Microphones with the Tympan

#1

The Tympan includes microphones on its circuit board, but you can also use external microphones via its headphone jack or via its “line-in” through-holes. I’ve calibrated three microphones so far.

  • Sony ECM-CS10, which is a lapel microphone
  • Knowles SPH1642, which are the mics on the Tympan PCB)
  • Knowles EK-23024, which is a hearing aid microphone.

The results of my calibration of these three mics are shown below.

You can see how I did the calibration here: http://openaudio.blogspot.com/2017/05/calibrating-microphones-with-tympan.html

What other kinds of microphones are interesting to people?

Chip

#2

Hello,
Congratulations for your beautiful work neat … :slight_smile: I would like to learn to know this type of DSP. I believe the TLV320AIC3206IRSBT will soon be obsolete and officially re-introduced by TLV320AIC3256IRSBT.
Besides, I would like to order only a Tympany Teensy card. It’s possible?

#3

Looking at the TI website, I do not see any message about the 3206 being obsoleted. Comparing specs with the 3256, they appear to be very similar in performance, though the 3256 is more expensive ($4.45 @ 1000 vs $2.75 @ 1000).

Do you have experience with the 3256 vs the 3206? Do you like it better?

Chip

#4

A message from Texas Instruments warns us not to use this chip for the next studies when I wanted to make a printed circuit for your Tympan project because it cost 250 dollars (at the beginning and 150 dollars after. :slight_smile: ), plus 140 dollars’ for USPS and French customs duties. :frowning:
By the way Texas Instruments no longer manufactures this version of chip but it is still in stock.
That is why, for the next prototypes, we could use the 3256

#5

Wow. I can’t believe that USPS plus French customs was a $140. Ouch! So sorry!

#6

trade with USA is very expensive! But sometimes products come from USA avoiding customs!

#7

I’ve done more measurements of microphones with the Tympan. Specifically, I looked at the self-noise using different microphones. The choice of microphone definitely matters!

Details: http://openaudio.blogspot.com/2018/08/microphone-self-noise.html

TympanC-calibrated

In these results, I show two microphones with the Tympan: a Sony lapel microphone and the Tympan’s built-in PCB microphones. I also show a laboratory-grade microphone (B&K) through its own recorder just for reference.

As you can see, the Tympan’s built-in PCB microphones are definitely quieter than the particular Sony lapel microphone that I tried. So, if you’re using your own external microphone with the Tympan, be careful and be sure to pick a quiet one!

Chip