Cheapest Calibrated Mic Ever

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Parts Express sells its iMM-6 calibrated Mic for $16.25. But there is a catch. It is designed to be used on iPhones and Android phones, not on a PC. That prevents us from using our favorite PC software with the mic. So, it seems this is a perfect item to hack. That is what this thread is about.

Here are pics of the mic:

From the business end:

An externally hosted image should be here but it was not working when we last tested it.


And a profile:

An externally hosted image should be here but it was not working when we last tested it.


If anyone knows how to use this mic with a PC, please let us know.

I think that to make the best use of this mic requires hacking it. There are issues of course. Here are some. If you have more, please post.

One issue is that the plug is a TRRS (tip, ring, ring, sleeve) plug rather than a TRS (tip, ring, sleeve) plug as used in PC sound cards. So we need a schematic of what is going on inside the mic. I have been unable to find one. Anybody out there got the schematic?

Another issue is whether any phantom power is being delivered to the mic. PE claims it is a condenser mic. If so, power is required. This might be resolved with a schematic. Does anyone know details re: the phantom power issue and how to resolve it with a PC?

Another issue is the shape of the mic. I presume that the capsules are calibrated in their sub-carrier before the sub-carrier is placed in the frame holding the headphone/line out jack. So, the mic will be more closely calibrated with its curve if the jack and its related plastic is removed. Thoughts?

Another issue is whether the calibration curve was measured with 0 deg, 90 deg or 45 deg mic position relative to the sound source. My guess is it was done at 0 deg. Any ideas?

I think this hack would be a fun project and result in an impressive calibrated mic for very little cash.

What do you think?
 
the TRRS was made for the smartphone use. Meaning is here also, that (in the other "leg" from the microphone), there is another TRS jack for headphones).

arrangement is like this, from tip to sleeve (ground). tip = left, Ring 1 = right, Ring2 = mic, sleeve = common ground.

so you basically only need the second ring and sleeve for the mic only connector. The others, are just for the headphones. Make yourself an adapter cable, from a TS minijack to a TRRS female minijack (you can find those). It's important that the female part is TRRS, since the 2 connections we'd be using, both would be on the common connector area of a TS jack (sleeve). On the male part, you can use whatever you need, just remember that the tip will be the mic connector, and the other 3 (if you're using a TRRS) are connected to ground.

Then: phantom power: those mics are, just like lavaliers for ENG use, and most microphones for pc use, electret's, most likely 1,5V 'phantom power will do the job.
PC's also deliver the same voltage for most mic's... so you can just use them if you make a new adapter for the TRRS jack :)

regards,
Bert.
 
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This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.