Topic: Microphone Input-Noise Comparison at max. gain setting

[Arni99]

Here an updated list of popular recorder´s mic-in noise:
http://www.avisoft.com/recordertests.htm

[sanaka]

+T

That's cool info. Hope they add the R44 at some point.

Peace

[Carlos E. Martinez]

That's cool info. Hope they add the R44 at some point.

Yes, I'd like to see the info on the R4Pro and the R44 there, but my guess puts it probably close to the the R-09HR or the Olympus. Still a long way from the Sound Devices, Tascam or Fostex.

[Arni99]

Now you know why I love my Sony MZ-RH1 that much .

[Mr.Fantasy]

Now are the recorders listed from highest quality to lowest quality?

I am ignorant about these statistics that they are measuring.....which of these measurements are most important?

I am guessing they ARE ranked in order of quality? Or if not quality, what are they ranked by?

[Carlos E. Martinez]

Now are the recorders listed from highest quality to lowest quality?

I am ignorant about these statistics that they are measuring.....which of these measurements are most important?

I am guessing they ARE ranked in order of quality? Or if not quality, what are they ranked by?

They are ranked by best EIN, where the highest the equivalent input noise the better.

Though in the lower cases you will find units which are not CF based and also a mic preamp.

[flintstone]

Raimund Specht's tests provide two sets of information.  First, they show the equivalent input noise (EIN) of the preamps, which is the sound pressure level that is the same as the noise of the electronics.  Any sound quieter than this will be lost in the noise of the preamp.

Second, they show the sound pressure level where the preamp clips.  Any sound louder than this won't be captured accurately by the recorder.

The difference between the EIN and the clipping point is the dynamic range of the recorder.  Generally speaking, a larger dynamic range is preferable.

The results show on the Avisoft web site are not in any sorted order.  The three recorders at the top of the chart (Sound Devices 722, Tascam HD-P2, Fostex FR-2LE) have the best test results, but the fourth-best recorder (IMO, Sony PCM-D50)
is at the bottom of the chart.

The results posted by Dr. Specht match the reports from the field posted in this forum and others.  For example, the R-09HR has a quieter preamp than the R-09.  The Microtrack II does not perform as well as the Microtrack 2496.  The Microtrack 2496 1/8-inch input has a clipping threshold that's higher than many other small recorders.  The Korg MR-1000 preamp is good but not great.  The Olympus LS-10 performs better at full gain on low mic sensitivity than high sens.

Dr. Specht's tests are controversial among tapers because they show the equivalent input noise with the preamp pushed to maximum.  That may be a likely scenario when recording specific nature sounds, but it's unlikely for music recording or recording ambient sounds.  Unfortunately, you can't assume that the results with preamp gain at maximum will be the same as with preamp gain half-way up.

Also, the EIN performance of a recorder doesn't come into play when you're recording a loud source, like an amplified music concert.  If the musicians all wear earplugs, chances are you don't need to worry about Dr. Specht's EIN numbers.  You should pay attention to the input clipping numbers, because these can give you an idea how often you'll need to attenuate the mic input.  This reveals one weakness of the Hi-MD minidisc machine:  A preamp that is susceptible to clipping at a lower sound pressure level than most other hand-held recorders.

It's important to remember that the EIN test results don't tell the whole story.  For example, the Olympus LS-10 looks good on the Avisoft tests.  But, thanks to tests done by Guysonic, we know that the LS-10 filters sounds below 200 Hz pretty severely.  It's like a low cut filter you can't turn off.  This helps reduce handling noise and the sounds of the wind (both big problems for a hand-held recorder), but you may not like the results for music recording.

Flintstone

[Arni99]

Well said flintstone.
Yes the HI-MD recorders mic-in preamps tend to clip when used with non-attenuated high-sens-mics at loud amplified concerts.
You need lots of experience with your gear to know, whether the mic-in can stand the SPL of a concert or not.
I´ll try the RH1-mic in at a rock-concert with high-sens sp-cmc-8 cardiodis AND a -20dB attenuator cable connected in combination with a battery box.
At the same time I´ll use my R-09HR with my SP-preamp and my DPA 4061 on line-in.

[illconditioned]

Raimund Specht's tests provide two sets of information.  First, they show the equivalent input noise (EIN) of the preamps, which is the sound pressure level that is the same as the noise of the electronics.  Any sound quieter than this will be lost in the noise of the preamp.

Second, they show the sound pressure level where the preamp clips.  Any sound louder than this won't be captured accurately by the recorder.

The difference between the EIN and the clipping point is the dynamic range of the recorder.  Generally speaking, a larger dynamic range is preferable.

The results show on the Avisoft web site are not in any sorted order.  The three recorders at the top of the chart (Sound Devices 722, Tascam HD-P2, Fostex FR-2LE) have the best test results, but the fourth-best recorder (IMO, Sony PCM-D50)
is at the bottom of the chart.

The results posted by Dr. Specht match the reports from the field posted in this forum and others.  For example, the R-09HR has a quieter preamp than the R-09.  The Microtrack II does not perform as well as the Microtrack 2496.  The Microtrack 2496 1/8-inch input has a clipping threshold that's higher than many other small recorders.  The Korg MR-1000 preamp is good but not great.  The Olympus LS-10 performs better at full gain on low mic sensitivity than high sens.

Dr. Specht's tests are controversial among tapers because they show the equivalent input noise with the preamp pushed to maximum.  That may be a likely scenario when recording specific nature sounds, but it's unlikely for music recording or recording ambient sounds.  Unfortunately, you can't assume that the results with preamp gain at maximum will be the same as with preamp gain half-way up.

Also, the EIN performance of a recorder doesn't come into play when you're recording a loud source, like an amplified music concert.  If the musicians all wear earplugs, chances are you don't need to worry about Dr. Specht's EIN numbers.  You should pay attention to the input clipping numbers, because these can give you an idea how often you'll need to attenuate the mic input.  This reveals one weakness of the Hi-MD minidisc machine:  A preamp that is susceptible to clipping at a lower sound pressure level than most other hand-held recorders.

It's important to remember that the EIN test results don't tell the whole story.  For example, the Olympus LS-10 looks good on the Avisoft tests.  But, thanks to tests done by Guysonic, we know that the LS-10 filters sounds below 200 Hz pretty severely.  It's like a low cut filter you can't turn off.  This helps reduce handling noise and the sounds of the wind (both big problems for a hand-held recorder), but you may not like the results for music recording.

Flintstone

Note: what that website shows is the 0dB input level for the *most senstive* setting of the preamp.  This is useful since it tells you how *low* the mic level input can be (to get full scale, ie., use all the "bits" of the recorder).  These numbers, combined with your microphone sensitivity, will tell you what the self noise (dBA) of your setup will be, and whether it is limited by the mics or the recorder.  This is what the nature recording folks need to know.

There is another set of measurements, from Guysonic, that show the maximum input level for the *lowest sensitivity* setting of the preamp.  Those are the numbers we tapirs should be watching to prevent overload "brick wall" distortion.

  Richard

[DSatz]

It's not very useful to measure the input noise of an open input. In real life you connect some relatively low source impedance across it, and that changes the noise picture enormously.

There is also very little sense in comparing the noise levels of different recorders with "wide open" record level settings, since that setting corresponds to such wildly different sensitivities in the different recorders. That is like comparing apples, oranges, lemons and persimmons.

What's needed instead is a set of results with some well-chosen sensitivity values, which are then kept the same among all the recorders.

In other words (assuming that we're testing microphone inputs here), pick a voltage that's typical of what modern condenser microphones put out when you're recording sound at some level such as 100 dB SPL. Set the gain controls on each recorder so that 0 dBFS (digital full scale) is reached but not exceeded at that level. Then turn off the test signal (leaving the low driving impedance of the generator across the input) and measure the residual noise.

THAT would begin to tell you something about which recorders' inputs are noisier than which other ones under something like typical recording conditions.

--best regards

[Arni99]

Yes, but nevertheless the figures tell the truth for at least MY 3 recorders:
Sony MZ-RH1 HI-MD better than
Edirol R-09HR better than
Edirol R-09 (sold yet)

Thats exactly what I learned in many many concert and/or speech recordings. I was kind of shocked when I heard the noise of the R-09 after heavy use of my MZ-RH1.

The R09-HR is considerably better than the R-09 as guysonic already statet in his tests.

[JM Charcot]

Yes, but nevertheless the figures tell the truth for at least MY 3 recorders:
Sony MZ-RH1 HI-MD better than
Edirol R-09HR better than
Edirol R-09 (sold yet)

Thats exactly what I learned in many many concert and/or speech recordings. I was kind of shocked when I heard the noise of the R-09 after heavy use of my MZ-RH1.

The R09-HR is considerably better than the R-09 as guysonic already statet in his tests.

Hello Arni,

do you consider the R09HR to be now close to the RH1 or is there still a way to go?
I'd like to use it for ambient (not loud) recordings.. don't know if it can be a good replacement to my Hi-MD..

Kind regards,

JM.

[Arni99]

Yes, but nevertheless the figures tell the truth for at least MY 3 recorders:
Sony MZ-RH1 HI-MD better than
Edirol R-09HR better than
Edirol R-09 (sold yet)

Thats exactly what I learned in many many concert and/or speech recordings. I was kind of shocked when I heard the noise of the R-09 after heavy use of my MZ-RH1.

The R09-HR is considerably better than the R-09 as guysonic already statet in his tests.

Hello Arni,

do you consider the R09HR to be now close to the RH1 or is there still a way to go?
I'd like to use it for ambient (not loud) recordings.. don't know if it can be a good replacement to my Hi-MD..

Kind regards,

JM.

just recorded some samples for you:
sample 1: RH1_external mic_high_sens_setting_gain 20 (66% of max. gain)
http://www.file-upload.net/download-1048181/RH1_external-mic_high_Sens_setting_gain-20.wav.html

sample 2: R09_internals_gain 53_high_sens_setting (66% of max. gain)
http://www.file-upload.net/download-1048185/R09_internals_gain-53_high_sens_setting.WAV.html
(it´s a train passing by at the beginning of the file)

sample 3: R09_external mic_gain 53_high_sens setting (66% of max. gain)
http://www.file-upload.net/download-1048190/R09_external-mic_gain-53_high_sens-setting.WAV.html

All 3 files recorded from my balcony, normalized with Sound Studio 3.5.

R09HR files recorded at 24bit/44.1kHz
RH1 file recorded in HI-SP(256kbit/Atrac3+) and converted to WAV with "HI-MD Transfer" on my iMac.
External mic used for this test was the SP-CMC-8 cardioid mic.
Plugin-Power used for all 3 files.

[JM Charcot]

Yes, but nevertheless the figures tell the truth for at least MY 3 recorders:
Sony MZ-RH1 HI-MD better than
Edirol R-09HR better than
Edirol R-09 (sold yet)

Thats exactly what I learned in many many concert and/or speech recordings. I was kind of shocked when I heard the noise of the R-09 after heavy use of my MZ-RH1.

The R09-HR is considerably better than the R-09 as guysonic already statet in his tests.

Hello Arni,

do you consider the R09HR to be now close to the RH1 or is there still a way to go?
I'd like to use it for ambient (not loud) recordings.. don't know if it can be a good replacement to my Hi-MD..

Kind regards,

JM.

just recorded some samples for you:
sample 1: RH1_external mic_high_Sens_setting_gain 20 (66% of max. gain)
http://www.file-upload.net/download-1048181/RH1_external-mic_high_Sens_setting_gain-20.wav.html

sample 2: R09_internals_gain 53_high_sens_setting (66% of max. gain)
http://www.file-upload.net/download-1048185/R09_internals_gain-53_high_sens_setting.WAV.html
(it´s a train passing by at the beginning of the file)

sample 3: R09_external mic_gain 53_high_sens setting (66% of max. gain)
http://www.file-upload.net/download-1048190/R09_external-mic_gain-53_high_sens-setting.WAV.html

All 3 files recorded from my balcony, normalized with Sound Studio 3.5.

R09HR files recorded at 24bit/44.1kHz
RH1 file recorded in HI-SP(256kbit/Atrac3+) and converted to WAV with "HI-MD Transfer" on my iMac.
External mic used for this test was the SP-CMC-8 cardioid mic.
Plugin-Power used for all 3 files.

Thanks! 

It looks like the RH1 is the winner..
Which microphone did you use?

Kind regards,

JM.

[Arni99]

SP-CMC-8(AT943) as stated above .

[JM Charcot]

Ooops sorry didn't read it... 

[DSatz]

Arni99, even a stopped clock is right twice a day (unless it's a 24-hour clock)--and as we saw in the Edwards case last week, sometimes even the National Enquirer gets a story right.

All I'm saying is that the method as described isn't valid. That doesn't mean that every single finding will be wrong in a predictably patterned way; there isn't a systematic bias. It only means that many if not most of the results will probably be wrong more or less at random. Unfortunately you can't tell in advance which cases those will be, or which direction they'll be wrong in, or by how much. The individual data points are presumably real, but they've been collected in a way that makes them garbage as a set.

I've spent a fair amount of time trying to make reliable measurements of professional and semi-professional mike preamps. It's not easy! Interpreting and comparing the results isn't simple, either.

I believe in the slogan "Make things as simple as possible, but no simpler." Noise measurements are a very good example of a subject that shouldn't be made simpler than it actually is.

--best regards

[Arni99]

Arni99, even a stopped clock is right twice a day (unless it's a 24-hour clock)--and as we saw in the Edwards case last week, sometimes even the National Enquirer gets a story right.

All I'm saying is that the method as described isn't valid. That doesn't mean that every single finding will be wrong in a predictably patterned way; there isn't a systematic bias. It only means that many if not most of the results will probably be wrong more or less at random. Unfortunately you can't tell in advance which cases those will be, or which direction they'll be wrong in, or by how much. The individual data points are presumably real, but they've been collected in a way that makes them garbage as a set.

I've spent a fair amount of time trying to make reliable measurements of professional and semi-professional mike preamps. It's not easy! Interpreting and comparing the results isn't simple, either.

I believe in the slogan "Make things as simple as possible, but no simpler." Noise measurements are a very good example of a subject that shouldn't be made simpler than it actually is.

--best regards

Your own ears are the best instrument for "measuring" , in my case it´s not hard to tell the RH1 has the best internal preamp for silent sources.
Its up to the professionals to do real, objective measurements. I don´t have the knowledge, but I got ears that tell me which recorder to use for which recording situation and in the end that´s what it´s all about after 21 years of taping.
 

[digifish_music]

Arni99, even a stopped clock is right twice a day (unless it's a 24-hour clock)--and as we saw in the Edwards case last week, sometimes even the National Enquirer gets a story right.

I've spent a fair amount of time trying to make reliable measurements of professional and semi-professional mike preamps. It's not easy! Interpreting and comparing the results isn't simple, either.

I believe in the slogan "Make things as simple as possible, but no simpler." Noise measurements are a very good example of a subject that shouldn't be made simpler than it actually is.

--best regards

For subjective listening tests, I have found the biggest issue with comparisons are:

1. Finding a constant noise source that is interesting to listen to and spans the frequency spectrum in ways that your intended audience would use the preamp (i.e valid source).
2. Level matching.

If you are testing preamps, then multi-track recorders are your friend since parallel recording will allow you to make direct comparisons of the same source material (see my crude attempt at this here, last recording on the initial post).

If you are testing recorders, then you really need to record the same source under controlled conditions (IMO). Although how necessary this is depends on how close the recorders are, the R44 vs R09HR internal mic comparison for example is blindingly obvious.

But it means to do it correctly you need 2 sets of identical stereo micsa and there are now 4 permutations of mic and preamp to use: Pre1 + Mic-set A vs Pre 2 + Mic-set A vs Pre 2 + Mic-set B vs Pre 2 + Mic-set B.

From my reading of the auditory psychoacoustic literature one of the most sensitive listening conditions is relatively fast A/B switching with less than 7 second samples of material and no gaps or loud noises at the junctions. I used 2 in my example, but 3 probably is better since it takes a while to focus your attention on particular details.

digifish

[Ozpeter]

Seems to me there are two issues here - first, people want the best regardless of actual requirement, so the interest in making these comparisons is understandable.  However, the real issue is "what problems can you hear with your equipment in actual normal use?"  - and I strongly suspect that these days, when recording live music, preamp noise is unlikely to be an issue other than with really cheap and nasty equipment.

I record classical music.  When I look at the meters between movements, with levels set so that the loudest parts of the performance will peak to close to 0dB, typically they are flickering around -55dB at best.  If I bury the mic under a pile of blankets in a quiet room at night, I might see the meters hover around -85dB.  In other words, the ambient noise of a performance space is normally way above the noise floor of the equipment.

So, avoid the few preamps that might be identified by measurement or reputation as significantly worse than the rest, and you'll probably be perfectly happy with the performance of the rest under real world music recording conditions.

Or am I being unrealistically complacent?