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Using microphone to measure Db(A) and Db(C) ?

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Skybuck Flying

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Aug 29, 2009, 10:40:43 PM8/29/09
to
Hello,

I have two microphones:

1. A Fica CMP-202 computer microphone.

(I got it for free a long time ago from somebody.)

2. A Pyramid/Pole like microphone DM-A409 that came with my 7.1 Receiver
(Denon AVR 1909).

(Bought this recently... seems quite an impressive microphone according to
some charts it was able to capture ?)

Anyway I was wondering if these microphones are suited to do certain sound
measurements in either Db(A) or Db(C). (Maybe use GoldWave for analyses ?)

I want to measure the sound level that is coming from the cars/trucks/busses
outside.
(I want to measure the sound level outside and inside my living room).

Would these microphones be suited for the task do you think ?

I was also considering buying a special microphone like this one:

http://www1.conrad.nl/scripts/wgate/zcop_nl3/~flN0YXRlPTE5MDM3OTk1OTk=?direkt_aufriss_area=SHOP_B2C_Metering&~template=PCAT_AREA_S_browse&p_page_to_display=&catalogs_sub_id=sub12&aktiv=12&navi=oben_1

Product is called: "SL-400 decibelmeter " (in dutch)

Suppose the answer would be: "No your current microphones are not suited for
the task..."

then I wonder what would be the difference between these microphones and a
specialized microphone ?

Can anybody explain ?

Bye,
Skybuck.


Skybuck Flying

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Aug 29, 2009, 10:48:01 PM8/29/09
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Also...

I have another question:

Why is DB measured in negative/minus ?

Example:

-40 Db

(I see many examples of this for example the receiver volume level... and
goldwave bar chart in volume/play control)

Bye,
Skybuck.


Skybuck Flying

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Aug 29, 2009, 10:56:13 PM8/29/09
to

"Skybuck Flying" <Blood...@hotmail.com> wrote in message
news:cbe57$4a99e85d$d53372a9$29...@cache2.tilbu1.nb.home.nl...

I am gonna gather some links here for further reading:

http://www.phys.unsw.edu.au/jw/dB.html

This link has one line about negative db... and some more... but it's a bit
too technical for me at the moment ;)

"
It is also possible to have negative sound levels: - 20 dB would mean a
sound with pressure 10 times smaller than the reference pressure, ie 2 �Pa.
"

Another link giving a technical description... so far it seems to be
something technical, and it seems to be about "relative"... and it also
seems quite important ! If it's not understood it could be meaningless ?!

http://www.answerbag.com/q_view/11521


"
A manufacturer may choose any method to describe their equipment. Unless you
know what reference is being used, the results are somewhat meaningless.
"

There is also a secondary answer which is kinda interesting... it mentions
the "dBFS" scale/measuring system.. specially for digital equipment... hmmm
;)

And it gives a little 16 bit example...

Bye,
Skybuck.


Skybuck Flying

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Aug 29, 2009, 11:02:08 PM8/29/09
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Hmmm... this link starts out with writing the following:

http://arts.ucsc.edu/EMS/music/tech_background/TE-06/teces_06.html

"
The decibel (abbreviated dB) must be the most misunderstood measurement
since the cubit. Although the term decibel always means the same thing,
decibels may be calculated in several ways, and there are many confusing
explanations of what they are.
"

It then goes on about great differences in measurements like 10 vs
1.000.000.000.000.

It then goes on to explain some db system where logarithms are used for
"convenience".

This is a great thinking-error by whoever invented it.

Human beings are famous for not understanding logarithms... so it doesn't
really make it any more convenient... on the contrary it makes it much
harder to understand.

Don't take my word for it... Watch this professor in action =D:

http://www.youtube.com/watch?v=F-QA2rkpBSY

Bye,
Skybuck.


Skybuck Flying

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Aug 29, 2009, 11:27:06 PM8/29/09
to
Never the less... this is case where a logarithm might make it easier for
human beings to compare sound levels... since the ear seems to work
logarithmetic-like as well... hihi.

But still it makes it a bit harder to compare all kinds of devices... "do
they have a reference point or not ?" ;) "And what kind of systems are they
using ?" ;)

Anyway wikipedia also has two interesting articles.

http://en.wikipedia.org/wiki/Decibel

One specifially about DB(A) which is used by law system here in Netherlands
;)
(Most interesting parts are the critique on this system... and it also has a
picture of a measuring device ;))

http://en.wikipedia.org/wiki/A-weighting

Still gotta read it... but now I must do something else... but will probably
read this when I come back or at least have a good glance over it ! ;) :)

Bye,
Skybuck.


Skybuck Flying

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Aug 30, 2009, 12:02:15 AM8/30/09
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And indeed, wikipedia also mentions DB(A) bad-suited for what it's used for:

http://en.wikipedia.org/wiki/A-weighting

"
The curves were originally defined for use at different average sound
levels, but A-weighting, though originally intended only for the measurement
of low-level sounds (around 40 phon), is now commonly used for the
measurement of environmental noise and industrial noise, as well as when
assessing potential hearing damage and other noise health effects at all
sound levels; indeed,

!!!
the use of A-frequency-weighting is now mandated for all these measurements,
although it is badly suited for these purposes, being only applicable to low
levels so that it tends to devalue the effects of low frequency noise in
particular[1].
!!!

"

Bye,
Skybuck.


Skybuck Flying

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Aug 30, 2009, 12:15:14 AM8/30/09
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Ok,

I am trying to find more information about the DM-A409 microphone that came
with the Denon AVR 1909.

Quite funny really, I came across this website which has one little line of
important information about it:

"Accurate microphone DM-A409 (included) custom made by Audio-Technica"

http://www.audio-net.com.ar/denonavr1909.htm

So now I go check out audio technica website at:

http://www.audio-technica.com/world_map/

Maybe it has more information about this microphone ;) :)

Or maybe it has comparable microphones or other interesting information ! ;)

Bye,
Skybuck.


Skybuck Flying

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Aug 30, 2009, 12:23:36 AM8/30/09
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Well the "custom made" probably says it all...

This microphone is not really for sale at their website anyway.

I did see a couple of them on e-bay and such.

Audio-technica does have a lot of microphones... but none in this shape...

I would guess these come closest to it:

http://www.audio-technica.com/cgi-bin/product_search/wired_mics/mics_by_type.pl?product_type=Microphones%3A+Lavalier

I think it's time to give this microphone a test myself and connect it to my
soundblaster and see what happens ;) :)

Bye,
Skybuck.

"Skybuck Flying" <Blood...@hotmail.com> wrote in message

news:875c4$4a99fcce$d53372a9$28...@cache3.tilbu1.nb.home.nl...

Skybuck Flying

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Aug 30, 2009, 12:38:00 AM8/30/09
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Hmm this microphone seems to be very good at picking up sounds... there is a
catch however...

The volume is very low... so to be able to hear it it must be amplified.

Fortunately goldwave (wave) editor has a effect/volume/change volume
option/tool that allows the volume to be enhanced by 20 points whatever that
means... and then this can be repeated one more time...

After applying the change volume effect twice it sounds pretty good ! (Even
picking up low sounds it does pretty well).

I am already convinced this is a good microphone however now I am getting
slightly worried that the car sounds from outside might actually damage
it... but then again... the testing sounds from the receiver where also
pretty loud so it can probably handle it ! :)

I wonder how much this microphone is worth LOL :) For example how much would
a comparable microphone cost ?!?

Anyway I am hoping now that I can use this microphone to try and do some
meaningfull measurements ?!

I am not scared to do some arithmetic/math to convert whatever it takes to
DB(A) or DB(C)... I might actually learn something from doing the math or
so... and get a better understanding of it... and then maybe I will also be
more sure that it's more or less correct for my purposes and law or so ;) :)

I do have a little problem with guessing the distance to the street/cars. I
am on 5th floor or so... so I am up in the air... I don't know if that
matters much... it probably does matter a little bit... but the sounds are
also reflected by the surrounding buildings...

Bye,
Skybuck.


Skybuck Flying

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Aug 30, 2009, 1:09:40 AM8/30/09
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"Frank Buss" <f...@frank-buss.de> wrote in message
news:h311pp23j31j$.1h6nk3g8dlp2r.dlg@40tude.net...

> Skybuck Flying wrote:
>
>> I wonder how much this microphone is worth LOL :) For example how much
>> would
>> a comparable microphone cost ?!?
>>
>> Anyway I am hoping now that I can use this microphone to try and do some
>> meaningfull measurements ?!
>
> No, use a calibrated measure microphone.

I already have a microphone. Now it "just" needs to be calibrated lol :)

But this raises interesting questions:

How am I suppose to understand the law if I don't know what kind of decibels
me, my systems, or other people's cars/trucks/busses are producing ?

There must be a way for me to calibrate my microphone... ?!?

So the question now becomes how to calibrate my microphone so it can be used
to interpret the law and such...

(I could simply follow your advice and buy a "calibrated" microphone but
then how would I know if it was calibrated properly in according with law ?!
;) :) <gje lol> I must be able to prove/test it somehow ? ;))

>> I am not scared to do some arithmetic/math to convert whatever it takes
>> to
>> DB(A) or DB(C)... I might actually learn something from doing the math or
>> so... and get a better understanding of it... and then maybe I will also
>> be
>> more sure that it's more or less correct for my purposes and law or so ;)
>> :)
>

> You may need some years to learn the basics, e.g. how to develop a FIR
> filter with many taps for the filter function.

The filter can be applied later... these are weights if I understand
correctly.

So first I would need a system without the weights... is this the SPL you
mentioned ?

Bye,
Skybuck.


Skybuck Flying

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Aug 30, 2009, 1:17:33 AM8/30/09
to
Ok,

I found some interesting information in the dutch law... maybe I can make
some sense of it...

I'll post it here in dutch... you'll have to use google translate to
translate it into your language.

However some symbols and formula's are lost in plain text so here is the
link in case you are interested in learning more about how the dutch law
deals with sounds/decibels and measurements ;) :)

http://wetten.overheid.nl/BWBR0003529/geldigheidsdatum_30-08-2009


"
Bijlage I
Voorschrift m.b.t. het berekenen en meten van de geluidwering
1. Algemeen
1.1De bepaling van de geluidwering dient te geschieden voor de octaaf-banden
met de middenfrequenties 125 Hz, 250 Hz, 500 Hz, 1000 Hz en 2000 Hz.
1.2Bij de bepaling van de geluidwering van de gevel dient te worden
uitgegaan van het A-gewogen referentiespectrum, behorend bij het equivalent
geluidsniveau buiten de woning of het andere geluidsgevoelige gebouw.
Het A-gewogen referentiespectrum wordt zodanig weergegeven, dat het
bijbehorend geluidsniveau 0 dB is.
1.3Tenzij anders vermeld en gemotiveerd, wordt bij de bepaling van de
geluidwering als referentiespectrum voor weg- of spoorweglawaai het in tabel
1 gegeven standaardspectrum gehanteerd.
Tabel 1. Het A-gewogen standaardspectrum in octaafbanden voor weg- of
spoorwegverkeer
Octaafbanden met middenfrequentie in Hz
frequentie (Hz)12525050010002000
Index i12345
Ci (dB)�14�10�6�5�7

1.3.aAls in de maatgevende periode op de betreffende spoorweg geen
railvoertuigen passeren behorende tot de categorie�n 4 of 5, bedoeld in
artikel 1 van het Reken- en meetvoorschrift railverkeerslawaai, kan de met
behulp van het standaardspectrum bepaalde geluidwering met 3 dB(A) worden
vermeerderd.
1.4De geluidwering van de gevel wordt genormeerd voor de nagalmtijd in de
geluidsgevoelige ruimte. Voor geluidsgevoelige ruimten in woningen bedraagt
de referentienagalmtijd To 0,5 seconde voor de onder 1.1. genoemde
octaafbanden. Voor geluidsgevoelige ruimten, anders dan woonruimten, in
andere geluidsgevoelige gebouwen dan woningen bedraagt de
referentienagalmtijd To 0,8 seconde voor de onder 1.1. genoemde
octaafbanden.
1.5Indien door een aanwezige gevel, anders dan door het openen van ramen,
ventilatie kan plaatsvinden, zoals door kieren, ventilatieroosters of
ventilatieklepjes, dan wordt de geluidwering bepaald voor de situatie dat
desbetreffende ventilatieopeningen zijn gesloten en afgedicht. Ter
compensatie wordt een opening in de gevel in rekening gebracht ter grootte
van de helft van de volgens de bouwverordening te bepalen ventilatie-opening
in de gevel, met een geluidsisolatiewaarde van 0 dB(A) voor het netto
oppervlak van de opening.
Indien evenwel ventilatie-openingen in de gevel aanwezig zijn of worden
aangebracht waaraan een hogere geluidsisolatiewaarde wordt toegekend dan 0
dB(A), dan worden deze bij de bepaling van de geluidwering geopend
respectievelijk geopend geacht.
2. Meetmethode
2.1Ter bepaling van de waarde van de geluidwering van de gevel worden
metingen uitgevoerd per begrenzingsvlak met behulp van een luidspreker of
een luidsprekerscombinatie op zodanige wijze dat de metingen voor wat
betreft de invalsrichtingen representatief kunnen worden geacht.
Daarbij wordt uitgegaan van een geluidsbron op ��n of meer vaste posities.
Het begrenzingsvlak wordt daartoe onder een hoek van 45� � 5� ten opzichte
van de normaal aangestraald, zodanig dat de geluidsbelasting op de andere
van belang zijnde begrenzingsvlakken te verwaarlozen is. De afstand van de
bron tot het begrenzingsvlak gemeten vanuit de geluidsgevoelige ruimte is
ten minste tweemaal de gevelbreedte (van die ruimte). De bron dient een
signaal voort te brengen met het karakter van een ruis en met een breedte
van tenminste ��n octaaf waarvan de middenfrequentie overeenkomt met de
middenfrequentie van het te meten octaafgeluiddrukniveau. De
frequentiekarakteristiek moet vlak zijn binnen een hoek van ca. 40�.
De door de bron op de meetplaatsen veroorzaakte geluidsniveaus dienen ten
minste 10 dB hoger te zijn dan het achtergrondgeluid, dat wil zeggen alle
geluiden die niet van de bron afkomstig zijn.
2.2Het geluiddrukniveau buiten het gebouw L2, i wordt per octaafband bepaald
op 2 meter afstand van het begrenzingsvlak. Het (ruimtelijk gemiddelde)
geluiddrukniveau binnen de ruimte Lb, i wordt per octaafband bepaald. Voor
indicatieve doeleinden kan voor de bepaling van het geluiddrukniveau binnen
de geluidgevoelige ruimte � Lb, i � eventueel worden volstaan met ��n meting
op 1 � 1,5 meter van het gevelvlak, ter hoogte van het middel van de gevel.
Ter compensatie van een systematische fout dient het aldus gemeten
geluiddrukniveau met 1 dB te worden verlaagd.
2.3In de geluidsgevoelige ruimte dient per octaafband met de
middenfrequenties 125 Hz, 250 Hz, 500 Hz, 1000 Hz, 2000 Hz, de nagalmtijd Ti
te worden bepaald. Uit de waarden L2, i, L b, i en Ti en de
referentienagalmtijd To, (zie onder 1.4) wordt het parti�le
geluidsniveauverschil van de gevel Di bepaald volgens de formule:
Di= L2, i � Lb, i + 10 log (Ti/To) (dB) (1)
2.4In verband met reflecties van het geluid op de gevel dient het parti�le
geluidsniveauverschil gecorrigeerd te worden voor de bepaling van de
parti�le geluidwering volgens de formule:
Gi = Di�Ci (dB) (2)
waarin Ci = o of 3 dB.
Uit de partiele geluidwering Gi (voor de octaafbanden met de
middenfrequenties 125 Hz, 250 Hz, 500 Hz, 1000 Hz, en 2000 Hz) wordt
rekening houdende met het standaardspectrum de waarde van de geluidwering
van de gevel bepaald volgens de formule (5) (zie onder 3.5.).
2.5De bij de bepaling van de geluiddrukniveaus te gebruiken apparatuur dient
zodanig te zijn dat de meetketen voldoet aan IEC-publicatie 651, uitgave
1979, type 2.
3. Berekeningsmethode
3.1De partiele geluidwering (Gi) van een gevel � dat wil zeggen de
geluidwering in ��n octaafband (i) � wordt berekend uit de geluidsisolaties
van de totale, uit te onderscheiden elementen samengestelde, gevel met de
formule:

waarin:
Ri=de luchtgeluidsisolatiewaarde van de gevel in de octaafband i in dB.
Cr=correctieterm in verband met de gevelreflectie.
V =het volume van de geluidsgevoelige ruimte.
To=de referentienagalmtijd: 0,5 s, tenzij anders is aangegeven.
S =totale geveloppervlakte in m� (gezien vanuit de geluidgevoelige ruimte).

3.23.2. In formule (1) geldt:

waarin:
n =het aantal te onderscheiden elementen waaruit de gevel is opgebouwd.
Sj =het oppervlak van het gevelelement j in m�.
Rji=de (laboratorium) luchtgeluidisolatiewaarde van het gevelelement j in de
octaafband i in dB.
K =kierterm. Indien speciale dubbele kierdichting worden toegepast, kan K op
10�5 worden gesteld, in de overige gevallen op 3.10�4.
Indien een afwijkende kierterm wordt toegepast, wordt deze afwijking nader
gemotiveerd.

3.3De correctieterm Cr (gevelreflectie) bedraagt 3 dB indien de hoek tussen
de kortste verbindingslijn geluidbron � gebouw en de normaal op de gevel of
het gevelvlak 70� of minder is en bedraagt 0 dB indien deze hoek meer dan
70� is. Bij de bepaling van de parti�le geluidwering van een gevel volgens
formule (3) wordt gerekend met de gebruikelijke gevelstructuren. Indien er
sprake is van een bijzondere gevelstructuur kan een correctie worden
toegepast welke wordt gemotiveerd.
3.4Indien de waarden Rj gegeven zijn voor het A-gewogen
standaardreferentiespectrum � dus in dB(A) �, geven de formules (3) en (4)
direct de geluidwering van de gevel in dB(A).
3.5Uit de parti�le geluidwering van de gevel (Gi) wordt de geluidwering van
de gevel berekend met de formule:

waarin:
Ci = standaard-referentiespectrum in dB (zie onder 1.2 en 1.3.).
"

Bye,
Skybuck.


Skybuck Flying

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Aug 30, 2009, 1:20:35 AM8/30/09
to
Oops... I just noticed this is for inside buildings... that could be
interesting as well...

But first I want to know formula's/calibration for outside buildings...

So me go search some more ! ;)

Bye,
Skybuck.

"Skybuck Flying" <Blood...@hotmail.com> wrote in message

news:19d51$4a9a0b6a$d53372a9$13...@cache3.tilbu1.nb.home.nl...


> Ok,
>
> I found some interesting information in the dutch law... maybe I can make
> some sense of it...
>
> I'll post it here in dutch... you'll have to use google translate to
> translate it into your language.
>
> However some symbols and formula's are lost in plain text so here is the
> link in case you are interested in learning more about how the dutch law
> deals with sounds/decibels and measurements ;) :)
>
> http://wetten.overheid.nl/BWBR0003529/geldigheidsdatum_30-08-2009
>
>
> "
> Bijlage I
> Voorschrift m.b.t. het berekenen en meten van de geluidwering

<snip>


Skybuck Flying

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Aug 30, 2009, 1:25:16 AM8/30/09
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Ok,

I am now one step further :) I like taking it a step at a time lol.

This is the dutch law called "soundobstruction" in english ;) or something
like that ;) :)

(In dutch: "wet geluidhinder" wet = law. geluid = sound. hinder =
obstruction.)

(Wgh in short)

http://wetten.overheid.nl/BWBR0003227/geldigheidsdatum_30-08-2009

(Again use google translate if you want to understand some if it if you
can't understand dutch :):):))

Bye,
Skybuck.


Skybuck Flying

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Aug 30, 2009, 1:41:56 AM8/30/09
to
The dutch law mentions international "huppledepup" lol.

dB(a) as determined by "Internationale Electrotechnische Commissie".

Searching google takes me to this website in dutch which says Netherlands is
pretty much at the forefront of "sound laws" ;)

http://s1006.nxs.nl/ski/afdrukken.asp?ID=WGHBI.1

And via this website I come at this document which explains how to do a
measurement...

It's again in dutch though but could be interesting:

http://www.vrom.nl/docs/milieu/handleiding_meten_en_rekenen_industrielawaai_module_b.pdf

Bye,
Skybuck.


Skybuck Flying

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Aug 30, 2009, 2:00:46 AM8/30/09
to
Some more interesting links:

(Less interesting, too many links, too much information, too many subjects,
but it did have a further link to the link at the bottom):

http://www.vrom.nl/pagina.html?id=10054

According to website above, website below has details on law about road
traffic and measurements here in the Netherlands:

http://www.stillerverkeer.nl.

Now me go check that out !

(I am getting there... I am getting there... I hope LOL)

Bye,
Skybuck.


Skybuck Flying

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Aug 30, 2009, 2:04:47 AM8/30/09
to
Hmm... I forgot it's sunday... I love sundays, especially when there is no
market... nice and quiet... bad thing is shops closed though... so it has
ups and down :P**** LOL.

But today I don't like it lol... just kidding still love it... peacefull and
quiet at least right now.. ;) :)

But I was hoping to do some measurements... but that will have to wait until
monday and other days when there is a shitload of traffic going on ! ;)

But for now this gives me time to prepare for * THE MEASUREMENT *

A Skybuck movie/thriller coming to your cinema's SOON !! ;) =D

Bye,
Skybuck =D


Skybuck Flying

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Aug 30, 2009, 2:14:42 AM8/30/09
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Ok,

Starting with the fricking basics ;)

What is a microphone ;)

http://en.wikipedia.org/wiki/Microphone

LOL this gonna take a while LOL.

But not really I am speedy reader LOL.

I just read most important/interesting parts for now otherwise I could
indeed be spending a lifetime on this ;)

Bye,
Skybuck.


Skybuck Flying

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Aug 30, 2009, 2:29:19 AM8/30/09
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I found another little bit of interesting information about the microphone
that came with the receiver...

The manual says it was calibrated.

It doesn't say how it was calibrated.

I now go send a e-mail to denon and maybe the original manufacturer... to
see if they want to supply some information about it...

Might come in handy ?! ;)

Bye,
Skybuck.


Skybuck Flying

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Aug 30, 2009, 2:46:05 AM8/30/09
to
Hmm indeed... I didn't look at your links yet... but I also found one which
you also found but a different one, this one for sensitivity of microphone:

http://www.sengpielaudio.com/calculator-transferfactor.htm

Yours was this one:

http://www.sengpielaudio.com/calculator-db-volt.htm

Hmmm so many links, so much reading to do woooooooow.

Gives me the feeling of "how human beings can make something apperently
simple as "sound" into something very complex ?! ;)"

But maybe sound is very complex ! Think of all the molecules bumping against
each other ! LOL.

It's at least a 3D problem ! ;)

At the time factor to it... and it becomes pretty much a 4D factor since
every molecule can have it's own timing in a way ;)

And then add some... for electronics and chemicals/signals in brain and
woooow ;) :)

Bye,
Skybuck.


Skybuck Flying

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Aug 30, 2009, 3:03:45 AM8/30/09
to

"Skybuck Flying" <Blood...@hotmail.com> wrote in message
news:a7433$4a99e6a7$d53372a9$27...@cache2.tilbu1.nb.home.nl...

> Hello,
>
> I have two microphones:
>
> 1. A Fica CMP-202 computer microphone.

Here you can see the Fico in action ;) (It's Fico not Fica... hehe bad font
! ;))

http://samods.org/voicerecord

For a picture of the second mic I'll probably have to put up a picture
myself...

So this could be a good reason to post pictures of my receiver after all...

But this time I will probably scale down the pictures.

The webdrives are not ready yet for +1 MB pictures ! ;)

Also it depends on if microsoft sky drive allows easy viewing of pictures...
I know uploading will probably be a bitch... but maybe it has improved
now... maybe it has ftp support... that would be reaaal nice and easy ;)

Bye,
Skybuck.


Skybuck Flying

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Aug 30, 2009, 5:23:32 AM8/30/09
to
Ok,

I just did my first recording of the outside...

I am kinda curious...

Also first I am gonna have some theeeeaaaa...

And then I am going to amplify the sound... so that you guys can simply hear
it...

And then I am gonna convert it to an mp3 maybe so that it's small in size...
and so that everybody can listen to it...

And then I am going to place it on a website... so that the whole world can
hear what I hear...

Maybe it will put the local "goverment" to shame ! ;) :) LOL.

And remember this is on a sunday morning at 11:21 am LOL.

And this pretty much happens every minute... I recorded two minutes ! ;)

(Monday, Tuesday, Wednesday, Thursday, Friday, And Saturday are going to be
blast !)

Yes ladies and gentlemen this is going to be my BLOG and SOUNDWALL OF SHAME
! =D ;)

Bye,
Skybuck.


Skybuck Flying

unread,
Aug 30, 2009, 5:25:43 AM8/30/09
to
Also this first recording was with the microphone on the ground behind the
balkony wall...

(I haven't listened to the recording yet... but I bet it might have even
been better if it was on the wall instead of behind it but ok).

For next recordings I will see if I can maybe place it somewhere... maybe
stick it to the glass... maybe use a chair... or maybe an extension cord
(but I probably don't have that... but I ll find a way... probably sticky
tape ;) :))

So I should do a new recording with the sticky tape... but for the fun of
it... I want the very very very first recording to be up there as well ;) :)
Kinda funny.

Bye,
Skybuck.


Skybuck Flying

unread,
Aug 30, 2009, 5:35:40 AM8/30/09
to
Ok,

This was an interesting test, some things noticed:

1. First of all there was some wind being picked up by the mic.

2. The mic is also directly placed into the "air stream"... I am venting my
place.. so this might not be a good thing.

3. The wind was modest and layed down for some parts of the recording.

4. The motor cycle accelerating is clearly hearable.

5. The bus accelerating is very clearly hearable and noisy.

6. Cars clearly hearible...

The sound recording for what I am used to is pretty boring but maybe you
guys gonna have a good laugh or gonna find it interesting lol...

I am unsure how to modify it properly for a fair playback... twice change
volume at 20 points might be a bit over the top.... especially for the bus
section.

But 20 plus 15 or so.. or maybe 20 + 10 or so is just about right.

7. This does make the wind excessively large... but hopefully you guys know
it's just wind and can be ignored.

Now the question is: Do I really need to buy a special mic just to get rid
of the wind ?

The answer is: Maybe not... maybe I can "invent"/"think up" some enclosure
for the mic that would keep the wind out a bit ! ;)

^ Interesting.

I should definetly do so more recordings... but the city is slowly waking up
even on Sunday...

But that's the way it is... I am not gonna hide the thruth... no people... I
am going to record the thruth and put it out there... no matter how painfull
it might be ! LOL.

Actually I already heard two interesting motor engines this morning as I
placed the mic... one strange car sound (not on recording)... one
accelerating crazy bike... and ofcourse the boring dreaded busses... well
boring for me... maybe not so boring for you ;)

Bye,
Skybuck.


Skybuck Flying

unread,
Aug 30, 2009, 6:07:27 AM8/30/09
to
Hmm...

I might have to stop drinking hot thea altogether if I don't want to die
from "swallow" cancer...

Normally I eat bread with thea... but not this time...

For the first time I could actually feel my throat hurting a bit after the
first two nips...

I put a finger in the thea and it was fricking hot... and then I drink it
and it feels normal in my mouth/tong... that means my mouth and tong have
been burned too many times I think...

Even after pooring louds of cold water in it it was still way too hot
according to my fingers... and my mouth thought it was kinda luke-warm...

This is not a good sign... sigh... but what else can I drink ? Not much...

1. Water contaminated with medicines and other chemicals.

2. Drinks bad for health because of synthetic sugars and conservitives.

3. Milk is jacky and also contains way to many cancerous steriouds and what
not ;)
Dirty farmers ! HAHA SUCK IT AND DIE FOR IT. And that doesn't even include
the chinese scandal ! ;) :) LOL.

4. I could try drinking blood and become a vampire... but even human beings
seem to be contaminated ! BLEH :P.

5. I don't trust spring-water from the supermarket it's probably just water
from the tap :).

6. Boiling water probably don't help much and then there's the heath
problem... and just plain water a bit tasteless... can't add flavors from
supermarket since those contaminated as well/bad chemicals.

7. Hmm I just had an idea... maybe I can create my own flavors... but I just
remembed what I could drink: apple juice ! But carefull... they might lie
about what's in it...

8. So the idea I had was: Buy Banana's, Buy Apples, Buy Lemons... Buy all
kinds of fruit and make your/my own juicy. But I did hear banana's where
also being fed hermons/sort of steroids to get them from green to yellow.
Apples could have pesticides... but maybe only the shell ?... Don't know
about lemons ;) Strawberries ? Drapes... those could be mutated to make them
pitless ;)

Yup poor state we are in me thinks ;)

Bye,
Skybuck.


Skybuck Flying

unread,
Aug 30, 2009, 6:24:02 AM8/30/09
to
Now the problem probably is that the scale in GoldWave doesn't mean much.

The problem also seems to be too many volume controls...

These could be seperated into:

1. Input volume controls.
2. Output volume controls.

The soundblaster/and/or windows has an input volume control for the mic...
during the recording it was a bit on low... about 25% or so I think... I am
not sure if this influences the recording but I would think so... so I would
have to re-test this again... but not gonna go through all the trouble of
going outside...

I am just gonna do some inside tests to see how much that makes an
influences on the recording... but I did do some recordings in the past with
the other fico mic... and I know it matters at least for realtime... so
probably also for recordings... there is also a mic boost which would again
change the scale/volume.

Then for playback there is also the volume issue... multiple volume
controls...

1. Receiver volume control
2. Soundblaster/and/or/windows volume control.
3. Player volume control like youtube or winamp.

For analyses purposes getting a grip on the input volume control would be a
good step in the correct direction.

What I probably need now is:

1. Information about the mic... what kind of recordings does it make ?

2. Maybe also some information about the soundblaster as the other guy
said... does the soundblaster do any amplification... how about windows ?
What to set the mic too...
Could get kinda complex.

See here I see how buying a seperate device might take care of all of
that... but then I would be mostly paying for a configuration issue... and
how do I know for sure if it was properly configured/calibrated ?!? Trust is
in the toilet these days so I can't trust anybody selling anything.

Bye,
Skybuck.

Skybuck Flying

unread,
Aug 30, 2009, 6:24:51 AM8/30/09
to
"Skybuck Flying" <Blood...@hotmail.com> wrote in message
news:bac59$4a9a533e$d53372a9$21...@cache4.tilbu1.nb.home.nl...

I guess I am saying... I need certain garantuees ! Yeah baby ! ;)

Bye,
Skybuck =D


Nick Cramer

unread,
Aug 31, 2009, 5:38:26 AM8/31/09
to
"Skybuck Flying" <Blood...@hotmail.com> wrote:
> Hello,
>
> I have two microphones:
>
> 1. A Fica CMP-202 computer microphone.
>
> (I got it for free a long time ago from somebody.)
>
> 2. A Pyramid/Pole like microphone DM-A409 that came with my 7.1 Receiver
> (Denon AVR 1909).
>
> (Bought this recently... seems quite an impressive microphone according
> to some charts it was able to capture ?)
>
> Anyway I was wondering if these microphones are suited to do certain
> sound measurements in either Db(A) or Db(C). (Maybe use GoldWave for
> analyses ?)
>
> I want to measure the sound level that is coming from the
> cars/trucks/busses outside.
> (I want to measure the sound level outside and inside my living room).
>
> Would these microphones be suited for the task do you think ?
>
> I was also considering buying a special microphone like this one:
>
> http://www1.conrad.nl/scripts/wgate/zcop_nl3/~flN0YXRlPTE5MDM3OTk1OTk=?di
> rekt_aufriss_area=SHOP_B2C_Metering&~template=PCAT_AREA_S_browse&p_page_t
> o_display=&catalogs_sub_id=sub12&aktiv=12&navi=oben_1
>
> Product is called: "SL-400 decibelmeter " (in dutch)
>
> Suppose the answer would be: "No your current microphones are not suited
> for the task..."
>
> then I wonder what would be the difference between these microphones and
> a specialized microphone ?
>
> Can anybody explain ?

http://www.digital-recordings.com/audiocd/radio.html

Radio Shack meter is $50.

--
Nick, KI6VAV. Support severely wounded and disabled Veterans and their
families: https://www.woundedwarriorproject.org/ Thank a Veteran!
Support Our Troops: http://anymarine.com/ You are not forgotten.
Thanks ! ! ~Semper Fi~ USMC 1365061

Skybuck Flying

unread,
Aug 31, 2009, 6:37:08 PM8/31/09
to
The e-mail replay from a Denon employee is funny:

"
The microphone is specifically calibrated to read the Audyssey tone from
the particular receiver it is supplied with. It is not designed to
record sound or to be used for any other purpose.
"

^^^ Wacky ^^^ :)

I could record the "Audyssey tone" would that do any good ?

Should I record it with the mic itself or another mic... would that make any
difference ?

Hmmmmmmmmmmmmm...

(The mic is clearly able to record any form of sound so what Denon wrote is
a bit whack ! :))

Bye,
Skybuck.


Skybuck Flying

unread,
Aug 31, 2009, 6:38:44 PM8/31/09
to
Well I am not letting them off the hook so easily ?! ;) :)

I am going to ask them if they can sent me the "wave" file for the tone...

Maybe it would be of sum use ! ;)

Bye,
Skybuck.


Skybuck Flying

unread,
Aug 31, 2009, 6:42:30 PM8/31/09
to
This is what I wrote back:

"
Hello,

It may not have been designed for any other purpose... but that doesn't mean
that it couldn't be used for it.

I would be interested in receiving a wave file for the Audyssey tone... it
might be of some use... For example comparing the original audyssey
tone/wave file with the one recorded by the mic.

The mic can be attached to my pc/soundblaster so then I can analyze waves
with goldwave editor (software).

Bye,
Skybuck.
"

Nice isn't it ? ;) :)

(Psychological spin BABY ! =D LOL)

Bye,
Skybuck =D


Arny Krueger

unread,
Sep 1, 2009, 9:33:00 AM9/1/09
to
"Skybuck Flying" <Blood...@hotmail.com> wrote in message
news:cd981$4a9c508d$d53372a9$25...@cache3.tilbu1.nb.home.nl

I suspect that more likely, the Denon reciever is calibrated for the mic
that ships with it.


V__i___n_ce__19_7_1_

unread,
Sep 2, 2009, 10:06:39 AM9/2/09
to
Pls stop spamming the dutch ng with your idiot talk

ik

unread,
Sep 4, 2009, 11:51:39 AM9/4/09
to
er kunnen veel strondvliegen op een hoop strond.

"Nick Cramer" <n_cram...@pacbell.net> schreef in bericht
news:20090831053409.798$w...@newsreader.com...

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