When it comes to using studio mics for ultrasonic recording - and especially for outdoor nature recording - then I think the Sennheiser MKH8020 would probably be hard to beat ? .....? Extended upper FR to at least 70KHz, and a lot more linear than other mics I've seen recommended for ultrasonics.?
Plus the advantage of 'low Z' RF technology for resistance to outdoor moisture problems.
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The only downside for amateurs like me is the price!?
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On Sat, Dec 28, 2024 at 01:44 PM, Jerry Lee Marcel wrote:
Actually it depends very much on what one expects.
I've done some experiments with ultrasonic response of typical studio mics.
Using cymbals as the source, one finds out there is significant energy detected by many SDC's up to 60kHz. Of course it doesn't really indicate linearity, but the spectrum shows that the actual response goes quite high.
I think the preferred source for ultrasonic measurements is still a spark gap.
Le 28/12/2024 à 12:48, Arjay1949 a écrit?:
On Fri, Dec 27, 2024 at 08:01 PM, Richard Lee wrote:
I've measured up to 40k on the electret mics that i'm using, which is very nice. but I want more.
How do you measure mikes up to 40kHz?
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I too would be interested to learn how soundwichartist makes the appropriate measurements.....?
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I have found that measuring the detailed ultrasonic response of mic caspules is not an easy task, without access to some serious scientific equipment.
The published ultrasonic responses for cheap capsules - like Knowles MEMs and electrets - show a pretty erratic response (See Knowles App note here: )? ?
Even the expensive Sanken? CO-100k model mentioned earlier has a very non-linear HF response (see here: ).
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I've found applying the ultrasonic output from a suitable generator directly to a piezo audio 'tweeter' - like this one: ? - can give a rough idea of the ultrasonic response of a capsule......
Sadly of course the linearity of that type of transducer at ulrasonic frequencies introduces another unknown to the proceedings!
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The published ultrasonic response for the Knowles MEMs capsules can be quite useful.
I find a complex response curve like that easier to correct digitally - in post - than it would be trying to build an accurate hardware analogue filter to compensate.
