Microphone calibration file

I did a search here on the forum about microphone calibration files and I was wondering if the method of intervening on the file based on microphone models with higher specifications and costs, can be useful to obtain/improve the measurement quality of the microphone.

mic. ECM8000
 
Yes it can. These are fairly flat up to 1-2kHz and not bad up to 5kHz so if this covers your crossover ranges then you should be right to voice them in.

I might have a calibration file, I know a few here do. There's a little variability but as I was saying, within voicing range.
 
with calibration files and without. I'm perplexed, I don't see big differences and... there must be something I'm doing wrong. this measurement is done with the LS 3/5a hybrid finished in the last few days.

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I looked at the calibration file you can download from the site a few months ago, and it looks quite a bit like the one I made from a calibrated mic for my ECM8000 many years ago (2008?) even though their design and mic source has likely changed since then.

These things can vary from sample to sample by a dB or two in sensitivity and response, but a measurement is better than no measurement and these are often pretty close, in my limited experience. I have only messed around with three of them. Two old ones which were almost identical and one new one.

I recently had a design of mine measured by a Klippel unit, and the high frequencies looked pretty close, so I think that part of my cal is alright, anyway...
 
if I understand correctly, you are telling me that I should raise the measurement level - when I do the Level check, if I remember correctly, I go around -22-23db, I raise it up to -12 and tighten the scale from 20hz to 25Khz?

later I do other measurement tests, I try to measure also the other type of crossover (the one with the different approach) this time I place the microphone on the Nikon tripod (if I find one) and maybe I put it about 1 meter away and well aligned to the speaker.
 
In REW looking at the graph - hit the box named "Limits" upper right.

Add 10 in "SPL Top" and -40 in "SPL Bottom". Hit Enter.

Now you will see your measurement like most presentations on this site. I hope it's clear that now you see much deeper into the measurement but all levels are the same. Same measurement, different presentation scales.

As of now, you have such an tremdeous large range for dB that small variations can't be seen.

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Yes - but you are still 50dB to "large". That measurement should use 10to60 dB top/bot of the scale. You probably also want to "smooth" (average) the trace - this is made in the Actions button, also up right. Do e.g. 1/12 smooting.

Now you can compare with what most other show here.

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You can get something from a cardioid, but it isn't going to tell you much because they are not generally "flat" mics. They typically have presence peaks and such. Cardioids also have proximity effect and can't be trusted below a few hundred Hz at least.

Go to your impulse tab and make the gate drop about 5ms after the start of the impulse. That will remove room reflections and give you a better idea of actual treble response (if you had a flat mic, that is)
 
Well, now I understand why a guy in a video started the measurement and ran away like flash and when the measurement was finished he returned to the station. 😀

I don't understand what you mean with - Go to your impulse tab and make the gate drop about 5ms after the start of the impulse.
 
the image above is actually the measurement of the hybrids with the yellow cone. 🙂
this type cross,