At 10:49 AM +0000 3/25/09, Raimund Specht wrote:
>--- In
><naturerecordists%40yahoogroups.com>=
m,
>Rob Danielson <> wrote:
>
>> Thanks for doing a re-test, Curt. There proved to be some good
>> lessons in it so I've uploaded the test as a QuickTime movie:
>>
>>
>><http://www.uwm.edu/~type/audio-art-tech-gallery/pages/Olson_11dB_Mics_Pr=
eTesting-present.html>http://www.uwm.edu/~type/audio-art-tech-gallery/pages=
/Olson_11dB_Mics_PreTesting-present.html
>>
>> or
>> <http://snipurl.com/ehf84>http://snipurl.com/ehf84
>>
>> Scroll down for my analysis. Rob D.
>>
>
>Hi Rob,
>
>Thanks for posting this test.
>
>I think that it should now be accepted that the FR-2LE's and the
>majority of similar recorders such as the TASCAM HD-P2 or Marantz
>PMD661 usually don't require any external preamplifiers and also no
>esoteric upgrades in order to improve their "clarity" or "detail for
>enhanced performance".
>
>Regards,
>Raimund
>
Hi Raimund--
Your input noise measurements have been very instrumental.
As for a carte blanc "policy," I'm inclined to suggest -127 dBu
(A-weighted) as the point where one can begin to expect pre
transparency with the quietest mics. This stems from tests that I and
others have run with Hi-MD's and NT1-A's in which 50% of noise comes
from the recorder input noise. You and others have measured the Hi-MD
recorders at -124 dBu (A-weighted). Using -127 dBu (A-weighted) as a
safe value is also consistent with Table 3 calculations for this and
Curt's gear combinations.
I can see why one would include the PMD-661 in the 'pro-quality" or
"safe bet" group at -125 dBu (A-weighted) assuming one is planning to
use only mics with no less than 10 dB(A) self-noise-- which is very
often the case.
Of course, the color or tonal balance of noise produced by the pre,
especially with recorders in the -121 to 127 dBu (A) range, is likely
to produce some more surprises/perceptual discrepancies with our
working number-principles. I'm always much more content after I hear
a recorder's pre's checked with NT1-A's and the comparison includes
another proven recorder/pre like the SD 722 TASCAM HD-P2, Fostex
FR-2LE and other proven units. We are making slow, but definite
progress in making reliable tests available.
Perhaps most key with these exercises is how they can encourage one
to hear more carefully which allows one to concentrate on
improvements that work and, subsequently, increases our collective
knowledge. I feel that there are still many important discoveries and
improvements to make in far field recording in quiet locations.
Perhaps some radical ones. I also wouldn't want to dissuade people
from experimenting with any gear or technique options as long as they
are willing to elaborate on why they like it!
Thanks again for your help! Rob D.
--
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