While I was at it I decided to compare some of my other mics. Figure 1 shows the comparison of the Earthworks M30 with the newer M3OBX. Figure 2 compares two TEF 05 microphones, both of which have been fitted with new capsules this year. Figure 3 shows the comparison between Brad’s 4007 and mine. Assuming that mine is correct (it compares well with the Earthworks), Brad’s mic did indeed suffer some damage in the fall.

The difference measurement is indeed a valuable tool for answering some of the perplexing questions of audio. pb

The comparison of the two TEF 05 microphones shows that they are a very good match. The frequency and phase responses are nearly identical. Of even more importance, the levels are matched to less than one dB. This makes this pair especially suitable for stereo recording Prior to being damaged, these two mics had a 4 dB difference in sensitivity, requiring recalibration when switching between mics.

Bad news for Brad’s B&K 4007. The comparison between Brad’s and mine should have yielded a nearly straight horizontal line. The deviation from horizontal shows that the mics are not identical. Further comparisons between the two 4007 and the Earthworks M30 showed that Brad’s mic deviates from fiat response.