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Comparison Tests - My own Attempts

Subject: Comparison Tests - My own Attempts
From: "tk7859" tk7859
Date: Thu Dec 21, 2006 3:55 pm ((PST))
As a newcomer to nature recording (somewhat late in life) I'd like to
say how helpful Rob's tests have been in helping me approach this
fascinating subject.

Not wishing to jump in and spend a great deal on equipment whilst
still ignorant I have been experimenting with cheap capsules.  Last
July I made a few posts on my experiments with these including
connecting three Rapid 35-0190 capsules in parallel.

Recently I have made another set of stereo triplets using the Rapid
35-0192 capsule which can be directly mounted on printed circuit
boards thereby eliminating the tricky soldering of leads.  Anxious to
try the new triplets I set up a test to match them against the older
triplets, a single Rapid 35-0190 stereo pair, a Panasonic WM61 stereo
pair and my R=D8DE  NT4.

The test consisted of using each microphone to record 10 minutes of a
ticking clock in my dining room/lounge.  The recorder was a Sony
MZ-RH910 minidisc, recording in linear PCM mode, high mic sensitivity,
manual recording at the "30" level.

I then chose the best 15 seconds from each of the recordings and
subjected them to a spectrum analysis using "Right Mark Audio Analyzer
V5.5"  Studying these analyses it seemed that the "old triplets
(35-0190)  were 2dB more sensitve than the "new triplets (35-0192)",
10dB more sensitive than the single 35-0190 and Panasonic WM6, and a
whopping 17dB more sensitive than the NT4 (and the NT4 cable used did
not have the soldered pads).

m("btinternet.com/AS_Is_CompilationMP3.mp3","//uk.geocities.com/g0sbw");">http:

is a complilation of each of the 15 second recordings (as out of the
recorder with no manipulation) in the following order:- single Rapid,
single Panasonic, Old Rapid 35-0190 triplet, new Rapid 35-0192
triplet, Rode NT4.

Using Audacity, I then amplified the relevant recordings to bring them
up to the level of the "old triplet".  A compilation of the amplified
recordings is here:

m("btinternet.com/adjusted_compilationmp3.mp3","//uk.geocities.com/g0sbw");">http:

The order of apearance, in 15 second tranches, is as given above.

I hope you can manage to download from this site - in the past it has
had problems.

Given my less than youthful hearing (many of my 68 years spent,
without hearing defenders in those days, in underground coal mining
and other high noise environments) it seems that the old triplet is an
easy winner.  The new triplets are disappointing - possibly due to the
camera bag which carries them.   The single Rapid and the Panasonic
are on a par in terms of sensitivity and the jury is still out on the NT4.

Clearly more tests are required, particularly with the "new triplets"
in a more sypathetic housing, and the NT4 powered by the Art Phantom
II I now own in preparation for the arrival of a pair of AT3032s in
the New Year (see, I'm not an old skinflint - maybe scrooge is a
better word given the approaching festive season).

However, the very low cost of the triplets (each capsule about 70 US
cents each) does have a certain attraction.

The "Mic Comparison Tests" photo album at

m("btinternet.com/my_photos","//uk.pg.photos.yahoo.com/ph/g0sbw");">http:

contains photos of the tests.  Click on the album, then on a thumbnail
to get a larger, single picture view and then click on the download
button, top right, to get a screen filling view.

"2nd triple components" show the capsules mounted on their circuit
board, and the mounting board developed to allow their deployment in
the net sides of the camera bag.

"2nd Triple components assembled" shows just that.

"Test Arrangements" shows the clock and the NT4 in position.

"Rapid Single, Panasonic Single" shows their mounting arrangements on
a Jecklin type disc.

"1st Triple" shows the barrier type mounting of this mic.

"2nd Triple" shows the camera bag mounting of this mic.

"NT4"  self explanatory.

There are then 5 diagrams showing the spectrum analyses of each of the
mics as recorded and untouched.

All in all an interesting test session - well worth getting out of bed
a 3am on a December morning.  Such an understanding of the
capabilities of these individual mics could not have been easily
obtained by actual field testing - I just don't have the time even if
I had the weather.  Since October we have had gale after gale with
winds as high as 60mph.  Now we no wind, just freezing fog.

If you have read this far you will have seen there is no original
thought here - just development of good ideas culled from this list -
thanks to All.

However, I do plan to take the triplet idea a little further and use
them in some very lightweight barrier mics which can be easily
transported by foot.

Comments, no matter how critical, are welcome

Cheers

Tom  Robinson







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