I have had the same experience with the 158's. With the froglogger the mic
using the Primo EM-158 is powered by a 3volt battery pack. I compared the
binaural 158's (without the 3v battery) with my 183's and was disappointed
that the 158's had a little more self-noise than the 183's. I was using a
Sony Hi-MD recorder. I measured the PIP of the with the 158's plugged at
Subject: 48 VDC. The results are essentially the same as Rob's tests referred
a previous post.
I have been out-of-commission for a while with heart problems and am in need
of a knee replacement. We were in the middle of moving from Colleyville, TX
to Magnolia, TX when my heart started acting up so most of my froglogger and
microphone stuff is in Magnolia but I'm still stuck up here in Colleyville
where my doctors are located. Hopefully I'll be moved by Christmas and will
be where I can run some more tests with the 158's and 183's.
On Behalf Of Rob Danielson
Sent: Sunday, December 09, 2007 10:21 AM
Subject: Re: [Nature Recordists] Experience with BT-BI158's?
At 8:30 PM -0500 12/8/07, Steve Cox wrote:
>Hi Rob, yes I did see that and just about everything else on your
>site! Great information there.
>However, I wasn't sure they were the same mics. These did say Bedford
>Technical Bi-158, not Primo EM-158 so if these really are the same
>mics you could see my confusion. There are more differences than
>I was hoping that they were not the same mics because I wasn't overly
>impressed with the performance on the test. I was hoping for less
>noise, as the description indicates.
They're the same capsules. There's chance the 158's could perform a
tad better with more PIP voltage. The Primo literature states the
EM-158's have 20dBA self noise, which, I agree, should sound less
noisy. In comparison to WL-183's with 22 dB(A) self-noise, one might
hope for a slight improvement. A change of .3 to 1dBA is about the
smallest "step"we can hear. Gerald's test, and others like it, have
told me that all electrets, with the exception of Klas's EMKS-23, are
not ideal for recording ambience in quiet locations.
Electret mics have many, fantastic applications, but I suspect any
nature recordist comparing quiet location performance of a condenser
mic with 17dB(A) or under self-noise to that of inexpensive electret
mics would share your disappointment.
Klas' EMKS-23 are based on Primo EM-23 capsules with an amp he has
crafted. Considering that one would have to invest at least $700 per
capsule for DPA, Schoeps, MBHO and other small-profile comparables,
the EMKS-23 are reasonably priced. Recordists are always looking, but
I do not think there are any low-cost, low-noise, small mics that
will run on PIP.
As the Sony PCM-D50 only has a PIP external mic input and the Fostex
FR2-LE only has 48 volt phantom inputs, perhaps we should dig-up the
simple mods allowing electret mics tp run on 48v. For low-profile,
stereo imaging and other flexibiilities, I'd much rather have
head-wearable EM-158's or WL-183's than X-Y recorded mounted
electrets. Rob D.