Hi Paul--
Here are some test materials in a folder to download. I recorded both
mics with 58.6 dB of Gain with a SD 744T recorder.
http://tinyurl.com/y8haout
The Hz response on the two mics is very different. Mic self-noise,
high in register with both mics, is not significantly different in
color.
Using RMS matching of pink noise is the only way I know of to match
playback levels when the tonality of the two mics differs as
significantly as these do. With the additional LF response it has,
the less sensitive NT2-A needed only .5dB of additional gain to match
the NT1-A (pink noise RMS). You can easily hear the additional LF
response in the room tone/tick section as well and there's not much
LF there to work with!
I we assume as Rane Table 3 suggests that the mic pre in the 744T
[measured at -130dBu (A weighted)] is quiet enough for an NT1-A mic
(which we also know from other tests), then I don't understand why
Rane Table suggests a quieter pre is needed to become transparent
behind the NT2-A. When the signal output of the two mics is matched,
the sonograms I've made indicate that the NT2-A has slightly more
effective self-noise noise, not less. In my experience, this usually
means the pre can be slightly noisier, not less. If I've missed
something glaring, I'm ready fer educatin' Rob D.
>
>At 5:03 AM +1100 4/1/10, Paul Jacobson wrote:
>>
>
> >On 31/03/2010, at 5:19 PM, Rob Danielson wrote:
>>>
>>> Rode NT-1A 25 5 -118.83 -128.8 dBu YES, A-weighted
> >> Rode NT-2A 16 7 -120.70 -130.7 dBu?? Side by
>>> side, the 2A is noisier than the 1A. In practice one could get by
>>> with a slightly "noisier" pre, not a "quieter" one and one would not
>>> need -130.7 dBu (A weighted).
>>
>>There is no question that the NT-2A has a higher level of
>>self-noise, but based on the published specs if you recorded both
>>the NT-1A and NT-2A at identical gain settings on the same recorder
>>the recorded mic noise floor of the NT-2A _should_ be lower in terms
>>of of dbFS than the recorded noise floor of the NT-1A. I'd be
>>interested to see your results of such an unadjusted comparison.
>
>Hi Paul--
>
>Its on the test "to-do" list. I'm not following how rec gain makes a
>difference in mic self-noise performance and the resulting recording
>if a sufficiently quiet pre is used. Such a pre would be necessary to
>compare the self-noise performance of the two mics.
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