Hi Mike--
I got it. Looking forward to listening to your new "chamber." Are
these your test objectives?
(A) Battery box vs PIP? Not sure what an EM158N is,.."N?"
(B) 3/4 vs Full Gain (with mics with > 22dB[A] self-noise)?
(C) 3/4 Trim vs Full Gain using a DIY 3 x Em158N UEC14 M-S combo? By
"Preamp 3-Oclock, Rec Level Max Gain," do you mean, "Trim
3-o'clock...?"
Rob D.
=3D =3D =3D
At 10:23 AM +0000 7/2/09, picnet2 wrote:
>Hi Rob,
>I have recorded with a binaural set based on 2 x EM158's in my
>anechoic chamber - this would be more related to Pauls original
>setup, fairly low noise binaural mics (compared to Panasonic WM6x's)
>I think the point with the recorders is similar to photography, you
>either take the point and shooter and live with the noise - or take
>the SLR and a backpack to match. I know the backpack wont fit in my
>pocket and is far less discrete in use :) Its contents are also far
>more expensive than the recorder in my pocket but alas we know the
>path eventually leads to the NT1A. :)
>
>Regarding the noise, I mailed you on 30th June / EM158 Noise Tests
>with a zip containing an annotated .amad file. I can resend if it
>didnt make it.
>
><http://urlme.net/audio/RecNoise-E158.flac>http://urlme.net/audio/RecNoise=
-E158.flac
>
>The test setup in the Semi finished :/ Semi-Anechoic Chamber:
>
>Pair of binaural EM158 headphones placed pointing up on acoustic
>foam, approx. 0.5M in front of them a very quiet clock.
>
>Recorded Sequence is:
>
>Recorder: Edirol R09HR
>Mic: 2 x Em158N
>Obs: Plug in Power ON - Gain Hi, Max Level (80) =3D Maximum for this recor=
der.
>
>0.5 Sec Gap
>
>Recorder: Edirol R09HR
>Mic: 2 x Em158N
>Obs: Battery box (2 x 6.8 K, 9V battery, 2.2uF decoupling caps -> Out)
>
>1 Sec Gap
>
>Recorder: FR2-LE
>Mic: 2 x Em158N
>Obs: Battery box out -> FR2-LE - Preamp Max Gain, Rec Level Max Gain
>
>Recorder: FR2-LE
>Mic: 2 x Em158N
>Obs: Battery box out -> FR2-LE - Preamp 3-Oclock, Rec Level Max Gain
>
>I then tested a converted Edirol CS-15 Mic:
>
>Recorder: FR2-LE
>Mic: Converted CS-15, Left Channel =3D 3 x Em158N - Right Channel =3D
>UEC14 Figure 8.
>Obs: Battery box out -> FR2-LE - Preamp Max Gain, Rec Level Max Gain
>
>Recorder: Edirol R09HR
>Mic: Converted CS-15, Left Channel =3D 3 x Em158N - Right Channel =3D
>UEC14 Figure 8.
>Obs: PIP Power, Max Level, Gain Hi.
>
>No leveling / matching has been made - the flac contains the
>original cropped audio
>placed into the sequence as described above.
>
>BR,
>Mike.
>
>--- In
><naturerecordists%40yahoogroups.com>=
m,
>Rob Danielson <> wrote:
>>
>> At 7:47 PM +0000 7/1/09, picnet2 wrote:
>> >Hi,
>> >I'll chime in here with my "Holiday Mic test" - not intended to be a
>> >scientific test and wasnt intended for release but I think others
>> >may find it interesting. - Im just debating which (air) mics to take
>> >on holiday.
>>
>> Hi Mike--
>>
>> re:
>>
>> >Avoid the H2 if you can its mic-pre's are hiss factories. (i own
>> >one) - line in is reasonable, LS-10 is a much better choice.
>>
>> If one is going to use low-noise mics? Your test seems to provide an
>> example of the importance of this distinction (see below).
>>
>> >
>> >Heres a quick test where all mics are normalized to roughly the same
>> >level. - This may give some indication of a lower noise mic (NT4 at
>> >around 16 dBA) vs multiple Electrets in a DIY mic costing < 80
>> >dollars. Its noise figure is perhaps around 18-19dBA. The sphere has
>> >~13 dB more output than the NT4 under the same conditions.
>> >
>> ><<http://urlme.net/audio/fr2le-nt4-sphere-r09hr-sphere-nt4.mp3>http://=
urlme.net/audio/fr2le-nt4-sphere-r09hr-sphere-nt4.mp3><http://urlme.net/aud=
io/fr2le-nt4-sphere-r09hr-sphere-nt4.mp3>http://urlme.net/audio/fr2le-nt4-s=
phere-r09hr-sphere-nt4.mp3
>> >
>> >Not a brilliant time to recording in the garden due to the traffic
>> >noise - I wanted to get some impression of how the different rigs
>> >sounded as Ive never tried this combination.
>> >...
>> >Recorded Sequence as follows:-
> > >
>> >FR2-LE with NT4 from its battery.
>> >FR2-LE with DIY Sphere Mic (Polyethylene Marine Buoy + 3xEM158
>> >capsules on each channel) - running via a DIY battery -> XLR box.
>> >plus me moving around to orient the sphere towards the birds.
>> >Edirol R09HR with NT4 from its battery -> Mic / PIP OFF / Gain High
>> >& Max level.
>> >Edirol R09HR with Sphere via the same battery box.
>>
>> If performing to the manufacturer's self-noise spec of 16 dB(A)
>> (which I doubt based on this test ands other comparisons I've made:
>> <http://tinyurl.com/6zhyxx>http://tinyurl.com/6zhyxx) the NT-4
>>_should_ be on the cusp of
>> revealing some input noise difference in the pre performance of the
>> recorders.
>>
>> I took the closest matching segments from your four gear combinations
>> and approximately matched the playback levels:
>> <http://tinyurl.com/kn596f>http://tinyurl.com/kn596f
>>
>> This "hiss" is fairly well matched in segments 1,2 and 3 suggesting
>> that these three mics/powering conditions have similar noise
>> performance that is audible above the recorders' pre noise,...
>> HOWEVER, what happened to the "hiss" in section #4?
>>
>> This discrepancy suggests to me the "hiss" in tests 1, 2 and 3 is
>> environmental and not mic-self noise audible above the pres. (Or
>> another, yet accounted for change in the results Test 4).
>>
>> You'll probably need to do such comparisons in a much quieter/more
>> controlled location and, better yet, use/include your NT-1A's for
>> reference. Probably best that all of the combos be recorded at max
>> or close to max gain too. Rob D.
>>
>>
>> >BR,
>> >Mike.
>> >
>> >--- In
>> ><naturerecordists%40yahoogroups.com><naturerecordists%40=
yahoogroups.com>
>> >Rob Danielson <type@> wrote:
>> >>
>> >> At 5:36 PM +0000 7/1/09, Tom wrote:
>> >> > > If one is only going to use noisy mics (as Klas points out), the=
n one
>> >> >> can save money and buy an Zoom H2. An LS-10 provides no real
>> >> >> advantage and still has more input noise than most recordists lik=
e
>> >> >> when they discover the important role mic-self noise can play. :-=
)
>> >> >
>> >> >Having had personal experience of both these recorders I'd have to
>> >> >say that the LS-10 does have significant advantages over the H2. If
>> >> >you keep the "Mic Gain" switch in the low range the input noise is
>> >> >low enough that it doesn't impinge on recordings made with a K6/ME6=
6
>> >> >with a reasonable degree of ambient sound (wind, birdsong, insects
>> >> >etc.)
>> >> >
>> >> >The H2 on the other hand had a pretty awful mic input which was
>> >> >significantly noisier than using the built in mics. The only way
>> >> >you'd want to use the H2 would be with an external mic preamp which
>> >> >would negate the cost saving over the LS-10!
>> >> >
>> >> >These are just subjective observations, and I can't directly compar=
e
>> >> >the two as I sold the H2 in order to trade up to the LS-10 - if
>> >> >anyone has the means to directly compare the mic inputs on the two
>> > > >units I'd be interested to see the results.
>> >> >
>> >> >Tom W.
>> >> ><<<http://www.pterodaktyl.co.uk/>http://www.pterodaktyl.co.uk/><htt=
p://www.pterodaktyl.co.uk/>http://www.pterodaktyl.co.uk/><<http://www.ptero=
daktyl.co.uk/>http://www.pterodaktyl.co.uk/><http://www.pterodaktyl.co.uk/>=
http://www.pterodaktyl.co.uk/
>> >> >
>> >>
>> >> Hi Tom--
>> >> Listening for "quality" is inherently "subjective," so such
>> >> observations are equally, if not ultimately, more important. A
>> >> technical note to support your observation: An ME-66 mic with
>> >> ~10dB(A) self-noise _should_ show-up the pre differences in the H2
>> >> and the LS-10. However, if one plans to use electret mics of the typ=
e
>> >> that Paul asked about (with more than 22dB[A] self-noise) any pre
>> >> difference would not be audible. This might be an important fact if
>> >> one knows that one will only use the electret or other noisier mics
>> > > with the recorder. Rob D.
>> >>
>>
>>
>> --
>>
>>
>>
>
>
>
--
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