wireman wrote:Does anyone know what the cheapest calibrated mic is? I was thinking of getting the UMIK-1 next time I'm in the USA. Don't really have a serious application but I'm interested in the frequency response of a few locations.
Pretty certain it's the Dayton Audio EMM-6 for best price calibrated microphone, for your purpose.
I have been using the Dayton Audio EMM-6 which comes with a unique serial number (you must be careful cos this serial number is easily erased by rubbing or solvents such as hand cream) so advise that you copy the serial number and store in a safe place, that you can use to download the associated calibration file, from their website.
Bought in 2016 from Soundimports.nl which is now soundimports.eu (based in the Netherlands).https://www.soundimports.eu/en/test-measurement/
Pretty certain there are now some places in the UK IIRC where you may purchase one, please google.
Here you gohttps://wallofsound.co.uk/p-category/test-equipment/
One challenge is learning how to use these calibration files in your software, I use REW(Room Equalisation Wizard) for measurement. Some editing of the file is needed for the calibration file provided by Dayton Audio.
The EMM-6 ideally requires that you obtain a secondary device, an SPL meter, if you wish to be precise about the levels at which measurement is done, in REW. EMM-6 is an electret capacitor(condenser) microphone and needs phantom power from your audio interface. An SPL Meter is nevertheless a good thing to have if you are "serious" about your audio. google(search) SoundonSound for Hugh's recommendations on SPL meters.
I understand that the USB versions of Dayton Audio measurement microphones (which I have no experience with) work with REW in a slightly different way, and in addition to calibration, they have some way of interacting with the software, to omit this need for an SPL meter. It's all explained on the REW site.
Just to be clear, depending on your measurement position - and distance from the speakers, these tools (REW and the measurement microphone) provide a decent enough view of your speakers frequency response (as measured), and interesting waterfall plots of the decay of each frequency. And some of this can be done in real time IIRC, so you can adjust things on your speaker or room acoustic treatment and see the impact (you should wear some earplugs while doing this in real time, to remain sane and not damage your hearing).
While all manner of arguments can be made for the effectiveness or otherwise of these cheaper/free solutions, and the impact of the non-anechoic environment in which the measurements are obtained, if you take a few measurements from slightly different positions in your room, hopefully not too far from each other, you get a really good sense of how one speaker compares with another speaker, or how tone control adjustments on an active speaker affect frequency... definitely an education, makes you more appreciative of what's going on, at a basic level, in the frequency and time domain.
Unfortunately it opens a can of worms - a whole universe of information/curiosity that takes you down lots of rabbit holes, settings, time windows, phase, etc, and an effort to make sense of it all. Depends on what you want to achieve.