Microphone direction

Vladimir_1953

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Preamp, Processor or Receiver
ROTEL RC-990
Main Amp
ROTEL RB-991
Universal / Blu-ray / CD Player
DENON DCD-2000AE, ROTEL RCD-991AE
Front Height Speakers
Dynaudio Crafft
What is the optimal microphone location for measurements in the car?
1. The left side is at the point of the left ear
Right side - at the point of the right ear
2. In the middle of the driver’s seat at ear level
3. ???

Microphone direction?
1. Forward towards the windshield
2. vertically up
 
Presuming you have a Calibration File I would point it either up or down 90 degrees. Probably down to avoid the very close roof reflections.
 
In my truck I point it up and place it at the tip of my nose, left ear, then right ear. I know some of the 12 volt guys move it around a lot, but I have not gotten good results doing that.
 
Microphone Behringer ECM8000
Experimenting 2 mic measurements
 

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Well done Vladmir, a lovely looking Jecklin Disc. IMO this is how all acoustic measurement should be done.
I mean, who listens with their nose?
 
Well done Vladmir, a lovely looking Jecklin Disc. IMO this is how all acoustic measurement should be done.
I mean, who listens with their nose?
Thank you ! Thanks to the disc and separate measurement of right / left, it was possible to minimize early reflections. This had a positive effect on mixing speakers and sound in general. Measurement in front of the nose - an average measurement, which for measurements in the passenger compartment may be sufficient.
But, we are not looking for easy ways ...
 
There is a desire to read and understand why we have TWO ears with an average distance between them of 175 mm, and measurements are made with one microphone installed in front of the nose in the direction of the windshield, although it is known that the directivity of human hearing is 55 degrees for each ear.
 
JBL was able to incorporate a dual mic setup inside headphones that we would wear during the measurements. The instructions were to look straight ahead for the first measurement, then look at the left side mirror and right side mirror for the other two measurements. Worked very well. I wish we could get that same sort of setup, that way your entire body is in with the measurements, which may very well affect the response, although probably not significantly.
 
Well those three JBL measures resulting in six location measurements...... Plus all the HRTF and arithmetic combinations available afterwards. I have seen stringent hall testing using HATS systems and dummy heads. I think the Jecklin is a very practical and available version, it would be great if somebody did a convenient USB version. In a manual Bruel and Kjaer say that the body needs to be kept distant from the mic. 2 Metres or more, thus the tripods we use.
Body close to mic causes anomalies of up to 6dB around 400Hz.
 
JBL was able to incorporate a dual mic setup inside headphones that we would wear during the measurements. The instructions were to look straight ahead for the first measurement, then look at the left side mirror and right side mirror for the other two measurements. Worked very well. I wish we could get that same sort of setup, that way your entire body is in with the measurements, which may very well affect the response, although probably not significantly.
A very interesting solution! Where can I look at measurement graphs and their analysis?
 
Unfortunately they discontinued the MS-8 which was what they used it with. I don't know that there would be any data anywhere.

I think I still have one of those units at my house that I'm not using.
 
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