Topic: Countryman Isomax-2 side-addressed miniature microphones?

[Gutbucket]

Anyone here have experience with these?  Richard?

Here's the data sheet-
http://www.countryman.com/download/ISOMAX%202%20All-Purpose%20datasheet.pdf

Specs and smoothed polars look decent, how does it sound?  Respose graph is listed as measured at 6" so I'm sure the directional ones shelve down significantly below about 500Hz like most non-omni miniatures.

I assume the directional models have a screen or opening of some sort on the back surface of the mic housing which must be left open, meaning they cannot be taped down to a flat surface, is that correct?

Data sheet states "Available in all directional patterns including omnidirectional, cardioid, hypercardioid, and bidirectional/Figure 8"
There is no specific data on the figure-8 on the datasheet or mention of it on the webpage.

[illconditioned]

I had access to a pair of these (cardioids?) a while back.  I was asked to wire them for plug in power, but did not have enough time to investigate, so I sent them back to the owner.

My impression is that they sounded a bit "thin", likely that was the bass rolloff.  I have not tried the omni, but I expect it to sound similar to the Tram mic, made by Lectrosonics.  These (the Tram) are good mics, and I have used them for concert recordings, but I think the B3 is better.

One thing that occurred to me is to take these mics and do processing to "return" the Bass response.  Maybe not all of it, but enough to make it sound real again. If you could do this, it would make a killer stealth setup.  However, for now my recording focus is either on Omnis (B3) or Sennheiser MKE40, which in my opinion, are the best small (ie. 10mm) cardioid out there (at least without requiring processing in post to bring the bass back).

If someone wants to loan and/or trade me a pair of these, I would be willing to experiment again.  There are also the Countryman H6D,E6D (2.5mm ear/headset mic, 24dBA self noise) and B2D (2.5mm "cheek" mic, 36dBA self noise) that may be worth trying.  I know the bass rolls off quickly, but I would still like to see the polar pattern at different frequencies.  They only show 1kHz.

Hmm.  Looking at the spec sheet, the polar patterns vs. frequency look great.  Maybe it is worth trying out a pair of these.  I expect sound quality similar to what I've got on my webpage (see RTI1200A).  That is the cap inside the TRAM mic.

  Richard

[acidjack]

If those are the same mics used to record a bunch of Pearl Jam shows back in the 90s (and I'm pretty sure they are) I think Richard's assessment of "thin-ness" is correct.  IIRC I never cared for them, but I suppose it depends on the application.  You generally record in more ideal conditions than "mics on hat in the back of a soccer stadium" which was the more common usage I'm familiar with them in...

[Gutbucket]

The nice looking polar response and the side-adress config is part of what intrigues me for a specific multichannel setup I have in mind.  I'm not at all averse to needing to do some EQ correction as long as doing so produces good quality results.  Correct in that they would be used in more ideal recording situations in good rooms.

The capsule format and housing does look like the Tram (which I've never used) and also a different miniature omni I had back in the late 80's (can't recall the make, but it wasn't Tram)

Richard, do you recall if there was any vent on the back surface of the housing?

I might want to give these a try, more research first..
If anyone else has experience with them, please let me know.

[illconditioned]

The nice looking polar response and the side-adress config is part of what intrigues me for a specific multichannel setup I have in mind.  I'm not at all averse to needing to do some EQ correction as long as doing so produces good quality results.  Correct in that they would be used in more ideal recording situations in good rooms.

The capsule format and housing does look like the Tram (which I've never used) and also a different miniature omni I had back in the late 80's (can't recall the make, but it wasn't Tram)

Richard, do you recall if there was any vent on the back surface of the housing?

I might want to give these a try, more research first..
If anyone else has experience with them, please let me know.

Yes, there is a vent in the back.

They could be good for ambisonic or other configurations. The good news is they are (probably) well matched.  But remember that the sound will only be as good as the capsules you use, and if you're expecting DPA406x or B3 quality, you might be disappointed.  Therefore I suggest trying to "audition" a single or pair of them first.

By the way, please let me know if you unload some B3's, or if you see more forsale.  I'm looking for another pair .

  Richard

[Gutbucket]

I'm holding on to the B3s I have but I'll let you know if I come across good deals on more of them.  I do need some flat non-boost grids for mine, best source for those?

Yes, 4060/B3 quality is the target, even if I need some EQ to get there (if they 'take EQ' well enough).  So I'm less concerned about the raw sound of their direct output then the ability to cleanly and easily manipulate what frequency balance they have.  Not all mics have good flexibilty in allowing that, but the ones that interest me most do.  I'm not sure if its smooth non-resonant response, sufficient dynamic range or both which make doing that more attractive with some mics and not so much with others.  In contrast, I can do nothing afterwards to modify a mic's self-noise, pattern consistancy or dynamic range.  The configs I have in mind would use these in combination with either 4060 or B3 omnis so that should help as well with overall frequency balance. 

Thanks for the confirmation on the vent. I had assumed they have a vent of some sort to achieve the pattern, and the data sheet mentions stereo mic'ing a piano under the lid by arranging two of the directional capsules back to back with an open 1/8" spacing between them. 

I didn't even think of the ambisonic angle, but you are right, if the polar pattern is as accurate as the plots indicate, and a 1/8" spacing behind is enough, then an amazingly compact tetrahedral array of four cardioids should be possible and would have a closer capsule spacing than any available ambisonic mic, and therefore produce output patterns which remain accurate to a higher frequency than the others.  Like you say, other constraints come into play too.  I think the Tetramic is pattern accurate up to about 10kHz or so with it's capsule spacing (which in a practical sense may be plenty for music recorording, if not insect or bat call research).  Although it's high frequency response doesn't stop there, the derived polar patterns above that frequency become erratic.

[illconditioned]

I'm holding on to the B3s I have but I'll let you know if I come across good deals on more of them.  I do need some flat non-boost grids for mine, best source for those?

Yes, 4060/B3 quality is the target, even if I need some EQ to get there (if they 'take EQ' well enough).  So I'm less concerned about the raw sound of their direct output then the ability to cleanly and easily manipulate what frequency balance they have.  Not all mics have good flexibilty in allowing that, but the ones that interest me most do.  I'm not sure if its smooth non-resonant response, sufficient dynamic range or both which make doing that more attractive with some mics and not so much with others.  In contrast, I can do nothing afterwards to modify a mic's self-noise, pattern consistancy or dynamic range.  The configs I have in mind would use these in combination with either 4060 or B3 omnis so that should help as well with overall frequency balance. 

Thanks for the confirmation on the vent. I had assumed they have a vent of some sort to achieve the pattern, and the data sheet mentions stereo mic'ing a piano under the lid by arranging two of the directional capsules back to back with an open 1/8" spacing between them. 

I didn't even think of the ambisonic angle, but you are right, if the polar pattern is as accurate as the plots indicate, and a 1/8" spacing behind is enough, then an amazingly compact tetrahedral array of four cardioids should be possible and would have a closer capsule spacing than any available ambisonic mic, and therefore produce output patterns which remain accurate to a higher frequency than the others.  Like you say, other constraints come into play too.  I think the Tetramic is pattern accurate up to about 10kHz or so with it's capsule spacing (which in a practical sense may be plenty for music recorording, if not insect or bat call research).  Although it's high frequency response doesn't stop there, the derived polar patterns above that frequency become erratic.

The Isomax might be good for ambisonic.  But the question comes down to how good are the capsules.  That is why I suspect the Tetramic... unless i know the capsules are in there.  I would want to test the capsules first in a stereo pair in an optimal position, hopefully something challening, like close up jazz or classical music.  If they sound great, then move forward with an ambisonic, "bug eyes", or other setup...

  Richard

[SmokinJoe]

I have used Earthworks cards and hypercards quite a bit.  They are similarly designed for "close micing" with a roll off to compensate for the proximity effect.  I went through a time when I used them as my primary room mics and found it hit or miss.  If it's a boomy situation, they are clean when other mics are mud, but frequently the tapes sounded thin.  I was never very successful trying to boost the low end back to "normal" levels.  That was a few years ago, and probably I just didn't know what I was doing with EQ in post, but I came to the conclusion that if the curve is down a lot, like 20db, trying to boost that back approaches simple math... 0 x 1000 = 0.

I would expect the same situation here.