This thread serves to gauge interest in a calibration of measurement microphones by the substitution method.
The idea is that we buy/borrow/steal a calibrated microphone and use the substitution method to measure the relative responses.
This would probably involve me making up a measurement jig to accurately replace microphones in front of a test woofer and tweeter and take measurements of the various microphones and subtract them from a known reference.
All said and done we would likely end up with a measurement uncertainty on the order of 0.5 dB 100Hz up to 5khz, rising to 1dB up to 10kHz with uncertainty rising above. The LF calibration would depend on the method employed, but would result in a calibration accurate enough for sensible loudspeaker modeling.
Due to the cost of purchasing a calibrated mic (likely a calibrated Monacor MCE-40 or Behringer ECM-8000) I would have to charge a fee to recoup the costs of making a jig allowing repeatable measurements as well as the calibrated mic.
Gerhard, Gert and I are definitely doing the calibration, but I'd like to gauge who'd like to have a mic calibrated and whether a cost of ~R350 would be in order. If there is sufficient interest I may purchase a better microphone.
I am tempted by a model from Earthworks (a very good electret mic) or even something externally polarized.
The idea is that we buy/borrow/steal a calibrated microphone and use the substitution method to measure the relative responses.
This would probably involve me making up a measurement jig to accurately replace microphones in front of a test woofer and tweeter and take measurements of the various microphones and subtract them from a known reference.
All said and done we would likely end up with a measurement uncertainty on the order of 0.5 dB 100Hz up to 5khz, rising to 1dB up to 10kHz with uncertainty rising above. The LF calibration would depend on the method employed, but would result in a calibration accurate enough for sensible loudspeaker modeling.
Due to the cost of purchasing a calibrated mic (likely a calibrated Monacor MCE-40 or Behringer ECM-8000) I would have to charge a fee to recoup the costs of making a jig allowing repeatable measurements as well as the calibrated mic.
Gerhard, Gert and I are definitely doing the calibration, but I'd like to gauge who'd like to have a mic calibrated and whether a cost of ~R350 would be in order. If there is sufficient interest I may purchase a better microphone.
I am tempted by a model from Earthworks (a very good electret mic) or even something externally polarized.
