Audio Technica AT897 with small consumer grade low end DVR
 

I want to record the speech in acoustically live environment. Speaker will be within 8" from Mic. I will record it in a Hall, which isn't acoustically engineered, it has many ceiling fans, several pillar, and a net of Speaker for sound reinforcement. Because cardioid mic has low off axis rejection, therefore I will use the shotgun or line-cardioid to reject the all unwanted noise of fans etc.

Do you think shotgun won't help me? I saw many videos no YouTube in which cardioid or Omni mic picking up so much ambient noise. There is a complete PA system, but I want to recorder through my own chain, i.e. Audio Technica AT897 -->??? -> Sony Digital Voice Recorder ICD-UX200.

I'll sync it with still photos. Hence sync won't bother me, it is like a slide show with a voice track.
I will patch XLR Mono Balanced to TRS Stereo unbalanced 1/8” like this:

XLR Pin 1 to unconnected
XLR pin 2 to Mini Jack tip and ring
XLR pin 3 to mini-jack sleeve

I'm a newbie; therefore I asked so many questions, any advice from you guys is very worthwhile for me, Sorry for my bad English.

1) How do I know if my DVR has plug-in power DC voltage? If DC blocking is inevitable, then what value of volt should I use for the capacitor? As well as the link below suggesting me that I can use this same capacitor to roll off low frequencies and it depends upon the value of µf which should lies b/w (1 to 5). I want to roll off sound frequency below 80Hz then what value of µf should I use for the capacitor. However my DVR has Low cut filter and Noise-Cut function also my mic has integral 80 Hz high-pass filter, then do I really need this capacitor rolling off?

Camcorder Mic Adapters


2) My DVR doesn’t have manual recording gain control; it has only three sensitivity setting: S-High, High, and Low and it has minimum input level of 0.9 mV and AT897 has Nominal open circuit output voltage of 8.9 mV (battery) at 1 V, 1 Pascal, then Do I need an attenuator?

ICD-UX200: Recorder Microphone jack input for plug in power has minimum input:
level 0.9 mV, 3 kilohms or lower impedance microphone.

AT897:
Element Fixed-charge back plate, permanently polarized condenser
Polar pattern Line + gradient
Open circuit sensitivity Battery: –41 dB (8.9 mV) re 1V at 1 Pa
Impedance Battery: 300 ohms
Maximum input sound level Battery: 115 dB SPL, 1 kHz at 1% T.H.D.
Dynamic range (typical) Battery: 98 dB, 1 kHz at Max SPL
Battery type 1.5V AA/UM3
Battery current / life 0.4 mA / 1200 hours typical (alkaline)
Output connector Integral 3-pin XLRM-type

Spec. Sheets:
http://www.docs.sony.com/release/ICDPX820.pdf
http://www.docs.sony.com/release/ICDUX200.pdf
http://www.audio-technica.com/cms/re...897_submit.pdf

The voltage rating of the blocking capacitor is not important, anything around 10 volts or so should be fine.

How do you know if your DVR has plug-in power on the mic input? It says it does right in the specs you quoted. "ICD-UX200: Recorder Microphone jack input for plug in power ..."

1 Pascal is an indication of sound pressure and a 1 Pascal sound is very loud, approximately 94dB SPL. In contrast, normal day-to-day conversation is about 60dB SPL while a jack hammer @ 1 metre is about 100dB SPL. How much voltage your mic will actually be putting out depends on how loudly the person speaking is projecting their voice. Your DVR specs on the other hand are calling for a minimum input voltage and they don't say how much over that it can go without distorting or clipping. So at this point there is insufficient information to say whether you'll need an attenuator or not. The only thing you can do is try it (before the day you need to record the real speech) and see what happens.

Don't expect the shotgun to completely eliminate the noise from the ceiling fans, etc. Shotguns have LOWER sensitivity to sounds off-axis than to sounds on-axis but it is a relative thing. They still pickup SOME sound from all directions, just they pickup LESS from directions other than where they're pointed. And that directionality is frequency dependent ... pretty pronounced in the range of voice frequencies but tending to get almost omni in response at lower frequencies (such as the whump whump whump of fans, for instance). And when the reflections of the speaker's voice coming off the walls and pillars, not to mention the PA, hits the shotgun, they'll interact with the direct sound and it will probably sound like the speaker is talking in a cave.

Thank you for all, AT897 is working in ICD-UX200.I patched XLR Mono Balanced to TRS Stereo unbalanced 1/8” like this:
XLR Pin 1 to unconnected
XLR pin 2 to Mini Jack tip and ring
XLR pin 3 to mini-jack sleeve.
• I used 4.7 µf non-polar 50V capacitor between XLR pin 2 and mini jack tip/ring
• I didn’t match their impedances (AT896 = 300Ω and UX200 = <3000Ω). Guys me that told impedance was Ok.
• I didn’t use any attenuator or preamp.
• Recorder’s Low Cut filter is on
• I record it at “ST” High-quality stereo recording mode (44.1 kHz/192 kbps)
• Recorder was set to “High” sensitivity however “high” is undesirably High and low is too much low, as you have told me before
• Microphone 80Hz filter is on
• Mic is almost ½ feet away from me
• I record it in Room (12’x10’x10’) with Furniture

My problem is that why it is creating hiss. How I get rid of hiss from recoding?:
• Is it capacitor problem (i.e. 4.7 µf non-polar 50V)
• Is it impedance mismatch

Or if there is nothing wrong in above two things then which is best software to denoise this type of hiss:
• iZotope RX
• Wave lab 7 or something else

I’m complete novice. I mistakenly download Cubase 5 but it doesn’t have any denoiser.

Please check my hiss test:
YouTube - AT897 Hiss Problem with Sony ICD-UX200

"XLR Pin 1 to unconnected' ???

1. XLR Pin 1 should be connected to the 'shield' of a short good quality shielded mic cable, at the other end, connect the cable's 'Shield' to the 3.5mm mini-plug's sleeve/ground.
2. Hiss can be attenuated by using a Low-pass/ High-cut EQ filter, starting at around 10kHz. t
3. The cheap version of "Sound Soap" can attenuate the hiss further.
4. Use the money saved on expensive NR app.s to purchase an audio recorder and/or camera with XLR inputs and manual gain control.

1. Fact
2. Fact
3. Fact
4. Opinion

(Do not confuse "Attenuate" with 'Remove'.

1. No, not necessary b/c have isolated system just DVR, Mic and just 3 meter unshielded cable i.e. NO RFI interference. As well as someone told me that If connect XLR 1 to sheild with this type of mono to stereo connection then I should not use this in Phantom power, otherwise something will go wrong. Am I right?

2. I'm sorry I novice, didn't understand, I already enabaled recorder's Low-cut filter and mic's 80 Hz filter. Are you telling me that I use "Low-pass/ High-cut EQ filter" in software mode? I'm downloading iZoptop RX, is this software has "Low-pass/ High-cut EQ filter"?

4. I have already purchased these things.

The shield should always be connected at both ends for microphone cables.

"Phantom Power" can only be used or available in recording devises having the XLR / balanced input configuration. "Plug-in power' is a low voltage 'bias current' and eliminates the need of battery power. (on some mics). Since your obviously using the mics internal battery power, that's why you need the blocking capacitor to negate the low voltage bias current. (aka, Plug-in power©. (which is a copyrighted term. (Sony I think), as is the term "Phantom Power" invented by Neumann.

The 3.5mm mini-plug's tip and ring are tied together to feed both L&R channels the same signal.

And yes, XLR's pin-1 and pin-3 are normally tied together for unbalanced operation, though in some instances, pin-3 is not connected. I would check the mic's manual to be sure for unbalanced operation.

Microphones and recorders rarely have a high-cut filters.

XLR Pin 1 to unconnected
XLR pin 2 to Mini Jack tip and ring
XLR pin 3 to mini-jack sleeve.
• I used 4.7 µf non-polar 50V capacitor between XLR pin 2 and mini jack tip/ring

Tip isn't connected to sleeve or ground or shield, you mixed connections completely. Please visit:

Camcorder Mic Adapters

You didn't elaborate on "Low-pass/ High-cut EQ filter".

Your're right, the blocking cap. is in series on pin -2 or tip.
"Tip isn't connected to sleeve or ground" It shouldn't be, that would short out the signal all together.

Please clarify what you mean by "XLR Pin 1 to unconnected"
As I stated, this must be connected the cable shield

"You didn't elaborate on "Low-pass / High-cut EQ filter" Different terms, also known as, but do the same thing.
"High-cut" filter, also known as, "Low-pass filter": Attenuates high frequencies, (Hiss for instance) Low frequencies pass though unaffected.
"Low-cut filter", also known as "High-pass filter: Attenuates low frequencies. ( Rumble for instance) High frequencies pass though unaffected.
EQ= Frequency Equalization
Hope this helps.

If I connect XLR 2(in-Phase) to ground/Sleeve and XLR 3(out-of-Phase) also connected to ground/sleeve then XLR 2 and XLR 3 will cancel out each other due to phase difference!

b/c I have isolated system just DVR, Mic and just 3 meter(I think it is too short to get RFI) unshielded cable i.e. NO RFI. Hence I left XLR 1 unconnected, it wasn't connect to shield. However I was advised as "the shield is connected to pin 1 at the XLR end but left floating, not connected to anything, at the TRS end."

Do you think I can make "Low-Pass Filter" using same voltage blocking Capacitor? as it is advised in
Camcorder Mic Adapters and
Opamp Labs Inc <> RFC Calculator <> www.opamplabs.com

But couldn't understand what is the meaning of "you want frequency response down to 20 Hz, then you would use a 3.18 microfarad capacitor" in above mentioned link

What is the meaning to "down to 20 Hz", is it means below 20Hz (19, 18, 17, ....) OR till 20 Hz (....,22,21,20)? I'm sorry English isn't my native language.

XLR pin 1 should be connected to cable shield, true. This extends the mic's case shield all the way to the recorder. But the cable shield can be left 'floating' at the TS/TRS end, connecting the conductor from XLR pin 3 to TRS sleeve/ground and leaving the shield unconnected. See these "Rane Notes" technical papers on balanced to unbalanced connections and the "pin 1 issue."

Sound System Interconnection cable diagram # 5 or 6.
Pin 1 Revisited
Grounding and Shielding Audio Devices

Connecting the cable shield to audio signal ground at the recorder end sends any hum or interference hitting the cable directly into the audio circuits. The recorder's plastic case is not a shield and the TRS sleeve is going to audio ground, not a case shield. If the recorder case was a shielding enclosure and the input was balanced it might be a different story.

I am the author of the page you are asking about. What I meant was that assuming a 2500 ohm input impedance (which you don't really know without measuring it), using a 3.18uF capacitor will give you a 3dB rolloff at 20Hz. That means that the low-frequency response will curve down and the response will be 3dB down at 20Hz.

For example, this diagram shows the 3dB down point at around 42 Hz...
http://www.ajdesigner.com/images/spe...quency_bak.png

Ok Thank you.

1) If I want to roll off ≤80Hz (audio frequency) to 3dB then I should use 0.7uf capacitor a/c to your formula?

2) But If I want to roll off high frequency (Hiss) then is this formula applicable?

3) what is the value of Hiss in Hz in this audio:

http://www.youtube.com/watch?v=SGpvyZCxPzc

Yes, ASSUMING that you have a 2500 ohm input impedance.
REPEATING: YOU DON'T KNOW WHAT YOUR INPUT IMPEDANCE IS, SO THIS FORMULA IS OF LIMITED USEFULNESS.

NO
1) This DC blocking capacitor, along with the (UNKNOWN) input impedance forms a HIGH-PASS FILTER. It is good for rolling off LOW frequencies, but NOT high frequencies.
2) You cannot filter hiss even with a high-cut (low-pass) filter because hiss is broad-band. If you remove all the hiss frequencies, then you remove all the audio, too.

Hiss is BROAD-BAND. You cannot remove hiss with a simple filter.

I can't hear any significant hiss in this audio. I hear a lot of ambient noise, but no hiss.

No, I'm assuming it is 3000 ohm from Manual:
"ICD-UX200: Recorder Microphone jack input for plug in power has minimum input:
level 0.9 mV, 3 kilohms or lower impedance microphone."

I analyze it by iZotop RX Advance, It has two types noise one at 462Hz, other is boardband hiss >10000Hz. If use hum removal tool, set base frequency at 462Hz, filter Q at 163.72 and harmonic gain at -80dB then it tooooon is completely disappear. And the Hiss is disappear if I enable Low pass filter, Low-Pass freq. is 11437.2Hz, filter Q is 0.20 and Harmonic gain is 0.3 dB, however it slightly effect on my voice.

That's not the input impedance. That's the maximum impedance of the microphone that it's designed to have plugged into it. Read that specification as saying "You can use any microphone that has a 3000 ohm impedance or lower."

It is clip which isn’t in English recorded on my set up:

YouTube - High Sensitivity LFC No 80Hz.wmv

Then I clean it through iZotope RX Adance and made its Video through image in “.rm” format by Sony Vegas Pro 10:

YouTube - High Sensitivity LFC No 80Hz 2x Denosing 17.08 Gain

Now my last question is that can split microphone output wire into “Y” formation, one to supply input to PA system other to my mini Sony DVR. Is it possible without getting any serious problem or will there be any compromise in quality or gain etc.?

Passively splitting a mic to two inputs with a simple "Y" cable is not a good idea. It changes the loading on the mic and puts the two device inputs in parallel with each other. There's no predicting what the effect will be but it's rarely good - the mic's tone changes and you run a big risk of introducing ground loops, hum ,etc. You can get a true transformer-based mic splitter for very little expense and that's the right way to go, isolating the two devices from one another. See SP1X2 AND SP1X3 MIC SPLITTERS - Catalog - Whirlwind and http://www.bhphotovideo.com/c/product/351512-REG/Whirlwind_SP1X2_SP1X2_1x2_Mic.html

If the shotgun mic is still 8 feet from the subject as in your original post, you will not be successful in feeding this to a PA system that covers the mic's location. It will only cause feedback with no actual reinforcement of the subject. You could feed it to a remotely located PA system with loudspeakers that are far removed from the mic's location, but I don't think that was your intention.
The difference in signal levels between getting a good recording and sending the exact necessary level to a PA that covers the mic's location is also dramatically different and often very touchy, even with a good vocal mic fairly close to the subject.
A splitter, while much better than a Y cable, still won't give you any additional gain boosting of the mic or differential control of the two output signals.
I suggest a small mixer to gain better control of the two signal paths, and even then you can't use a shotgun mic 8 feet from the subject for a PA system that covers the mic's location, it simply won't work.

What is the meaning of passively splitting?

I can purchase small samson mixer, I'll let you know the shortly the model #, Do you think mix can sloving my splitting problem?

Syed, I am a bit surprised to see you posting here. Most of the questions you are asking here, you have already asked on another forum, and they have been answered there.

Two of us in the other forum suggested you try a small mixer. That will be a good way to split the signal from your mic, and feed it to the PA system and also to your recorder. As I mentioned in the other forum, your recorder does not have a line level input (only a mic level input), nor does it have a recording level meter or a full-range recording level control. So even if you use a mixer, you will need an attenuator to lower the signal level from the mixer going to the recorder. And you will need to determine the size of that attenuator experimentally, since the Sony recorder has no meter. It would be easy, but time consuming, for someone knowledgeable to do that; for a novice like you it may be rather difficult. IMHO, that Sony recorder is your biggest enemy.

At any rate, I am happy to see that the answers you are getting here are pretty much the same as the answers you got in the other forum. (For example about the audio samples you posted, about passive splitting of your mic signal, about hiss reduction, etc.) Hopefully this will start to make sense soon and you will be able to accept all this information.

You have said that you are a novice, and it's good that you are asking questions! It's unfortunate that you can't find someone locally to help you with this. (By the way, where are you?) When I first became interested in audio I tried to learn a lot by reading, but the learning process was very slow. As you see, there are many inter-related issues, and asking a question about one of them will lead to many more questions. For myself, at least, I found that having someone who could sit down, draw a few pictures, and actually demonstrate things in person, made the learning process a lot faster.

Meanwhile, Good luck!

Excuse me for butting in, but I believe his original post said the mic was 8" from the subject... inches, not feet. That would be a bit less troublesome.

Just wiring the two inputs to the mic in parallel with each other without any active components, transformers, etc to isolate them from possibly interacting with each other If the mixer has two independent sets of outputs, then yes it will. But if there's only one set of outputs, you still have the issue of the two inputs you need to send the signal to getting wired togther in parallel with each other. My SD mixer has several sets of outputs that are all isolated from one another with transformers - it would work just fine for what you need. Whether your Samson will is anybody's guess without knowing whixh mixer you're considering in order to look up its specs.

Yes I misread 8 feet instead of 8 inches. Certainly that will make an improvement. However depending on the room acoustics, the PA system and how the loudspeakers are placed, a shotgun mic (even one that's relatively smooth like the AT897) can have such unusual frequency peaks that feedback will still be more of a problem than with a cardioid vocal mic.

Sure, a few unpredictable hard-surface reflections and everything will get very difficult.

I think he'd be better keeping the recording system entirely separate from the PA system. Certainly, trying a passive split between a battery mic, an unbalanced recorder, and a (probably) balanced PA system is just asking for problems.

It's interesting, because in one of Syed's original posts, he says yes, there is a PA system, but he does not want to record from it... he wants to stay separate. But then later he says he wants to use a single mic and split it for recording and PA. I think he is floundering around and doesn't have a clear sense of direction right now.

If the PA people use a good close-work PA mic for the talent, they can hopefully keep their gain and feedback under control. Then if Syed really wants to use a shotgun 8" away, he can do that, without causing any potential PA problems. He will have enough trouble recording, as it is, given that his recorder has no level meter and no gain control (just a "mic sensitivity" switch).

There's a lot to be said for KISS.

Re: Audio Technica AT897 with small consumer grade low end DVR
 

I was busy, I was changing my home. With your help I almost done my project, thank you Greg, Steve, Jay .et al for all help and support.

As I told you before I will not use PA system i.e. it is not my primary concern to feed both (PA system and my recorder) through my microphone. I was just asking if I found that type of situation, which way I would go. But now I found that there are a lot of subtle things which I need to learn to handle that type of dual feeding. Mostly I’m anticipating there is a lavaliere available for PA, and I can use my mic upon podium or on stand. So right now I can leave it.

Now perhaps I have last four questions:

1. How can I clean my audio effectively?
2. How can I increase the gain of my audio via software?
3. How to compress my resultant audio or video?
4. Is there any consideration w.r.t Youtubing or Podcasting it?

1. How can I clean my audio effectively?

My audio have 400 Hz hum and room noise. This is before the cleaning:

http://www.dvinfo.net/forum/attachme...1&d=1299927154

I removed the hum as:

http://www.dvinfo.net/forum/attachme...1&d=1299927154

Base freq= 462.01 Hz
Filter Q = 163.72
Num Harmonics = 1
Harmonic slope = 0
Harmonic gain = -80dB


Then I cleaned the ambient noise as:

http://www.dvinfo.net/forum/attachme...1&d=1299927154

Tonal & Broadband Threshold = 0.2 dB
Tonal & Broadband Reduction = 40 dB
Musical Nosie Suppr. = 10
Residual Whitening = 0

I used this preset two times, and got these results:

http://www.dvinfo.net/forum/attachme...1&d=1299927154

Greg can you tell me how you cleaned my clip. My resultant sound is relatively robotic especially for more distant sounds. Please help me. And what is called distortion, as you told me that my edited sound is much distorted, I think my original edited sound, and consequently its video isn't much distorted as you can hear:

Audio: https://tqzvbg.blu.livefilestore.com...ownload&psid=1,

Video or:
https://tqzvbg.blu.livefilestore.com...ownload&psid=1

But YouTubed video is slightly distorted:
YouTube - High Sensitivity LFC No 80Hz 2x Denosing 17.08 Gain *

How can I clean my audio effectively?*

2. How can I increase the gain?*

Greg as I told you I was 8" away and I think I was talking in normal loudness; however the gain of my recording is low.
*
The gain of my recoded file is b/w -10 dB to -3 dB, while the file format is .mp3 and file size is 1.19 MB for 52sec. This is the file: https://tqzvbg.blu.livefilestore.com...ownload&psid=1

Screen shot of iZotope:
http://www.dvinfo.net/forum/attachme...1&d=1299927154


But when I tried to increase the gain from -6dB to +17.08 dB, in comparison to BBC podcast, iZoptope created the wave file from my mp3 and file size is 17.5 MB for 52sec. This is the file:
https://tqzvbg.blu.livefilestore.com...ownload&psid=1

How can and how much should I increase the gain? Which is appropriate for YouTube? Or for podcast?

3. How to compress my resultant audio or video?

And other problem is that the audio file size is too big (1.19 MB vs. 17.5 MB for 52sec), how can I compress it. when I tried to compress the above mentioned 17.5 MB audio file back to mp3, it was sounding me weird, Here is the file:
https://tqzvbg.blu.livefilestore.com...ownload&psid=1

How can I compress it without damaging my sound? Do I need a software compressor?

4. Is there any consideration w.r.t Youtubing or Podcasting it?

Consequently when I made the video using image and edited wav file (17 MB) through Sony Vegas Pro 10. It gives me lots of "Render As" options. I rendered it in three different formats:

189 MB .avi format (Good in quality)
16.9 MB real player format (.rm) (Good in quality)
2.47 MB .wmv format (ruined my voice)

Also when I uploaded them on YouTube, the audio quality was slightly decreased.

Then what is the most appropriate format in which I should render it? With respect to Youtubing or Podcasting.

Re: Audio Technica AT897 with small consumer grade low end DVR
 

Syed:

1.) I don't remember what I did to clean your file. That was over a month ago. I could have told you at the time but I have forgotten. I'm really not interested in doing it again.

2.) What program are you using for all your attempts?

3.) You are trying to correct for many problems: incorrect levels, noise, distortion. Many of these are caused by using the wrong recorder. You are just wasting a huge amount of time by doing this.

Besides, many of the above links do not work when I click them.

We have a saying: "You can't make a silk purse out of a cow's ear." In other words, if you start with a tough and ugly piece of leather, you cannot turn it into something smooth and beautiful. I think that this largely applies to your situation.

However, please answer the above question and perhaps we can have a better outcome.

Re: Audio Technica AT897 with small consumer grade low end DVR
 

I'm using:

iZotope RX Advanced (v. 1.30.768) for Cleaning
Sony Vegas Pro 10.0c for video making


I'm understanding my situation and as soon as I can I'll buy some prosumer equipment, as you guys suggested me.

But unfortunately for first few projects I have to relay on this system. And I want to make it load and clean, in some acceptable extant.

I'm exporting my iZoptope presets which I used to clean my audio, you may check them:

Denoiser, Hum Removal Presets:
http://www.dvinfo.net/forum/attachme...1&d=1300881703


And I increase the gain through iZotope "Gain" process from -6dB to +17.08 dB. But I found unacceptable increase of size of wav file.

As you told me the audio was cleaned too much, and have great distortion, Do you think the lowering of these settings can assist me?

But the size of wav file is still an issue, I don't have any solution.

Re: Audio Technica AT897 with small consumer grade low end DVR
 

"The size of wav file is still an issue, I don't have any solution"
> The size of .wav file should NOT be an issue unless your HD(s) are full. It will be encoded to the proper format (if needed) when the project is rendered for DVD or other formats.
By default, Vegas creates a PCM audio proxy file anyway when lossy file types are added to the timeline.