Several of the comments posted about my products and my company in this thread are misleading or just incorrect, so I am compelled to respond. I'm not a frequent forum user, so I apologize to all the regulars who might feel like I'm speaking out of line. I mean no disrespect.
For those who don't know me, I built RecordingHacks.com (microphone database), and currently design and voice all the microphones for MicParts.com and Roswell Pro Audio.
Whether you think they're good or bad is irrelevant to my reply. What I was addressing is this characterization of my capsules' response:
That description is inaccurate. See the attached files. One shows frequency sweeps for five randomly selected MXL branded SDC Cardioid capsules. (We have a bag of these, pulled from various MXL mics over the years.) Another attached file shows a direct comparison of one of those to one of the MicParts SDC capsules.
My capsules were designed to be compatible with MXL head amps, which means we use the same diameter and threading -- but my SDC capsules differ significantly from MXL's in design, construction, and sound. If you have a sweep that shows "a peak around 8-10kHz and a dip around 5-6kHz" for my capsule, please send me the graph, with the capsule's serial number. Make sure the capsule has 'micparts' engraved inside, because if not, then you're testing someone else's product.
To repeat what I posted earlier that appears to have been lost in the followups: none of my Cardioid capsules sounds like what Ruud describes, and in the unlikely event that one did, it would fail QC. We test every capsule, and compare each one to the 'gold master' to ensure consistency.
As to the comments that other brands of capsules have a flatter response -- sure, that might be true. We were not trying to build a ruler-flat capsule. Rather, we were trying to build something that sounds good. (Although for those keeping score, the MicParts SDC capsule is within 1dB of flat, out to 9kHz.)
"Often used" by who? If you have specific examples in mind, please share.
My experience is that manufacturers would more likely just skip the testing altogether, and copy a graph from some other mic, or hand-draw something that looks good. Both of those are easier than going to the trouble and expense of testing something.
Further, the contention that 1/3-octave smoothing is inherently inadequate or misleading is, in my opinion, incorrect, about which more below.
Taken in context, your contention ("the graph isn't proof of anything") seems to be that smoothing would make an MXL SDC capsule (big dip at 5k, big hump at 10k) look the same as mine. I swept several of each today on the same rig to disprove the point. The files are attached, see particularly the one that shows one of my capsules and one of MXL's.
The characteristics of the MXL capsule that were so accurately described by RuudNL are easily and obviously visible in these 1/3-octave smoothed graphs. The difference in the graphs is significant. The difference in sound is also significant.
So let's talk more about the apparent evils of smoothing.
I've attached a KM84 sweep, with the 1/3 octave smoothing superimposed on the unsmoothed result. The smoothed line just makes it easier to see the trend. If the capsule's response deviated in a way that you'd hear, the smoothed line would show it. Said another way, I disagree that audible sonic problems are masked by a smoothed curve.
It seems to be worth asking whether any manufacturers pass this standard? That is, does any mic maker publish raw, unsmoothed sweep data for their products? I have not seen any.
I'd bet that most published frequency graphs use *at least* 1/3 octave smoothing. For example, see the Shure or Neumann websites -- two companies that absolutely do great engineering and comprehensive testing, and would be very capable of publishing raw sweep data if they wished. But they don't.
Is that done with intent to deceive? I don't believe so. I believe that those ultra-smoothed graphs are used because they're good enough to communicate the general shape of the mic's response.
I took advantage of my morning in the lab to test several other SDCs that had been mentioned here -- including the MK-012 and 3U CM100. These were all measured on the same rig, within a couple minutes of each other, with precisely matched test conditions. I own only one CM100, and at least two of the other mics listed here. For everything other than the CM100, I swept at least two of them to make sure the response was not anomalous.
The measurement distance is 10 inches, which is why most of these mics have a lift in the bass; that is due to proximity effect. Any speaker or room anomalies are theoretically compensated for by the calibration process.
For those who don't know me, I built RecordingHacks.com (microphone database), and currently design and voice all the microphones for MicParts.com and Roswell Pro Audio.
I never said the capsules are bad,
Whether you think they're good or bad is irrelevant to my reply. What I was addressing is this characterization of my capsules' response:
The MP capsules have a peak around 8-10 KHz and a dip around 5-6 KHz.
That description is inaccurate. See the attached files. One shows frequency sweeps for five randomly selected MXL branded SDC Cardioid capsules. (We have a bag of these, pulled from various MXL mics over the years.) Another attached file shows a direct comparison of one of those to one of the MicParts SDC capsules.
My capsules were designed to be compatible with MXL head amps, which means we use the same diameter and threading -- but my SDC capsules differ significantly from MXL's in design, construction, and sound. If you have a sweep that shows "a peak around 8-10kHz and a dip around 5-6kHz" for my capsule, please send me the graph, with the capsule's serial number. Make sure the capsule has 'micparts' engraved inside, because if not, then you're testing someone else's product.
To repeat what I posted earlier that appears to have been lost in the followups: none of my Cardioid capsules sounds like what Ruud describes, and in the unlikely event that one did, it would fail QC. We test every capsule, and compare each one to the 'gold master' to ensure consistency.
As to the comments that other brands of capsules have a flatter response -- sure, that might be true. We were not trying to build a ruler-flat capsule. Rather, we were trying to build something that sounds good. (Although for those keeping score, the MicParts SDC capsule is within 1dB of flat, out to 9kHz.)
1/3 of an octave can be sufficient, but is often used to cover up the lack in either manufacturing or measuring process.
"Often used" by who? If you have specific examples in mind, please share.
My experience is that manufacturers would more likely just skip the testing altogether, and copy a graph from some other mic, or hand-draw something that looks good. Both of those are easier than going to the trouble and expense of testing something.
Further, the contention that 1/3-octave smoothing is inherently inadequate or misleading is, in my opinion, incorrect, about which more below.
1/3 of an octave can be sufficient, but is often used to cover up the lack in either manufacturing or measuring process. Not saying Matt does this, but the presented graph isn't proof of anything.
Taken in context, your contention ("the graph isn't proof of anything") seems to be that smoothing would make an MXL SDC capsule (big dip at 5k, big hump at 10k) look the same as mine. I swept several of each today on the same rig to disprove the point. The files are attached, see particularly the one that shows one of my capsules and one of MXL's.
The characteristics of the MXL capsule that were so accurately described by RuudNL are easily and obviously visible in these 1/3-octave smoothed graphs. The difference in the graphs is significant. The difference in sound is also significant.
So let's talk more about the apparent evils of smoothing.
I've attached a KM84 sweep, with the 1/3 octave smoothing superimposed on the unsmoothed result. The smoothed line just makes it easier to see the trend. If the capsule's response deviated in a way that you'd hear, the smoothed line would show it. Said another way, I disagree that audible sonic problems are masked by a smoothed curve.
It seems to be worth asking whether any manufacturers pass this standard? That is, does any mic maker publish raw, unsmoothed sweep data for their products? I have not seen any.
I'd bet that most published frequency graphs use *at least* 1/3 octave smoothing. For example, see the Shure or Neumann websites -- two companies that absolutely do great engineering and comprehensive testing, and would be very capable of publishing raw sweep data if they wished. But they don't.
Is that done with intent to deceive? I don't believe so. I believe that those ultra-smoothed graphs are used because they're good enough to communicate the general shape of the mic's response.
I took advantage of my morning in the lab to test several other SDCs that had been mentioned here -- including the MK-012 and 3U CM100. These were all measured on the same rig, within a couple minutes of each other, with precisely matched test conditions. I own only one CM100, and at least two of the other mics listed here. For everything other than the CM100, I swept at least two of them to make sure the response was not anomalous.
The measurement distance is 10 inches, which is why most of these mics have a lift in the bass; that is due to proximity effect. Any speaker or room anomalies are theoretically compensated for by the calibration process.