Posted by: "Rob Danielson"
> walt replied:
>
>
>>>There appears to be no difference in the low end response of the MKH-30
>>>vs the MKH-40.
>
>
> In addition to listening and real time spectral displays like Firium,
> this discussion on the ProSoundWeb was the most in depth I'd read:
> http://tinyurl.com/p5ky2
> I copied this discussion just a while back when researching the
> mkh80. I couldn't get the ProSoundWeb search engine to locate it
> again.
>
> The whole discussion is pretty interesting. There are a couple of
> more references to low Hz response in the entire string.
Note that these references say that Sennheiser adjusts the electronics
of each mic so they match in frequency response. And Sennheiser does say
that in their brochure too. Yes there are differences in diaphragm
response. But those are adjusted before the signal gets out of the mic.
What I said applies on a practical nature recording level, because the
mics are designed and built for matched response. Unless we are going in
and changing the electronics (and I think Rich is the only one trying
that on MKH) we can more or less ignore diaphragm behavior differences,
they were taken care of by the engineers at Sennheiser.
Certainly I've found no reason to boost the MKH-30 low frequency to
match the MKH-40 or MKH-60. Because of differences in overall
sensitivity and to adjust the stereo field I do adjust the relative
signal strength from the Mid and Side differently. This ability to
adjust the relative strengths seems to be missing in the SD 722 decoder.
It's probably a fixed even ratio. Another reason for the full value of
M/S that it should be recorded as M/S and decoded later.
I note in the discussion referenced above that they seem to be
discussing effects at the relatively close distances for mics used in
indoor or music recording. Nature recording uses mics at huge distances
in comparison. So you want to pay more attention to planar source
distribution than point source in their discussion.
I'm also not willing to be near so dismissive of changes in frequency
distribution with distance with my nature recording. Or as impressed
with proximity effect.
To say nothing about all that befalls that sound as it travels in the
natural environment from source to mic. No carefully designed acoustic
space out there.
Their discussion had a little depth, but only in sound recording as they
know it.
In M/S recording one should never expect a match of the mid and side as
they are recording separate soundfields. Forcing the frequency
distribution of the side to that of the mid is a error in my opinion as
the sounds of the two fields could have quite different distance
distributions and sources. You could, somewhat, compare two cardioids
aimed along the figure 8's main axis but the two in opposite directions.
then you would be somewhat closer to comparing recordings of the same
soundfield if you compared that to a figure 8. Even then it would not be
exactly the same. And would just be experimentation, not M/S recording.
I have Firium, but don't like such crude displays for any kind of
analysis. I much prefer full time live sonograms like I have from
SparkXL. Both those and listening I appear to have quite different
interpretations as to cause and effect. I tend to agree with
Sennheiser's published graphs of the two mic's sensitivity with
frequency. Which is very, very close. Just my opinion, for what it's worth.
> Yes, the large capsules and model to model-- all very different. I
> would have retired my NT1A's for 2A's or NT2000's by now except the
> NT1A's are so reliable. I do want to try the NT2000's in worst case
> moisture scenarios because the upper end also seems much smoother.
> Looks like the seal between the electronics and the capsule could be
> less water-tight than the NT1-A tho. You never know until you try.
> Rob D.
I don't expect my NT2000's to become part of my mainline mic collection
so have not worried a lot about moisture sensitivity. I'm certainly not
too worried about liquid water sensitivity as it's easy to protect from
that. It would be humidity levels and temperatures that count most. If
it turns out to be a real problem I could easily mount desiccant in the
setup I'm building.
I'm primarily interested in mic series that contain figure 8's, that's
the big reason I went with MKH mics instead of ME. Within a given series
you have the best chance of having similar mic character. Mixing series
and even more so, mixing manufacturers within a single setup is more
risky in that regard. Figure 8's are the most scarce part of the
equation, thus the focus on them.
Walt
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