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Igor (t4a) Igor (t4a) is offline
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Default Argument against room noise?


I decided to start a new thread because it has not much to do with my
attempts pretending to be a talent. ;-)

Since I have heard it so often that if there is noise it is from the
room and so forth here is an interesting experiment.

It is a comparison between an RE-20 (150 Ohms) and an Shure Beta 50A
(270 Ohms).

First of all, theoretically in a total quiet room with no air in it,
e.g. in space, the Sure Beta should create more noise (at a
temperature above 0 Kelvin).

Further, if the room were noisy the Shure Beta should be noisier
because it would pick up the noise much louder.

So far, so good.

Now listen to that file. Both microphones were connected to the same
(self-built) pre-amp at a gain of about 58.5 dB.

Content:
quiet room with RE-20 - attention a control tone for loudness
evalution is also in there
quiet room with Sure Beta 58A - attention a control tone for loudness
evalution is in there
quiet room with RE-20: the unbalanced audio cable to the computer was
placed differently here - apparently there is much less 50 Hz noise
now, but much more 100 Hz hum, oh well ...

http://download.yousendit.com/E0DCA8587A3F6746

1.3 MB

Just to give you an impression I sent a control tone from an
electronic toy to demonstrate that the pickup level of the Sure Beta
is much higher (same distance - I know that this is no precise method
to do it.)

Anyway, I would say after that recording there wouldn't be many
arguments left for a noisy room, would there?

What _is_ wrong here? Any idea?

Best wishes,
Igor

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Mark Mark is offline
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Default Argument against room noise?

On Oct 24, 4:09 pm, "Igor (t4a)" wrote:
I decided to start a new thread because it has not much to do with my
attempts pretending to be a talent. ;-)

Since I have heard it so often that if there is noise it is from the
room and so forth here is an interesting experiment.

It is a comparison between an RE-20 (150 Ohms) and an Shure Beta 50A
(270 Ohms).

First of all, theoretically in a total quiet room with no air in it,
e.g. in space, the Sure Beta should create more noise (at a
temperature above 0 Kelvin).

Further, if the room were noisy the Shure Beta should be noisier
because it would pick up the noise much louder.

So far, so good.

Now listen to that file. Both microphones were connected to the same
(self-built) pre-amp at a gain of about 58.5 dB.

Content:
quiet room with RE-20 - attention a control tone for loudness
evalution is also in there
quiet room with Sure Beta 58A - attention a control tone for loudness
evalution is in there
quiet room with RE-20: the unbalanced audio cable to the computer was
placed differently here - apparently there is much less 50 Hz noise
now, but much more 100 Hz hum, oh well ...

http://download.yousendit.com/E0DCA8587A3F6746

1.3 MB

Just to give you an impression I sent a control tone from an
electronic toy to demonstrate that the pickup level of the Sure Beta
is much higher (same distance - I know that this is no precise method
to do it.)

Anyway, I would say after that recording there wouldn't be many
arguments left for a noisy room, would there?

What _is_ wrong here? Any idea?

Best wishes,
Igor


are you in the UK?
50 and 100 Hz noise is certainly either electrical from the mains (as
you call them) or acoustical from a motor or humming transformer or ??

is the computer in the room?
with a fan?
does it make any noise?

you say its a homemade pre-amp?

Is it a transformer coupled input? is it magnetically shielded with
mu metal?
whats the common mode rejection?
Can you try another pre-amp?

Is there anything nearby radiating an AC magnetic field...again motor
or transfomer,,,
one of those low voltage desk lamps with a transformer in the base?
a CLOCK?
a UPS?
a wall wart?
etc etc...

put on headphones, crank up the gain and move the mic and cable around
and see what makes it louder and softer.

Mark



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Mike Rivers Mike Rivers is offline
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Default Argument against room noise?

On Oct 24, 4:09 pm, "Igor (t4a)" wrote:

Just to give you an impression I sent a control tone from an
electronic toy to demonstrate that the pickup level of the Sure Beta
is much higher (same distance - I know that this is no precise method
to do it.)

Anyway, I would say after that recording there wouldn't be many
arguments left for a noisy room, would there?


All of this nonsense about 150 ohms and 270 ohms and absolute zero
aside, what you've demonstrated, I think, is that the Shure mic is
more sensitive than the EV.

Anything that you don't want to record is noise. It's better not to
have any. It should be made illegal and, if caught, sent directly to
jail without passing Go or collecting $200.

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[email protected] rsmith@bsstudios.com is offline
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Default Argument against room noise?

On Oct 24, 12:09 pm, "Igor (t4a)" wrote:
I decided to start a new thread because it has not much to do with my
attempts pretending to be a talent. ;-)

Since I have heard it so often that if there is noise it is from the
room and so forth here is an interesting experiment.

It is a comparison between an RE-20 (150 Ohms) and an Shure Beta 50A
(270 Ohms).

First of all, theoretically in a total quiet room with no air in it,
e.g. in space, the Sure Beta should create more noise (at a
temperature above 0 Kelvin).

Further, if the room were noisy the Shure Beta should be noisier
because it would pick up the noise much louder.

So far, so good.

Now listen to that file. Both microphones were connected to the same
(self-built) pre-amp at a gain of about 58.5 dB.

Content:
quiet room with RE-20 - attention a control tone for loudness
evalution is also in there
quiet room with Sure Beta 58A - attention a control tone for loudness
evalution is in there
quiet room with RE-20: the unbalanced audio cable to the computer was
placed differently here - apparently there is much less 50 Hz noise
now, but much more 100 Hz hum, oh well ...

http://download.yousendit.com/E0DCA8587A3F6746

1.3 MB

Just to give you an impression I sent a control tone from an
electronic toy to demonstrate that the pickup level of the Sure Beta
is much higher (same distance - I know that this is no precise method
to do it.)

Anyway, I would say after that recording there wouldn't be many
arguments left for a noisy room, would there?

What _is_ wrong here? Any idea?

Best wishes,
Igor


Igor, you have at least three distinct noise types in that recording.
There is a constant thub-thub-thub occuring at approximately 0.5
second intervals which I believe to be residual noise leaking into
your room, there is a residual mains hum which is probably electrical
in nature though it could be acoustic pickup, and then the residual
hiss of your preamp noise floor. If one of my voiceover talents had
submitted that it would have been rejected as too noisy. You need a
lower noise floor preamp for the RE20 to give you its best or to get
close to the mic and talk with higher sound levels.

bobs

Bob Smith
BS Studios
we organize chaos
http://www.bsstudios.com

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Igor (t4a) Igor (t4a) is offline
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Default Argument against room noise?

On 24 Okt., 23:29, Mark wrote:
On Oct 24, 4:09 pm, "Igor (t4a)" wrote:
...

are you in the UK?


(Electrically) close: Germany.

50 and 100 Hz noise is certainly either electrical from the mains (as
you call them) or acoustical from a motor or humming transformer or ??


Certainly. I think I can blame the housing of my pre-amp. I am also
not certain if it is wise to use a 15m _unbalanced_ cable to connect
pre-amp and soundcard. Unfortunatly, the sound card M-Audio Audiophile
2496 has only unbalanced inputs and was originally bought to take an
AES-signal. But things have changed faster than I expected.

is the computer in the room?
with a fan?
does it make any noise?


It is far, far away. There are three doors (in no direct line) between
the recording room and the computer.

you say its a homemade pre-amp?


Yep. However, I tested others as well. I think I'll rent an
"expensive" one day but I am not too sure, if that will solve the
problems I'm having.

Is it a transformer coupled input? is it magnetically shielded with
mu metal?


No. INA 217.

whats the common mode rejection?
Can you try another pre-amp?


Yes.

Is there anything nearby radiating an AC magnetic field...again motor
or transfomer,,,


Power lines. Apart from that - no. I am not sure, if it is conducted
noise somehow. I use a "normal" mike-stand with a clip adapter.

one of those low voltage desk lamps with a transformer in the base?


No.

a CLOCK?


No.

a UPS?


No.

a wall wart?


No.

etc etc...


Well, I know it must be something. However, calculations with the
thermal noise of a 150 Ohm source and 60 dB amplification clearly lead
in neighbourhood of the appearant noise.

Frankly, apart from the obvious interferences by mains hum and the
second and third harmonics, I think the noise level is there where it
should be. My impression is that the _signal_ is too low.

put on headphones, crank up the gain and move the mic and cable around
and see what makes it louder and softer.


I will..

Thank you, Mark. It looks as if it will take longer than expected and
will cost more than anticipated. ;-)

Best wishes,
Igor



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Igor (t4a) Igor (t4a) is offline
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Default Argument against room noise?

On 25 Okt., 04:06, wrote:
On Oct 24, 12:09 pm, "Igor (t4a)" wrote:


...

Igor, you have at least three distinct noise types in that recording.
There is a constant thub-thub-thub occuring at approximately 0.5
second intervals which I believe to be residual noise leaking into
your room, there is a residual mains hum which is probably electrical
in nature though it could be acoustic pickup, and then the residual
hiss of your preamp noise floor.


Thank you, Bob. Nobody claimed that there is noise in that recording.
The point is why does the Shure not pick up the noise louder? My
deduction was that it is not of acoustic origin. No doubt that it is
of some origin (magnetic, conducted, electromagnetic, electric
field ... ) and I trying to find out, if my reasoning by directly
comparing two microphones with obviously different sensitivities,
could back up this claim.

If one of my voiceover talents had
submitted that it would have been rejected as too noisy. You need a
lower noise floor preamp for the RE20 to give you its best or to get
close to the mic and talk with higher sound levels.


Bob, I am more than aware that this noise floor is unacceptable.
However, I still follow the approach of miking at a "pleasant"
distance and wonder where I could end. BTW, I do not intend to use my
recordings commercially. ;-)

Best wishes,
Igor

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Default Argument against room noise?

On 25 Okt., 00:12, Mike Rivers wrote:
On Oct 24, 4:09 pm, "Igor (t4a)" wrote:

...
Anyway, I would say after that recording there wouldn't be many
arguments left for a noisy room, would there?


All of this nonsense about 150 ohms and 270 ohms and absolute zero
aside, what you've demonstrated, I think, is that the Shure mic is
more sensitive than the EV.


My point was, if the noise stems from acoustic origins than the Shure
should have picked it up _louder_. Appearantly this was not the case.

Anything that you don't want to record is noise. It's better not to
have any. It should be made illegal and, if caught, sent directly to
jail without passing Go or collecting $200.


Mike, I think you agree that noise is part of the physical reality.
Therefore you could go after signal/noise-ratio violations but not
after noise itself.

Best wishes,
Igor

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Igor (t4a) Igor (t4a) is offline
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Default Argument against room noise?

Igor (t4a) wrote:
...
Nobody claimed that there is noise in that recording.


Oops, I seem to be still in the first stage of the realization
process: denial. ;-)

It should read:

Nobody claimed that there is no noise in that recording.

Best wishes,
Igor

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Mike Rivers Mike Rivers is offline
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Default Argument against room noise?

On Oct 25, 4:21 am, "Igor (t4a)" wrote:

Mike, I think you agree that noise is part of the physical reality.
Therefore you could go after signal/noise-ratio violations but not
after noise itself.


There's electrical noise, and then there's acoustic noise. Both
contribute to the signal-to-noise ratio of your final product. Both
can be addressed, but in different ways, and with different levels of
success. The microphone itself, since it's a transducer, contributes
to both the electrical and acoustic noise.

You can (and have) determine the electrical noise floor by measuring
what comes out of the preamp with no electrical signal going in.
Replacing the microphone with a 150 ohm resistor isn't to simulate
Browinian noise, it's (oversimplified explanation warning!) because
the input transistor has current noise and needs something across
which to develop a voltage that can be amplified. This is why there's
about a 3 dB difference between the preamp output noise with a 150 ohm
resistor at the input and with a short circuit at the input. If you
could put the microphone in a very soundproof enclosure and connect it
to the input, you'd see output noise close to that which you get with
the 150 ohm resistor. You might be able to get a little quieter than
this, but not much.

There are other sources of electrical noise other than "hiss." These
are things that you can fix. You can eliminate hum from the power
supply (try running your preamp on batteries). You can use balanced
wiring to minimize common mode hum and noise pickup in the cables. You
can put it in a well shielded box to keep stray RF out of the
innards.

As far as acoustic noise that the microphone picks up, the easiest way
to deal with that is to move to somewhere quiet. You can turn off all
noisemakers and isolate it from mechanical vibration.

But, as you surmised, it's not just about quiescent noise, the quality
of your final product is about signal-to-noise ratio. You can fix this
by putting more signal into the amplifier input. You can do this by
getting closer to the mic, or by using a more sensitive mic - one that
generates a higher voltage for the same sound level. If you don't like
how the mic sounds (and can't satisfactorily adjust it) then you need
a different mic. Try an omni. This will have negligible proximity
effect, but the tradeoff is that it will pick up more of the
refrigerator running in the kitchen or the truck driving by outside.
You just need to find the right compromise.

Alternately, you can just speak louder. More acoustic energy going
into the mic will result in more volts coming out, which will allow
you to reduce the preamp gain, which will reduce the electrical noise.
It will also bring the level of your voice at the microphone further
above the acoustic noise level at the mic, further improving the
signal-to-noise ratio.

So, you just have to do something. This won't get better on its own.

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Igor (t4a) Igor (t4a) is offline
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Default What gain do you use with dynamic mics? was Argument against room noise?

On 25 Okt., 13:08, Mike Rivers wrote:
On Oct 25, 4:21 am, "Igor (t4a)" wrote:

Mike, I think you agree that noise is part of the physical reality.
Therefore you could go after signal/noise-ratio violations but not
after noise itself.


There's electrical noise, and then there's acoustic noise. Both
contribute to the signal-to-noise ratio of your final product. Both
can be addressed, but in different ways, and with different levels of
success. The microphone itself, since it's a transducer, contributes
to both the electrical and acoustic noise.

You can (and have) determine the electrical noise floor by measuring
what comes out of the preamp with no electrical signal going in.
Replacing the microphone with a 150 ohm resistor isn't to simulate
Browinian noise, it's (oversimplified explanation warning!) because
the input transistor has current noise and needs something across
which to develop a voltage that can be amplified. This is why there's
about a 3 dB difference between the preamp output noise with a 150 ohm
resistor at the input and with a short circuit at the input. If you
could put the microphone in a very soundproof enclosure and connect it
to the input, you'd see output noise close to that which you get with
the 150 ohm resistor. You might be able to get a little quieter than
this, but not much.

There are other sources of electrical noise other than "hiss." These
are things that you can fix. You can eliminate hum from the power
supply (try running your preamp on batteries). You can use balanced
wiring to minimize common mode hum and noise pickup in the cables. You
can put it in a well shielded box to keep stray RF out of the
innards.

As far as acoustic noise that the microphone picks up, the easiest way
to deal with that is to move to somewhere quiet. You can turn off all
noisemakers and isolate it from mechanical vibration.

But, as you surmised, it's not just about quiescent noise, the quality
of your final product is about signal-to-noise ratio. You can fix this
by putting more signal into the amplifier input. You can do this by
getting closer to the mic, or by using a more sensitive mic - one that
generates a higher voltage for the same sound level. If you don't like
how the mic sounds (and can't satisfactorily adjust it) then you need
a different mic. Try an omni. This will have negligible proximity
effect, but the tradeoff is that it will pick up more of the
refrigerator running in the kitchen or the truck driving by outside.
You just need to find the right compromise.

Alternately, you can just speak louder. More acoustic energy going
into the mic will result in more volts coming out, which will allow
you to reduce the preamp gain, which will reduce the electrical noise.
It will also bring the level of your voice at the microphone further
above the acoustic noise level at the mic, further improving the
signal-to-noise ratio.

So, you just have to do something. This won't get better on its own.


Thank you very much, Mike, I work on the problem, believe me.

After thinking some more I realized that I can even rephrase the
problem to the following question:

What gain setting do you use when you record someone with an RE-20 (or
some other dynamic mic).

Maybe the answer to this question can shed some light on the problem.
Do you actually run pre-amps at 60 dB gain and higher gains getting
signals with peaks at -9dB and less?

Thanks again.

Best wishes,
Igor



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Don Pearce Don Pearce is offline
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Default What gain do you use with dynamic mics? was Argument against room noise?

On Thu, 25 Oct 2007 04:29:13 -0700, "Igor (t4a)" wrote:

Thank you very much, Mike, I work on the problem, believe me.

After thinking some more I realized that I can even rephrase the
problem to the following question:

What gain setting do you use when you record someone with an RE-20 (or
some other dynamic mic).

Maybe the answer to this question can shed some light on the problem.
Do you actually run pre-amps at 60 dB gain and higher gains getting
signals with peaks at -9dB and less?

Thanks again.

Best wishes,
Igor


Remember that the gain comes in two parts, which must be added
together. First is the gain you dial into the preamp. Next is whatever
normalization gain you use in the DAW to remove all the headroom you
allowed in making the recording.

d

--
Pearce Consulting
http://www.pearce.uk.com
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Mark Mark is offline
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Default Argument against room noise?

On Oct 24, 10:06 pm, wrote:
On Oct 24, 12:09 pm, "Igor (t4a)" wrote:





I decided to start a new thread because it has not much to do with my
attempts pretending to be a talent. ;-)


Since I have heard it so often that if there is noise it is from the
room and so forth here is an interesting experiment.


It is a comparison between an RE-20 (150 Ohms) and an Shure Beta 50A
(270 Ohms).


First of all, theoretically in a total quiet room with no air in it,
e.g. in space, the Sure Beta should create more noise (at a
temperature above 0 Kelvin).


Further, if the room were noisy the Shure Beta should be noisier
because it would pick up the noise much louder.


So far, so good.


Now listen to that file. Both microphones were connected to the same
(self-built) pre-amp at a gain of about 58.5 dB.


Content:
quiet room with RE-20 - attention a control tone for loudness
evalution is also in there
quiet room with Sure Beta 58A - attention a control tone for loudness
evalution is in there
quiet room with RE-20: the unbalanced audio cable to the computer was
placed differently here - apparently there is much less 50 Hz noise
now, but much more 100 Hz hum, oh well ...


http://download.yousendit.com/E0DCA8587A3F6746


1.3 MB


Just to give you an impression I sent a control tone from an
electronic toy to demonstrate that the pickup level of the Sure Beta
is much higher (same distance - I know that this is no precise method
to do it.)


Anyway, I would say after that recording there wouldn't be many
arguments left for a noisy room, would there?


What _is_ wrong here? Any idea?


Best wishes,
Igor


Igor, you have at least three distinct noise types in that recording.
There is a constant thub-thub-thub occuring at approximately 0.5
second intervals which I believe to be residual noise leaking into
your room, there is a residual mains hum which is probably electrical
in nature though it could be acoustic pickup, and then the residual
hiss of your preamp noise floor. If one of my voiceover talents had
submitted that it would have been rejected as too noisy. You need a
lower noise floor preamp for the RE20 to give you its best or to get
close to the mic and talk with higher sound levels.

bobs

Bob Smith
BS Studios
we organize chaoshttp://www.bsstudios.com- Hide quoted text -

- Show quoted text -


I have to agree with this..there are 2 or 3 seperate noises...if you
are just looking at a VU meter or something equivalent, it will
respond to the sum and it will be very difficult to figure out what is
going on with any one particular noise. I suggest again using
earphones or an RTA and analyze each noise seperatly.

I hear and see on an RTA:

1)what sounds like a mechanical hum maybe conducted via the table.
2)an electical hum (maybe the same as 1)
3) a wideband hiss, almost certainly this is the noise of the pre-amp.

These are 2 or 3 seperate issues.

Mark



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Richard Crowley Richard Crowley is offline
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Default Argument against room noise?

"Igor (t4a)" wrote ...
My point was, if the noise stems from acoustic origins than the Shure
should have picked it up _louder_. Appearantly this was not the case.


But you are also making the assumption that both mics
have the same directional coverage/sensitivity. I believe this
is not the case.

Remember that there more factors than you are isolating
with your home experiments. The combination of the RE20
and your home-made preamp and your recording space may
just not be up to your desired standards. For example, what
is the noise floor in your recording chain if you substitute a
load resistor for your home-made preamp? etc. etc.
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Default What gain do you use with dynamic mics? was Argument against room noise?

On Oct 25, 3:29 am, "Igor (t4a)" wrote:
On 25 Okt., 13:08, Mike Rivers wrote:





On Oct 25, 4:21 am, "Igor (t4a)" wrote:


Mike, I think you agree that noise is part of the physical reality.
Therefore you could go after signal/noise-ratio violations but not
after noise itself.


There's electrical noise, and then there's acoustic noise. Both
contribute to the signal-to-noise ratio of your final product. Both
can be addressed, but in different ways, and with different levels of
success. The microphone itself, since it's a transducer, contributes
to both the electrical and acoustic noise.


You can (and have) determine the electrical noise floor by measuring
what comes out of the preamp with no electrical signal going in.
Replacing the microphone with a 150 ohm resistor isn't to simulate
Browinian noise, it's (oversimplified explanation warning!) because
the input transistor has current noise and needs something across
which to develop a voltage that can be amplified. This is why there's
about a 3 dB difference between the preamp output noise with a 150 ohm
resistor at the input and with a short circuit at the input. If you
could put the microphone in a very soundproof enclosure and connect it
to the input, you'd see output noise close to that which you get with
the 150 ohm resistor. You might be able to get a little quieter than
this, but not much.


There are other sources of electrical noise other than "hiss." These
are things that you can fix. You can eliminate hum from the power
supply (try running your preamp on batteries). You can use balanced
wiring to minimize common mode hum and noise pickup in the cables. You
can put it in a well shielded box to keep stray RF out of the
innards.


As far as acoustic noise that the microphone picks up, the easiest way
to deal with that is to move to somewhere quiet. You can turn off all
noisemakers and isolate it from mechanical vibration.


But, as you surmised, it's not just about quiescent noise, the quality
of your final product is about signal-to-noise ratio. You can fix this
by putting more signal into the amplifier input. You can do this by
getting closer to the mic, or by using a more sensitive mic - one that
generates a higher voltage for the same sound level. If you don't like
how the mic sounds (and can't satisfactorily adjust it) then you need
a different mic. Try an omni. This will have negligible proximity
effect, but the tradeoff is that it will pick up more of the
refrigerator running in the kitchen or the truck driving by outside.
You just need to find the right compromise.


Alternately, you can just speak louder. More acoustic energy going
into the mic will result in more volts coming out, which will allow
you to reduce the preamp gain, which will reduce the electrical noise.
It will also bring the level of your voice at the microphone further
above the acoustic noise level at the mic, further improving the
signal-to-noise ratio.


So, you just have to do something. This won't get better on its own.


Thank you very much, Mike, I work on the problem, believe me.

After thinking some more I realized that I can even rephrase the
problem to the following question:

What gain setting do you use when you record someone with an RE-20 (or
some other dynamic mic).

Maybe the answer to this question can shed some light on the problem.
Do you actually run pre-amps at 60 dB gain and higher gains getting
signals with peaks at -9dB and less?

Thanks again.

Best wishes,
Igor- Hide quoted text -

- Show quoted text -


Yes. If you want I can send you a sample recording of voice using an
RE20 into a Sound Devices preamp built into the SD702 recorder. The
mp3 is approximately 387 KB.

bobs

Bob Smith
BS Studios
we organize chaos
http://www.bsstudios.com

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Default Argument against room noise?

On 25 Okt., 16:03, "Richard Crowley" wrote:
"Igor (t4a)" wrote ...

My point was, if the noise stems from acoustic origins than the Shure
should have picked it up _louder_. Appearantly this was not the case.


But you are also making the assumption that both mics
have the same directional coverage/sensitivity. I believe this
is not the case.


It is not the case. However, ambient noise usually does not show a
strong angle gradient. And after all the mics did point in the same
direction. I can point the mikes in different directions and I would
not expect different readings. I mean, I can hear the blood running in
my ears when it is reasonably quiet. Do I need a microphone to tell me
that it is quiet? ;-)

Remember that there more factors than you are isolating
with your home experiments. The combination of the RE20
and your home-made preamp and your recording space may
just not be up to your desired standards.


True. But what noise floor improvements do we discuss here? 6 dB, 10
dB, 20 dB, 30 dB?

For example, what
is the noise floor in your recording chain if you substitute a
load resistor for your home-made preamp? etc. etc.


Hm, can you please rephrase the question. :-)

Best wishes,
Igor



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Igor (t4a) Igor (t4a) is offline
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Default What gain do you use with dynamic mics? was Argument against room noise?

On 25 Okt., 17:10, wrote:
On Oct 25, 3:29 am, "Igor (t4a)" wrote:





On 25 Okt., 13:08, Mike Rivers wrote:


On Oct 25, 4:21 am, "Igor (t4a)" wrote:


Mike, I think you agree that noise is part of the physical reality.
Therefore you could go after signal/noise-ratio violations but not
after noise itself.


There's electrical noise, and then there's acoustic noise. Both
contribute to the signal-to-noise ratio of your final product. Both
can be addressed, but in different ways, and with different levels of
success. The microphone itself, since it's a transducer, contributes
to both the electrical and acoustic noise.


You can (and have) determine the electrical noise floor by measuring
what comes out of the preamp with no electrical signal going in.
Replacing the microphone with a 150 ohm resistor isn't to simulate
Browinian noise, it's (oversimplified explanation warning!) because
the input transistor has current noise and needs something across
which to develop a voltage that can be amplified. This is why there's
about a 3 dB difference between the preamp output noise with a 150 ohm
resistor at the input and with a short circuit at the input. If you
could put the microphone in a very soundproof enclosure and connect it
to the input, you'd see output noise close to that which you get with
the 150 ohm resistor. You might be able to get a little quieter than
this, but not much.


There are other sources of electrical noise other than "hiss." These
are things that you can fix. You can eliminate hum from the power
supply (try running your preamp on batteries). You can use balanced
wiring to minimize common mode hum and noise pickup in the cables. You
can put it in a well shielded box to keep stray RF out of the
innards.


As far as acoustic noise that the microphone picks up, the easiest way
to deal with that is to move to somewhere quiet. You can turn off all
noisemakers and isolate it from mechanical vibration.


But, as you surmised, it's not just about quiescent noise, the quality
of your final product is about signal-to-noise ratio. You can fix this
by putting more signal into the amplifier input. You can do this by
getting closer to the mic, or by using a more sensitive mic - one that
generates a higher voltage for the same sound level. If you don't like
how the mic sounds (and can't satisfactorily adjust it) then you need
a different mic. Try an omni. This will have negligible proximity
effect, but the tradeoff is that it will pick up more of the
refrigerator running in the kitchen or the truck driving by outside.
You just need to find the right compromise.


Alternately, you can just speak louder. More acoustic energy going
into the mic will result in more volts coming out, which will allow
you to reduce the preamp gain, which will reduce the electrical noise.
It will also bring the level of your voice at the microphone further
above the acoustic noise level at the mic, further improving the
signal-to-noise ratio.


So, you just have to do something. This won't get better on its own.


Thank you very much, Mike, I work on the problem, believe me.


After thinking some more I realized that I can even rephrase the
problem to the following question:


What gain setting do you use when you record someone with an RE-20 (or
some other dynamic mic).


Maybe the answer to this question can shed some light on the problem.
Do you actually run pre-amps at 60 dB gain and higher gains getting
signals with peaks at -9dB and less?


Thanks again.


Best wishes,
Igor- Hide quoted text -


- Show quoted text -


Yes. If you want I can send you a sample recording of voice using an
RE20 into a Sound Devices preamp built into the SD702 recorder. The
mp3 is approximately 387 KB.

bobs

Bob Smith
BS Studios
we organize chaoshttp://www.bsstudios.com- Zitierten Text ausblenden -

- Zitierten Text anzeigen -


Yes, plese. I can't wait to listen to your recording. Email has been
sent.

Thank you.

Best wishes,
Igor

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Richard Crowley Richard Crowley is offline
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Default Argument against room noise?

"Igor (t4a)" wrote ...
"Richard Crowley" wrote:
But you are also making the assumption that both mics
have the same directional coverage/sensitivity. I believe this
is not the case.


It is not the case. However, ambient noise usually does not show a
strong angle gradient. And after all the mics did point in the same
direction. I can point the mikes in different directions and I would
not expect different readings. I mean, I can hear the blood running in
my ears when it is reasonably quiet. Do I need a microphone to tell me
that it is quiet? ;-)


If it is that acoustically quiet, and you don't hear any 50/100 Hz
hum, that is a good indication that it is being magnetically
induced (or incompletely filtered from the mains power
supply) rather than an acoustic signal (as from a fluorescent
lamp ballast, etc.)

Remember that there more factors than you are isolating
with your home experiments. The combination of the RE20
and your home-made preamp and your recording space may
just not be up to your desired standards.


True. But what noise floor improvements do we discuss here? 6 dB, 10
dB, 20 dB, 30 dB?


But I'm not sure what your requirements were, exactly?
I personally think your SNR is already good enough for
amateur home-recording, and maybe even limited
commercial work (for some specialty area like reading
for the sight- or movement-impaired, etc.)

Beyond that is this just a scientific experiment to see how
low we can get the noise floor, or is it a practical exercise
to get some speech recorded?

Either way is fine, as long as we know what the goal is here.
Because measuring the SNR is a scientific, objective thing.
But evaluating whether it is "good enough" depends on the
answer to the question: "good enough for *what* exactly"?

If we are just obsessing on "how low can we go", I will leave
it to others as I confess to being an old-school pragmatist.

For example, what
is the noise floor in your recording chain if you substitute a
load resistor for your home-made preamp? etc. etc.


Hm, can you please rephrase the question. :-)


The total noise floor in the system is made up of the
contributions from ALL the links in the chain. Many of
these can be isolated and measured independently in
order to identify the biggest problem (or the most easily
solved.) I was suggesting one experiment that would
get us closer to isolating the main contributor of the noise.



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Richard Crowley Richard Crowley is offline
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Default Argument against room noise?

wrote ...
Igor, you have at least three distinct noise types in that recording.
There is a constant thub-thub-thub occuring at approximately 0.5
second intervals which I believe to be residual noise leaking into
your room, ...


Of course, since we are hearing only MP3-compressed
versions of the original recordings, we also don't know
which artifacts may be a result of the MP3-encoding and
decoding, etc.


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Default What gain do you use with dynamic mics? was Argument against room noise?

On 25 Okt., 17:10, wrote:
On Oct 25, 3:29 am, "Igor (t4a)" wrote:





On 25 Okt., 13:08, Mike Rivers wrote:


On Oct 25, 4:21 am, "Igor (t4a)" wrote:


Mike, I think you agree that noise is part of the physical reality.
Therefore you could go after signal/noise-ratio violations but not
after noise itself.


There's electrical noise, and then there's acoustic noise. Both
contribute to the signal-to-noise ratio of your final product. Both
can be addressed, but in different ways, and with different levels of
success. The microphone itself, since it's a transducer, contributes
to both the electrical and acoustic noise.


You can (and have) determine the electrical noise floor by measuring
what comes out of the preamp with no electrical signal going in.
Replacing the microphone with a 150 ohm resistor isn't to simulate
Browinian noise, it's (oversimplified explanation warning!) because
the input transistor has current noise and needs something across
which to develop a voltage that can be amplified. This is why there's
about a 3 dB difference between the preamp output noise with a 150 ohm
resistor at the input and with a short circuit at the input. If you
could put the microphone in a very soundproof enclosure and connect it
to the input, you'd see output noise close to that which you get with
the 150 ohm resistor. You might be able to get a little quieter than
this, but not much.


There are other sources of electrical noise other than "hiss." These
are things that you can fix. You can eliminate hum from the power
supply (try running your preamp on batteries). You can use balanced
wiring to minimize common mode hum and noise pickup in the cables. You
can put it in a well shielded box to keep stray RF out of the
innards.


As far as acoustic noise that the microphone picks up, the easiest way
to deal with that is to move to somewhere quiet. You can turn off all
noisemakers and isolate it from mechanical vibration.


But, as you surmised, it's not just about quiescent noise, the quality
of your final product is about signal-to-noise ratio. You can fix this
by putting more signal into the amplifier input. You can do this by
getting closer to the mic, or by using a more sensitive mic - one that
generates a higher voltage for the same sound level. If you don't like
how the mic sounds (and can't satisfactorily adjust it) then you need
a different mic. Try an omni. This will have negligible proximity
effect, but the tradeoff is that it will pick up more of the
refrigerator running in the kitchen or the truck driving by outside.
You just need to find the right compromise.


Alternately, you can just speak louder. More acoustic energy going
into the mic will result in more volts coming out, which will allow
you to reduce the preamp gain, which will reduce the electrical noise.
It will also bring the level of your voice at the microphone further
above the acoustic noise level at the mic, further improving the
signal-to-noise ratio.


So, you just have to do something. This won't get better on its own.


Thank you very much, Mike, I work on the problem, believe me.


After thinking some more I realized that I can even rephrase the
problem to the following question:


What gain setting do you use when you record someone with an RE-20 (or
some other dynamic mic).


Maybe the answer to this question can shed some light on the problem.
Do you actually run pre-amps at 60 dB gain and higher gains getting
signals with peaks at -9dB and less?


Thanks again.


Best wishes,
Igor- Hide quoted text -


- Show quoted text -


Yes. If you want I can send you a sample recording of voice using an
RE20 into a Sound Devices preamp built into the SD702 recorder. The
mp3 is approximately 387 KB.

bobs

Bob Smith
BS Studios
we organize chaoshttp://www.bsstudios.com- Zitierten Text ausblenden -

- Zitierten Text anzeigen -



First of all, thank you very much to everyone who cared to answer.

Secondly, despite all the details we discuss here, I must admit that
Bob blew away all my defenses I had erected in the past with the file
he provided. He recorded in his studio on his system using an RE-20 a
testfile at different distances between talent and microphone up to
one foot - and I have to say: wow!

The noise level is _decisively_ lower than my noise level at short
circuit. Now I have no the slightest doubt that the main problem
(apart from others) is the preamp.

Thank you very, very much Bob. This is the way to go.

Best wishes,
Igor

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Default Argument against room noise?

On 25 Okt., 18:41, "Richard Crowley" wrote:
"Igor (t4a)" wrote ...
"Richard Crowley" wrote:
...
...

Do I need a microphone to tell me
that it is quiet? ;-)


If it is that acoustically quiet, and you don't hear any 50/100 Hz
hum, that is a good indication that it is being magnetically
induced (or incompletely filtered from the mains power
supply) rather than an acoustic signal (as from a fluorescent
lamp ballast, etc.)


Yes, I have looked hard already. Somehow I hope that this problem
could be eliminated by a balanced wiring between pre-amp and a
balanced ADC.

Remember that there more factors than you are isolating
with your home experiments. The combination of the RE20
and your home-made preamp and your recording space may
just not be up to your desired standards.


True. But what noise floor improvements do we discuss here? 6 dB, 10
dB, 20 dB, 30 dB?


But I'm not sure what your requirements were, exactly?
I personally think your SNR is already good enough for
amateur home-recording, and maybe even limited
commercial work (for some specialty area like reading
for the sight- or movement-impaired, etc.)


I would have even accepted this answer until I listened to Bob's file.
It is such a huge difference, he has roughly a 10 dB lower noise
floor. Although it is difficult to compare, the difference between his
signal to noise and mine is enormous.

Beyond that is this just a scientific experiment to see how
low we can get the noise floor, or is it a practical exercise
to get some speech recorded?


The latter. ;-) I just would have never expected until I started with
this how incredibly difficult it is. My initial thoughts were that
with some maybe even semi-professional equipment I could record
decently nowadays. I am still surprised at the huge amount of
knowledge and partly special hardware that is necessary. Somehow, I
slowly realize that the war against the room noise was the wrong
battlefield. I could have done half of it to find out that the
problems come from other sources ...

Either way is fine, as long as we know what the goal is here.
Because measuring the SNR is a scientific, objective thing.
But evaluating whether it is "good enough" depends on the
answer to the question: "good enough for *what* exactly"?


Let's call it "CD-quality". I have found an unprecise but useful
definition*: The S/N-ratio should be so good that at an increased
volume one cannot make out any noise (free translation) ... I know
this is extremely vague to say the least.

* that's a contradiction in terms

If we are just obsessing on "how low can we go", I will leave
it to others as I confess to being an old-school pragmatist.


No, I am not. Although I didn't apply any compression if I did try to
compress my recordings I would get a huge noise problem. (Not that I
ever want to do it.)

For example, what
is the noise floor in your recording chain if you substitute a
load resistor for your home-made preamp? etc. etc.


Hm, can you please rephrase the question. :-)


The total noise floor in the system is made up of the
contributions from ALL the links in the chain. Many of
these can be isolated and measured independently in
order to identify the biggest problem (or the most easily
solved.) I was suggesting one experiment that would
get us closer to isolating the main contributor of the noise.


Uh, thank you. I't try to find a solution.

Thanks for all your input. It is very valuable for me.

Best wishes,
Igor



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Default What gain do you use with dynamic mics? was Argument against room noise?

On Oct 26, 12:01 am, "Igor (t4a)" wrote:
On 25 Okt., 17:10, wrote:





On Oct 25, 3:29 am, "Igor (t4a)" wrote:


On 25 Okt., 13:08, Mike Rivers wrote:


On Oct 25, 4:21 am, "Igor (t4a)" wrote:


Mike, I think you agree that noise is part of the physical reality.
Therefore you could go after signal/noise-ratio violations but not
after noise itself.


There's electrical noise, and then there's acoustic noise. Both
contribute to the signal-to-noise ratio of your final product. Both
can be addressed, but in different ways, and with different levels of
success. The microphone itself, since it's a transducer, contributes
to both the electrical and acoustic noise.


You can (and have) determine the electrical noise floor by measuring
what comes out of the preamp with no electrical signal going in.
Replacing the microphone with a 150 ohm resistor isn't to simulate
Browinian noise, it's (oversimplified explanation warning!) because
the input transistor has current noise and needs something across
which to develop a voltage that can be amplified. This is why there's
about a 3 dB difference between the preamp output noise with a 150 ohm
resistor at the input and with a short circuit at the input. If you
could put the microphone in a very soundproof enclosure and connect it
to the input, you'd see output noise close to that which you get with
the 150 ohm resistor. You might be able to get a little quieter than
this, but not much.


There are other sources of electrical noise other than "hiss." These
are things that you can fix. You can eliminate hum from the power
supply (try running your preamp on batteries). You can use balanced
wiring to minimize common mode hum and noise pickup in the cables. You
can put it in a well shielded box to keep stray RF out of the
innards.


As far as acoustic noise that the microphone picks up, the easiest way
to deal with that is to move to somewhere quiet. You can turn off all
noisemakers and isolate it from mechanical vibration.


But, as you surmised, it's not just about quiescent noise, the quality
of your final product is about signal-to-noise ratio. You can fix this
by putting more signal into the amplifier input. You can do this by
getting closer to the mic, or by using a more sensitive mic - one that
generates a higher voltage for the same sound level. If you don't like
how the mic sounds (and can't satisfactorily adjust it) then you need
a different mic. Try an omni. This will have negligible proximity
effect, but the tradeoff is that it will pick up more of the
refrigerator running in the kitchen or the truck driving by outside.
You just need to find the right compromise.


Alternately, you can just speak louder. More acoustic energy going
into the mic will result in more volts coming out, which will allow
you to reduce the preamp gain, which will reduce the electrical noise.
It will also bring the level of your voice at the microphone further
above the acoustic noise level at the mic, further improving the
signal-to-noise ratio.


So, you just have to do something. This won't get better on its own.


Thank you very much, Mike, I work on the problem, believe me.


After thinking some more I realized that I can even rephrase the
problem to the following question:


What gain setting do you use when you record someone with an RE-20 (or
some other dynamic mic).


Maybe the answer to this question can shed some light on the problem.
Do you actually run pre-amps at 60 dB gain and higher gains getting
signals with peaks at -9dB and less?


Thanks again.


Best wishes,
Igor- Hide quoted text -


- Show quoted text -


Yes. If you want I can send you a sample recording of voice using an
RE20 into a Sound Devices preamp built into the SD702 recorder. The
mp3 is approximately 387 KB.


bobs


Bob Smith
BS Studios
we organize chaoshttp://www.bsstudios.com-Zitierten Text ausblenden -


- Zitierten Text anzeigen -


First of all, thank you very much to everyone who cared to answer.

Secondly, despite all the details we discuss here, I must admit that
Bob blew away all my defenses I had erected in the past with the file
he provided. He recorded in his studio on his system using an RE-20 a
testfile at different distances between talent and microphone up to
one foot - and I have to say: wow!

The noise level is _decisively_ lower than my noise level at short
circuit. Now I have no the slightest doubt that the main problem
(apart from others) is the preamp.

Thank you very, very much Bob. This is the way to go.

Best wishes,
Igor- Hide quoted text -

- Show quoted text -


You may want to look at an RME Quadmic or Fireface 400 since you are
near the mfg. It has a pretty decent noise floor at 60 dB gain. Not as
quiet as the AEA TRP, though. RE20, SM7, MD441, MD431, MD421 (older
ver), M160, M130, M500, M260, R84, R92, M201, SM57 etc. are all really
good dynamic mics given a quiet, high gain, relatively neutral preamp.

bobs

Bob Smith
BS Studios
we organize chaos
http://www.bsstudios.com

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Richard Crowley Richard Crowley is offline
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Default Argument against room noise?

"Igor (t4a)" wrote ...
I would have even accepted this answer until I listened to Bob's file.
It is such a huge difference, he has roughly a 10 dB lower noise
floor. Although it is difficult to compare, the difference between his
signal to noise and mine is enormous.


I don't know if there is a similar saying in German, but
in the English-speaking world, we have the "80-20 rule".
The last 20% of what you are going for will end up
costing 80% of the total expenditure. In other words,
you have to start making hard decisions about whether
the cost/benefit ratio continues to be on the positive side.
http://en.wikipedia.org/wiki/Pareto_principle

If you were going into business doing commercially-
viable voice recording, then you should be worried about
your noise floor. But last time I checked, that wasn't your
goal. Have you changed your mind?

If we are just obsessing on "how low can we go", I will leave
it to others as I confess to being an old-school pragmatist.


No, I am not. Although I didn't apply any compression if I did try to
compress my recordings I would get a huge noise problem. (Not that I
ever want to do it.)


I would be tempted to use some gentle expansion (to reduce
the noise floor between syllables) as the final touch before
proclaiming it "done". :-)

The total noise floor in the system is made up of the
contributions from ALL the links in the chain. Many of
these can be isolated and measured independently in
order to identify the biggest problem (or the most easily
solved.) I was suggesting one experiment that would
get us closer to isolating the main contributor of the noise.


Uh, thank you. I't try to find a solution.


But it sounds like you already know that your preamp may
be the main contributor (both power mains hum and hiss
from the electronics/gain/components).


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Default Argument against room noise?

"Richard Crowley" wrote in message
...
I don't know if there is a similar saying in German, but
in the English-speaking world, we have the "80-20 rule".
The last 20% of what you are going for will end up
costing 80% of the total expenditure. In other words,
you have to start making hard decisions about whether
the cost/benefit ratio continues to be on the positive side.
http://en.wikipedia.org/wiki/Pareto_principle


That same principal is also applied the other way around: 20% of total
effort accouts for 80% of the end result. In the OP case, it sounds to me
as if he is investing a disproportionate amount of time on technical
excellence almost certainly at the cost of the time necessary to improve his
own performance. If the story he is reading is engaging, and if he tells
the story in a way that reaches people on an emotional level, no one... but
no one ... will notice underlying noise in the recording unless it is truly
excessive. With, of course, the one exception that he, himself, will hear
the noise ... and continue to obsess on it, thus continuing his distraction
from what is really important.

Steve King


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Default Argument against room noise?

On 27 Okt., 06:42, "Steve King"
wrote:
"Richard Crowley" wrote in message

...

I don't know if there is a similar saying in German, but
in the English-speaking world, we have the "80-20 rule".
The last 20% of what you are going for will end up
costing 80% of the total expenditure. In other words,
you have to start making hard decisions about whether
the cost/benefit ratio continues to be on the positive side.
http://en.wikipedia.org/wiki/Pareto_principle

That same principal is also applied the other way around: 20% of total
effort accouts for 80% of the end result. In the OP case, it sounds to me
as if he is investing a disproportionate amount of time on technical
excellence almost certainly at the cost of the time necessary to improve his
own performance.


From the viewpoint of an artist that is correct. From an engineer's

point of view, which is unfortunately mine, it is not. Why record the
same acoustic even at an inferior quality?

Actually, I would like to record at 8 .. 12 feet of distance but the
equipment I currently have does not allow it.

If the story he is reading is engaging, and if he tells
the story in a way that reaches people on an emotional level, no one... but
no one ... will notice underlying noise in the recording unless it is truly
excessive.


Agreed. However, I do not intend to compete with English natives (my
English readings are rather for my own practice and in case anyone
likes them I would be extremely honoured). Further, I know that good
talents simply sound nice. They are like a bunch of flowers (a bucket
as P. Routledge would depise to hear), no matter what they say. I am
not that kind of speaker, in fact I have to lower my tone permanently
otherwise the voice would sound bothersome rather quickly. So, do I
think I could ever go there? No, I don't. Do I know someone who enjoys
my (German) readings? Yes, I do. ;-)

With, of course, the one exception that he, himself, will hear
the noise ... and continue to obsess on it, thus continuing his distraction
from what is really important.


The point is as long as I am at war with my equipment it hard to
concentrate just on the reading.

Still, I am optimistic. The sound has improved, now there is only that
noise left ...

Thank you, Steve. I know what you're saying. Please don't worry.

Regards,
Igor

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Default Argument against room noise?

On 27 Okt., 02:02, "Richard Crowley" wrote:

I don't know if there is a similar saying in German, but
in the English-speaking world, we have the "80-20 rule".
The last 20% of what you are going for will end up
costing 80% of the total expenditure. In other words,
you have to start making hard decisions about whether
the cost/benefit ratio continues to be on the positive side.
http://en.wikipedia.org/wiki/Pareto_principle


I didn't know that there was a rule. But that perfection is like the
acceleration to the speed of light, is known ...

If you were going into business doing commercially-
viable voice recording, then you should be worried about
your noise floor. But last time I checked, that wasn't your
goal. Have you changed your mind?


No, I have not. But listening to voice recordings using earphones
somewhat elevates the quality level of what is necessary nowadays. And
of course, aren't we all want to create something that can last, at
least theoretically?

And certainly there is the pure technical question: How much is
missing to reach a certain level of proficiency. I would love to know.
Maybe, one day I will, maybe I will have to life with this unanswered
question for the rest of my life. Currently, I still want to know.

I would be tempted to use some gentle expansion (to reduce
the noise floor between syllables) as the final touch before
proclaiming it "done". :-)


See, others can compress their recordings. I should epxand. ;-)

Uh, thank you. I't try to find a solution.


But it sounds like you already know that your preamp may
be the main contributor (both power mains hum and hiss
from the electronics/gain/components).


Frankly, I am heavily confused. I have seen calculations that say that
thermal noise of a 150-Ohm-resistor at 20C lead to -131dB noise which
when noiselessly amplified by 60 dB end in a noise floor of -71 dB
(-74 dB in "my scaling"). If Bob can easily beat those figures than I
am somewhat puzzled but I have to accept that calculating is one part,
doing it quite another.

There is always hope. The next step will lead into another direction
(another pre-amp must wait). I hope my questions don't bother you and
the others too much.

Best wishes,
Igor



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Default Argument against room noise?

"Igor (t4a)" wrote...
I didn't know that there was a rule. But that perfection is like the
acceleration to the speed of light, is known ...


But it is the last few %% that costs most of the money.

There is always hope. The next step will lead into another direction
(another pre-amp must wait). I hope my questions don't bother you and
the others too much.


We all learn from the discussion. I just feel a bit guilty about
enabling your obsession for low noise at the expense of the
"real" objective of recording some stories, etc. :-)
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Default Argument against room noise?

"Igor (t4a)" wrote ...
Actually, I would like to record at 8 .. 12 feet of distance
but the equipment I currently have does not allow it.


Why? The only people that record at that distance are wrestlers.
It is impractical for any other situation.
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Laurence Payne Laurence Payne is offline
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On Sat, 27 Oct 2007 04:22:46 -0700, "Richard Crowley"
wrote:

Actually, I would like to record at 8 .. 12 feet of distance
but the equipment I currently have does not allow it.


Why? The only people that record at that distance are wrestlers.
It is impractical for any other situation.


It's standard practice for operatic voices.
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Richard Crowley Richard Crowley is offline
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"Laurence Payne" wrote ...
"Richard Crowley" wrote:
Actually, I would like to record at 8 .. 12 feet of distance
but the equipment I currently have does not allow it.


Why? The only people that record at that distance are wrestlers.
It is impractical for any other situation.


It's standard practice for operatic voices.


Last time I checked, the OP was recording speech,
not music.
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Laurence Payne Laurence Payne is offline
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On Sat, 27 Oct 2007 09:32:16 -0700, "Richard Crowley"
wrote:

Actually, I would like to record at 8 .. 12 feet of distance
but the equipment I currently have does not allow it.

Why? The only people that record at that distance are wrestlers.
It is impractical for any other situation.


It's standard practice for operatic voices.


Last time I checked, the OP was recording speech,
not music.


If you can cite wrestlers, I can cite opera singers :-)


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Igor (t4a) Igor (t4a) is offline
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On 27 Okt., 13:18, "Richard Crowley" wrote:
"Igor (t4a)" wrote...
...

We all learn from the discussion. I just feel a bit guilty about
enabling your obsession for low noise at the expense of the
"real" objective of recording some stories, etc. :-)


There is no need for it. The "obsession" has developed on its own. I
think once you start playing your own recordings and professional work
on the same system you get this desire to bring your pieces to a
similar quality level.

If there was a "trap" in this history of striving for low noise than
it is the current conception of distant recording. As long as my lips
virtually touched the grille I've never had a (background) noise
problem. But that was the point in this development were it was said
that if the initial recordings sound terrible there is not much that
can be done to fix them (-"soundprocessing for narration"). Moreover,
there are mouth noises which are extremely difficult to control. So, I
moved away from the microphone farther, farther until it sounded
right. That "magical" distance is according to my experience between
8 .. 10 inches. At that distance and with my somehow soft voice I had
a noise problem.

So? Get the RE-20 and you can get closer again without getting that
bass lift. Hm, but somehow I still get that bass lift even with the
RE-20. Well, it is not as terrible as with the Shure Beta but it
sounds boomy still. (Look at the heavy bass cut Don suggested - which
was great btw, thank you.) The latest recording was taken at a
distance of 6 inches and although the noise maybe regarded as bearable
for an amateur recording I nevertheless wonder, if there is a way out
of this dilemma.

As you may have noticed I am having great fun in this process. So,
don't worry. I like recording, I like microphones, I like 24 bit
recordings, I like cutting. It probably takes too much time away from
me at the time, but I'll cut back on it a tad soon.

Thanks again for your professional input.


Best wishes,
Igor

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Skler Skler is offline
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First of all, theoretically in a total quiet room with no air in it,
e.g. in space, the Sure Beta should create more noise (at a
temperature above 0 Kelvin).



Have you considered a liquid helium cooling arrangement for the magnet and
the pole pieces?

A Beta would probably be better off if you tossed it into the mouth of a
volcano.


Skler



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Igor (t4a) Igor (t4a) is offline
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I wasn't fully aware of that dynamic microphones are not excactly a
perfect match for the recording situation I've had in mind.

So, what part do you play in my realization process. None so far,
unfortunately.

Try harder.

On 30 Okt., 05:13, "Skler" wrote:
First of all, theoretically in a total quiet room with no air in it,
e.g. in space, the Sure Beta should create more noise (at a
temperature above 0 Kelvin).


Have you considered a liquid helium cooling arrangement for the magnet and
the pole pieces?

A Beta would probably be better off if you tossed it into the mouth of a
volcano.


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