Topic: Zoom’s 32-bit float m/s - Instamic Pro Plus C

[grawk]

Looking at it, the face opposite th clip is on axis.

[datbrad]

There are 4 openings on one end, and the stereo version adds two on the sides for the MEMS microphones. In other words, if you had no clip and set it on a table, on-axis would be running parallel to the tabletop.

[Craig T]

I know, but what is "on axis" for this device?  Wondering how best to wear/mount the stereo unit.

what is "on axis"?

Sound arriving from the direction that the center of the diaphragm is "pointed" at.

[Gutbucket]

Primary on-axis will be directly in front of the four holes for the MEMS on the front of the unit.  Assuming the device is lying flat on a table, directly above and below that probably won't make much difference, because the "height" of the MEMS and front face of the unit is small in that dimension.  The potentially audible attenuation of highest frequencies will occur when the source is positioned off-axis over to either either side (where the additional MEMS are located) because the MEMS across the front form a longer line along that axis and the body of the unit is significantly wider in that dimension.  ..and around the back of the unit.

Dunno if any of this will be audible or not.  Just speculating based on the fundamental acoustics of a line arrangement of sensors and the geometry of the unit.  It might like orienting miniature omnis in our use cases.  I can hear the tiny bit of highest frequency attenuation off-axis when playing around with the DPA miniature omnis, but found long ago that in actual use recording musical performances their orientation doesn't really matter much.

[Gutbucket]

Its the same phenomena that causes the polar pattern to narrow at high frequencies in relation to the size and shape of the diaphragm.  A larger diaphragm/housing will cause the polar pattern to begin to narrow on-axis at a somewhat lower frequency than a smaller diaphragm/housing.  A rectangular diaphragm mic such as in Pearl/Milab mics will have a narrower HF pattern along the long axis of the diaphragm than along the short axis.  Same for a longish ribbon mics, which produce a wider HF fig-8 pattern in the horizontal axis and a narrower fig-8 in the vertical axis.

[Craig T]

I'd like to clip this to my chest.  Would that have it pointed up towards my face?

[Gutbucket]

Yes. Use as a lavalier mic clipped to the talent's shirt that way is surely the primary intended use for these things.  But as mentioned, its likely there will be little difference for sound arrival from above or below (when sitting flat on a table), or in your case from out in front (when clipped to a shirt with the it's primary axis facing upward)

[papabliss]

For stealth mode, I'm going to use double sided tape and put it on top of my bald head and wear a cap. 

[Gutbucket]

Yes. Use as a lavalier mic clipped to the talent's shirt that way is surely the primary intended use for these things.  But as mentioned, its likely there will be little difference for sound arrival from above or below (when sitting flat on a table), or in your case from out in front (when clipped to a shirt with the it's primary axis facing upward)

Let's see, the unit is 1/2" thick, call that ~1.3 cm.  Frequencies over 15kHz should refract around that probably higher.  And it's rounded, so unlikely to notice that effect on sound pickup from the front when clipped to a shirt with the primary axis facing upwards..  Unless you sneeze, exclaim or breathe heavy! 

[Gutbucket]

For stealth mode, I'm going to use double sided tape and put it on top of my bald head and wear a cap. 

Eminently doable!  It's smaller than I realized @ 1.5" X 1" X 0.5"  Need to figure out how I might put one over each ear, one at front of forehead and one in back.  Say, inside a snake-skin hat-band!

"Those lumps? Mice"

[Craig T]

For stealth mode, I'm going to use double sided tape and put it on top of my bald head and wear a cap. 

There is a magnetic mount option if you happen to have a steel plate in your head.

[Craig T]

I grabbed a stereo unit.  Will report back.

[datbrad]

This is the hat I use to run a pair of these. Works great. This is the mfg link, but you can get it from Amazon also.

https://www.chalktalksports.com/products/cool-run-pocket-hat-for-runners-black

[Gutbucket]

You put them inside those side pockets? ..and the fabric is sufficiently audibly transparent that it doesn't sound muffled?

[papabliss]

You put them inside those side pockets? ..and the fabric is sufficiently audibly transparent that it doesn't sound muffled?

The Head and the Heart show Brad shared sounded good.