising on direct multi-channel playback of the raw files. I haven't had a chance to edit anything yet or do any 2-channel down-mixes, but I expect that to work well since it has previously using other cards or supercards in the same rig before trying the 4098s. 

That rig is spaced 4061 omnis > CA-UGLY > DR2d (line input) as Left / Right channels,
and the 4098 supercards > MMA6000 > DR2d (mic input) as center / back channels.

I'll work on getting some samples up for anyone interested when I get a chance.
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Re: DPA 4098H miniature supercardioid
« Reply #37 on: May 05, 2015, 02:14:39 PM »
Update on the search for appropriate outdoor windscreens for the 4098H-

The dual-layer Audix WS1281 foam windscreen was suggested as a possible fit, but it's bore was not deep enough to fit the length of this mic with it's miniature interference tube.  However, by removing the smaller foam insert and replacing that with the make-shift hair-culer foam screens, the screens fit the mics very well and and seem as if they will provide sufficient protection for reasonable outdoor conditions without too much wind.  I'd used the big dual-layer foam Shure screens with the hair-curler foams inside the same way, which provided good wind protection, but was too heavy for the microphone's integral flexible goose-neck to support without drooping.

Details and more photos can be found over in the oddball thread- http://taperssection.com/index.php?topic=96009.msg2141441#msg2141441

Here's a few from there which sum it up-





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Re: DPA 4098H miniature supercardioid
« Reply #38 on: May 05, 2015, 09:34:17 PM »
I love the section...........Hair curler foam inserts...  we are an ingenious group of mofos.  LOL

peace ook
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Re: DPA 4098H miniature supercardioid
« Reply #39 on: June 16, 2017, 04:32:28 PM »
Found this video on DPA's miniature microphone tech on their website-
DPA webinar: Miniature Microphone Technology https://youtu.be/SEtfvq1RhDw

Details on the miniature pressure omni series- 4060/61/62/63 as well as the miniature pressure gradient mics- 4080/98/99, including info on the miniature interference tubes these mics use, confirming much of what we speculated about earlier in this thread.
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Offline 108 Ohms

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Re: DPA 4098H miniature supercardioid
« Reply #40 on: June 16, 2017, 09:53:14 PM »
Any good samples to be listen to from section of a Saenger sized theater?

I wonder what these could do in a typical noisey bar.    :hmmm:
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Re: DPA 4098H miniature supercardioid
« Reply #41 on: June 19, 2017, 09:46:56 AM »
Not familiar with the Saenger.  Most of what I have with them in is my oddball 4 or 6 channel rig in combination with omnis, most of that outdoors.  I did do a couple straight near-spaced stereo config recordings with them early on that I'll try and dig up.  One was a comp with them in the same setup as a MG210 pair as I recall - Galactic at Revolution Live in Ft Lauderdale I think - which is sort of a medium sized club / larger bar, with typical bar noise and talking.
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Re: DPA 4098H miniature supercardioid
« Reply #42 on: June 19, 2017, 06:11:26 PM »
^ I'd love to hear that comp, if you can find it!

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Re: DPA 4098H miniature supercardioid
« Reply #43 on: June 19, 2017, 07:05:43 PM »
I'll take a look.  Unfortunately much of my storage is offline currently. 

I do remember my personal take away, which was this-
The reduced bass sensitivity of the 4098 at a distance actually worked better than I though it would in that particular room to tame overly active subs.  I was able to EQ things to where I was happy with the recording using just those two mics, which is always one of my primary litmus tests.  After bass EQ, these were still somewhat brighter overall than the MG210 pair, but not in a way which was shrill or out of control.  Again, being manageable to achieve the tonal balance I was happy with without EQ frustrations.  On the more subtle attributes, the Gefells remained unmatched for overall imaging smoothness and apparent depth perception (image depth, noticing front/back dimensional layering).  The Gefells remain my reference cards and supercards.  If I was using single stereo pairs, that difference would be more persuasive to me in many situations, but certainly not all.  The way I'm using them in my multi-channel arrays that difference becomes more or less mute, and I don't think at all about a reduction in quality substituting them for the Geffs in those multichannel arrays, only about the reduction in size, weight, cost, and a greatly reduced vulnerability to dampness and foul weather.

Hope that helps.
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