https://github.com/pandermusubi/umik-1
🎙️ Extended calibration files for omni-directional USB measurement microphone UMIK-1
https://github.com/pandermusubi/umik-1
Last synced: over 1 year ago
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🎙️ Extended calibration files for omni-directional USB measurement microphone UMIK-1
- Host: GitHub
- URL: https://github.com/pandermusubi/umik-1
- Owner: PanderMusubi
- Created: 2014-12-20T14:46:27.000Z (over 11 years ago)
- Default Branch: master
- Last Pushed: 2022-05-17T08:26:41.000Z (about 4 years ago)
- Last Synced: 2025-01-27T09:12:09.120Z (over 1 year ago)
- Language: Gnuplot
- Homepage: https://www.minidsp.com/products/acoustic-measurement/umik-1
- Size: 65 MB
- Stars: 10
- Watchers: 3
- Forks: 3
- Open Issues: 1
-
Metadata Files:
- Readme: README.md
Awesome Lists containing this project
README
# UMIK-1
Documentation and custom software for calibrated omni-directional USB measurement
microphone [UMIK-1](https://minidsp.com/products/acoustic-measurement/umik-1)
from [miniDSP](https://minidsp.com) are offered here. An overall analysis of the
sensitivity and frequency response from the calibration files can be found, as
well as documentation on how to record on Linux systems such as a Raspberry Pi.
More importantly, extended calibration files and equalizers can be generated for
each UMIK-1 serial number. This is done with high order interpolation and
extrapolation for most industry standard sample frequencies. The results
increase the calibration range and resolution of your UMIK-1 with
[Audacity](https://audacityteam.org), [SoX](http://sox.sourceforge.net) or your
own custom software.
## Recording
You can record on Linux with the SoX as follows. Install SoX with this command.
sudo apt-get install sox
Query the machine for which audio device are available.
arecord -l|grep ^card
This will return a card number and a device number. Also it will show what the
dip switches settings for the gain in dB
[inside the microphone](https://www.minidsp.com/forum/umik-questions/9249-umik-new-pcb-installation-question).
**** List of CAPTURE Hardware Devices ****
card 1: U0dB [Umik-1 Gain: 0dB], device 0: USB Audio [USB Audio]
Subdevices: 1/1
Subdevice #0: subdevice #0
The factory settings used to be 12dB but is
[currently](https://www.minidsp.com/forum/umik-questions/10285-umik-1-standard-factory-gain)
18dB. Possible values are 0dB, 6dB, 12dB, 18dB, 24dB, 30dB and 36dB. This is
very practical that the settings are show on the command line. That prevents
opening the microphone to see what the gain via the dip switches is set to.
Set the following two environment variables to use the microphone in the
example above.
export AUDIODEV=hw:1,0
export AUDIODRIVER=alsa
Note that here `1` is the card number and `0` is the device number. Use the
values relevant for what the machine offers.
Recording with SoX 60 seconds after 5 seconds of waiting:
rec -q -r 48000 -c 1 -b 24 --buffer 16384 filename.wav trim 5 60
Recording with Audacity works after selecting the 'Microphone - 2.0 root hub'
device for sound input in the sound settings of your window manager. Press 'r'
to start recording and 'space' to stop recording.
## Calibration
In directory `scripts` are scripts to download calibration files, analyze them
and generate improved calibration files supporting a wider range of frequencies.
See directory `download` of downloaded calibration files and directory `stripped`
for the files stripped for further processing.
In the directory `overview` are some overview plots generated on all downloaded
and stripped files. The directory `generated` offers extended calibration files
and graphs in zip files. The calibration files are interpolated and
extrapolated to offer more frequency ranges. The files are self explanatory.
The files also support processing with SoX or Audacity. Some examples are:
[Extended calibration](example/7009115-fit-response.tsv)
Extended calibrations for e.g. SoX for sample frequencies of
[44.1 kHz](example/7009115-fit-sampled-response-44100.xml) and
[48 kHz](example/7009115-fit-sampled-response-48000.xml)
Support for Audacity are a
[filter curve](example/7009115-fit-audacity-filter-curve.txt) and
a [graphical equalizers](example/7009115-fit-audacity-graphical-equalizer.txt).
These files can be imported into Audacity under `Effect / Filter Curve...` and
`Effect / Graphic EQ...`.
Please, create an [issue](https://github.com/PanderMusubi/umik-1/issues) for
serial numbers to support, as generating these files for all available
calibration files does not fit in the available storage here.
## Practical tips
Best is to give each microphone an extra label with its serial number as the
default label with barcode can
[smudge](https://www.minidsp.com/forum/umik-questions/11202-labels-with-serial-numbers-smudge)
and turn unreadable.
Even you do not open the microphone to change its gain via dip switches, the
ring holding the microphone closed can sometimes become loose. Check this
sometimes to prevent damage.
## See also
Product description
https://www.minidsp.com/products/acoustic-measurement/umik-1
Product brief
https://www.minidsp.com/images/documents/Product%20Brief%20-%20Umik.pdf
Product forum
https://www.minidsp.com/forum/umik-questions
Product FAQ
https://minidsp.desk.com/customer/portal/topics/644663-umik-1-related-questions/articles
Home Theater Forum
https://www.hometheatershack.com/forums/spl-meters-mics-calibration-sound-cards/63808-minidsp-umik-1-microphone.html
# Issues
Report following error in `7005770.txt` and its 90 degrees version. The double
minus should be one minus:
19.369 -3.1312
19.611 --3.1221
19.855 -3.1116
The following range misses its minus:
36.403 -1.4134
36.857 -1.3674
37.315 -1.3214
37.78 1.2752
38.25 1.2285
38.726 1.1812
39.209 1.1329
39.697 1.0835
40.191 1.0335
40.691 0.9834
41.198 0.9346
41.711 0.8880
42.23 0.8446
42.756 0.8050
43.288 0.7687
43.827 0.7347
44.372 0.7022
44.925 0.6699
45.484 0.6369
46.05 0.6023
46.623 0.5654
47.204 0.5259
47.791 0.4835
48.386 0.4385
48.989 0.3913
49.599 0.3424
50.216 0.2923
50.841 0.2420
51.474 0.1922
52.115 0.1441
52.764 0.0986
53.42 0.0567
54.085 0.0192
54.759 -0.0128
55.44 -0.0388
56.131 -0.0581
and the following entry misses a minus:
131.807 -0.1416
133.448 0.1403
135.109 -0.1391
This has been manually fixed here in the downloaded file and should be reported
upstream. Also a few more files have similar issues. These should be detected,
fixed and reported upstream too.