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-   -   Is stereo necessary? Rode NT4 for documentary, interviews... (https://www.dvinfo.net/forum/all-things-audio/67736-stereo-necessary-rode-nt4-documentary-interviews.html)

Stu Holmes May 25th, 2006 02:34 PM

If Rycote fails, try Reinhardt :

http://www.reinhardt-film.com/products.php

they make a lot of windshield for all kinds of unlilkely mics.
They'll be able to make one up for the Sony i'm sure. They even say to email them with your request :
info@reinhardt-film.com

hope this helps

Ray Ambrosi May 26th, 2006 03:28 PM

Sony ECM-MS957 or Rode NT4
 
Thanks everyone for the feedback

Everyone posted a lot of good info. Thanks!

I check out prices an M-S stereo AT835ST will cost about $600 and so will the SURE VP88. That's over my budget! So as far as M-S mics go, the only one I can afford is the Sony ECM-MS957

It seems like I can only afford X-Y stereo. So I'll have to choose between the AT825 stereo or the Rode NT4. Or I can go with the cheap Sony ECM-MS957 M-S mic. Any recommendations?

Rodger had asked which Beachtek I am using. I will be using DXA-8 that supplies phantom power. It will be used either on the mindisc equip or with my video camera. I will also use DXA-2 on the remaining equipment.

There is a company advertising on Ebay that can make furry covers for any mic. Is there any difference in these furry covers? I mean, does the quality or performance differ?

Steve House May 26th, 2006 04:22 PM

Quote:

Originally Posted by Ray Ambrosi
Thanks everyone for the feedback

Everyone posted a lot of good info. Thanks!

I check out prices an M-S stereo AT835ST will cost about $600 and so will the SURE VP88. That's over my budget! So as far as M-S mics go, the only one I can afford is the Sony ECM-MS957

It seems like I can only afford X-Y stereo. So I'll have to choose between the AT825 stereo or the Rode NT4. Or I can go with the cheap Sony ECM-MS957 M-S mic. Any recommendations?

Rodger had asked which Beachtek I am using. I will be using DXA-8 that supplies phantom power. It will be used either on the mindisc equip or with my video camera. I will also use DXA-2 on the remaining equipment.

There is a company advertising on Ebay that can make furry covers for any mic. Is there any difference in these furry covers? I mean, does the quality or performance differ?

Just a thought - the NT-4 is essentially two NT-5 cardioid heads mounted together. If you were to get a stereo matched pair of NT-5's you'd get two mics for a total cost that is actually a few dollars less than the NT-4. A stereo bar would let you put them on a stand for X-Y recording just like the NT-4 but with the additional flexibility of other mic placements like ORTF, A-B, etc, or to use them singly for interviews, instrument mics, etc. If one of them craps out on you on location, you still have the other so you can at least record in mono while if all you have is the NT-4 and it fails, you're toast. When traveling light the more different things a single piece of gear is capable of doing the better off you are. Two mics that can be used either together or separately in a variety of jobs is a better bang for the buck spent than 1 mic that is fairly specialized. Of course, the NT-5s don't have a battery and required phantom so that might be an issue but if you have the Beachtek along it's not a big deal.

Gian Pablo Villamil May 26th, 2006 05:20 PM

Whatever you get, you should check out this free software: http://www.voxengo.com/product/msed/

It is an M-S to L-R encoder/decoder in a VST plugin. So you can run it in Vegas Video, for example, and any other editing software that accepts VST.

It decodes M-S to L-R, allowing you to control spatialization, and encodes L-R to M-S (the other way round). It also has an "inline" mode, which simulates putting two instances of the plugin in sequence, hence allowing you to adjust mid-side values even if your source is L-R stereo. It is very cool!

Jon Fairhurst May 26th, 2006 07:07 PM

Nice tip on the MSED software.

Here's what I'm thinking of doing on my next production: I'd like to record a mono shotgun and a M-S pair simultaneously. The shotgun is for the talent, and I'd stomp on it with noise reduction. I'd add back in some ambience from the M-S pair.

The idea is that the shotgun with noise reduction and EQ will get me the cleanest dialog. I only need mono, as I'd keep it in the center. With a nice clean signal, I can ride the levels syllable by syllable, if needed.

The M-S is for the ambient noise tracks. I'd keep it away from the talent. I'd EQ out the primary dialog frequencies to dampen the dialog, and phase align it with the shotgun as best I could. If I still get phase problem with the dialog, I'd just loop some quiet parts behind the dialog with a wide stereo spread. If I need the ambience to be sync'd with the video, I'd just mix it down low enough that the phase problems aren't too bad.

This technique should give a clean dialog track, a natural, wide stereo ambience without the hollowness of a shotgun, and the ability to mix down to mono without phase issues.

I'm working theoretically on this. Does anybody have any practical experience with this technique?

-Jon Fairhurst
http://PoorlyProjectedPictures.com

Dave Largent May 26th, 2006 07:45 PM

Quote:

Originally Posted by Jon Fairhurst
This technique should give a clean dialog track, a natural, wide stereo ambience without the hollowness of a shotgun
http://PoorlyProjectedPictures.com

Not sure I understand. You plan on using two separate mic's?
Three separate mic's ("shotgun plus M-S pair")?
It seems to me you'd still have that
hollowness if you are using a shotgun, either if it's an
M-S mic or not.

Jon Fairhurst May 26th, 2006 08:18 PM

The M-S would be a standard condenser mic. Not a shotgun.

The reason a shotgun sounds hollow in a small room is because the ambience loses its highs. Only the direct signal has a flat(ish) frequency curve. By using noise reduction, you get rid of a lot of the dull ambient noise from the shotgun. By mixing in some flat ambience from the M-S mic you get back to a more normal sounding environment.

* Clean dialog in the center
* Flat, controllable ambience at the sides
* The ability to mix down to mono without phase problems

Does that make sense?

Something like this would work...
http://www.studioprojectsusa.com/lsd2.html

Though, I'll probably go for two cheaper large condensers with switchable patterns and a couple of stands. The large condensers can do double duty for studio voiceovers.

You certainly won't get a hollow ambience from large condenser mics. My only real concern relates to phase issues when mixing this in with the processed shotgun.

Maybe the best solution - especially if you only have a stereo recorder - is to record "silence" with the m-s pair before/after the shoot and use it as a pad underneath the noise reduced mono shotgun track.

-Jon Fairhurst
http://PoorlyProjected Pictures.com

Dave Largent May 26th, 2006 10:38 PM

[QUOTE=Jon Fairhurst]The reason a shotgun sounds hollow in a small room is because the ambience loses its highs.http://PoorlyProjected Pictures.com[/QUOTE

You sure about that? That's not how I'd describe
the hallowness, such as you say "the ambiance
loses its highs". I could be wrong but it sounds
to me more like a reverb effect such as "inside
a tank".

Douglas Spotted Eagle May 26th, 2006 11:11 PM

Since shotguns become omni's in the low frequencies, the low frequencies are enhanced, and maybe this is being perceived as a lack in high freq's vs the actual bump in the low mid and low?

Ray Ambrosi May 27th, 2006 12:31 AM

Quote:

Originally Posted by Gian Pablo Villamil
Whatever you get, you should check out this free software: http://www.voxengo.com/product/msed/

It is an M-S to L-R encoder/decoder in a VST plugin. So you can run it in Vegas Video, for example, and any other editing software that accepts VST.

It decodes M-S to L-R, allowing you to control spatialization, and encodes L-R to M-S (the other way round). It also has an "inline" mode, which simulates putting two instances of the plugin in sequence, hence allowing you to adjust mid-side values even if your source is L-R stereo. It is very cool!

Thanks Gian! I'm pretty new to all this so I have had to do a lot of reading where I can and will need a crash course in audio recording before I head off to do my project.

That software sounds interesting, but I'm not sure exactly what it does, or what advantages it offers. Could I use that software with the Sony ECM-MS957? Can anyone tell me if the specs on this mic are good or not? Any practical experience? Should I make a new posting? I really do want to find out if the Sony is worth buying and whether it can provide the type of M-S recording that can be manipulated to bring out the sounds and degree of stereo separation that I want to emphasize (this is the advantage of M-S as I understand it). Please advise!!

Quote:

Originally Posted by Steve House
Just a thought - the NT-4 is essentially two NT-5 cardioid heads mounted together. If you were to get a stereo matched pair of NT-5's you'd get two mics for a total cost that is actually a few dollars less than the NT-4. A stereo bar would let you put them on a stand for X-Y recording just like the NT-4 but with the additional flexibility of other mic placements like ORTF, A-B, etc, or to use them singly for interviews, instrument mics, etc. If one of them craps out on you on location, you still have the other so you can at least record in mono while if all you have is the NT-4 and it fails, you're toast. When traveling light the more different things a single piece of gear is capable of doing the better off you are. Two mics that can be used either together or separately in a variety of jobs is a better bang for the buck spent than 1 mic that is fairly specialized. Of course, the NT-5s don't have a battery and required phantom so that might be an issue but if you have the Beachtek along it's not a big deal.

Thanks for that suggestion Steve. It sounds like a good idea. I think I'd use two Rode NT3 mics because they can run on an internal 9v. (yes I'm fairly obsessed with the mikes having an internal battery). The only problem with putting them on a stereo bar is that I'd have to set it up each time I want to use it. Is it hard to get the mic placement correct? Would the NT5 mics sound much better than 2 NT3 mics? I had planned to use either my Rode NTG-2 shotgun on my video camera to focus on the person speaking and the stereo mic on the MD recorder to capture the ambient sound. Or is should I use another arrangement? So I was thinking I could get away with only carrying 2 mics to save weight and bulk.

Dave Largent May 27th, 2006 01:04 AM

Quote:

Originally Posted by Douglas Spotted Eagle
Since shotguns become omni's in the low frequencies


Is this true of the cards and hypers as well?

Steve House May 27th, 2006 01:57 AM

Quote:

Originally Posted by Dave Largent
Is this true of the cards and hypers as well?

No. While pressure gradient microphones like cardioid and hypers do exhibit a "proximity effect" where bass is boosted at close working distances, their directivity is not frequency dependent. They develop their directivity on the pressure differences caused by sound waves arriving at both the front and back of the diaphram. Shotguns use a line-gradient principal with a pressure transducer (an omni capsule) located at the bottom of a tuned interferenece tube. Sound waves enter the tube through the front and at the various ports on the tube. Those coming from the front are in phase with the portion of the same sound wave entering through a side port. But sounds arriving from the sides and rear enter the tubes from the ports and from the front at slightly different times so there's a phase difference between the portion of the wave from the side port and the portion from the front port. As these two portions of the sound wave travel through the tube to the diaphram they interact with each other inside the tuned tube and cancel each other out. Since it is the wave interactions inside the tuned tube that does the work they are dependent on the frequency of the sound and the dimensions of tube, just like the tone of an organ pipe is dependent on its dimensions. Off-axis high and mid frequencies are affected much more than are low frequencies from the same directions because low frequency wavelengths are too long to be affected very much by the tube. As a result off-axis mids and highs are supressed while lows from all directions reach the diaphram undiminished.

Gian Pablo Villamil May 27th, 2006 02:05 AM

Quote:

Originally Posted by Ray Ambrosi
...That software sounds interesting, but I'm not sure exactly what it does, or what advantages it offers. Could I use that software with the Sony ECM-MS957? ...

It is a plugin that works within most audio applications, and some video applications. Basically it takes two channels of audio, recorded as mid and side, and converts it to left and right stereo. In the process, it lets you vary the mix between mid and side, to achieve more of a "wide" stereo ambiance, or a more "narrow" ambiance.

It can also do the reverse transformation - extract mid and side information from a left/right recording. Finally, it does the equivalent of sticking two instances of the plugin in a row - encoding L/R stereo as mid/side, adjusting the mid/side balance, then re-encoding it back to L/R. So starting with a conventional L/R stereo recording you can modify the apparent spatial distribution.

It will work with any mid/side mike or any L/R stereo mike. You might need to invert the phase of one channel, but that is easy to do.

Steve House May 27th, 2006 02:25 AM

Quote:

Originally Posted by Ray Ambrosi
...
That software sounds interesting, but I'm not sure exactly what it does, or what advantages it offers. Could I use that software with the Sony ECM-MS957? Can anyone tell me if the specs on this mic are good or not? I really do want to find out if the Sony is worth buying and whether it can provide the type of M-S recording that can be manipulated to bring out the sounds and degree of stereo separation that I want to emphasize (this is the advantage of M-S as I understand it). Please advise!!
...

While the Sony mic uses the M/S principle to achieve its stereo output, it decodes the signals internally and so its output is conventional L/R stereo. AFAIK you don't have access to the original mid and side signals coming off the individual mic capsules. That means the post recording manipulation that's possible when recording the "raw" mid and side signals is no longer available.

Dave Largent May 27th, 2006 02:26 AM

Quote:

Originally Posted by Gian Pablo Villamil
It can also do the reverse transformation - extract mid and side information from a left/right recording. Finally, it does the equivalent of sticking two instances of the plugin in a row - encoding L/R stereo as mid/side, adjusting the mid/side balance, then re-encoding it back to L/R. So starting with a conventional L/R stereo recording you can modify the apparent spatial distribution.


It can take an X/Y recording and convert it to M-S,
so that you can work with it as you normally would
work with an M-S recording? I'd be curious to
hear what some others here have to say about
this. I guess we don't need M-S mic's anymore.

Dave Largent May 27th, 2006 02:28 AM

Quote:

Originally Posted by Steve House
While the Sony mic uses the M/S principle to achieve its stereo output, it decodes the signals internally and so its output is conventional L/R stereo. AFAIK you don't have access to the original mid and side signals coming off the individual mic capsules. That means the post recording manipulation that's possible when recording the "raw" mid and side signals is no longer available.

Except if you use that program that Gian
recommended ... maybe. For some reason
I feel a bit skeptical about it but I don't
really know.

Steve House May 27th, 2006 05:44 AM

Quote:

Originally Posted by Dave Largent
Except if you use that program that Gian
recommended ... maybe. For some reason
I feel a bit skeptical about it but I don't
really know.

Because the stereo L/R pair is derived from a mid/side signal matrix it can also go the other way.

Mid = (L+R)/2
Side = (L-R)/2

Gian Pablo Villamil May 27th, 2006 06:25 AM

Quote:

Originally Posted by Steve House
Because the stereo L/R pair is derived from a mid/side signal matrix it can also go the other way.

Mid = (L+R)/2
Side = (L-R)/2

Exactly.

If you've ever encoded an MP3 using the joint stereo mode, you've used a type of M/S encoding. See here: http://harmsy.freeuk.com/mostync/

The concern with, say the Sony mike or the AT 835ST in L/R mode, is that they don't do a straight transform between M-S and L-R: they apply multipliers to give the narrow or wide field effects. (It would be nice to know what these multipliers are...) So you'd have to do some tweaking to reconstruct the exact, original M-S inputs. However, since the MSED plugin is doing two symmetrical transforms, you can still use it to tweak "spatialization" of an incoming L-R signal, even if you don't know how that signal was constructed from the original M-S. You're basically applying differences.

David Ennis May 27th, 2006 09:41 AM

Quote:

Originally Posted by Dave Largent
...[The plugin Gian mentioned]...can take an X/Y recording and convert it to M-S,
so that you can work with it as you normally would
work with an M-S recording?...I guess we don't need M-S mic's anymore.

Well, a single point M/S mic would still be a more convenient way to get M/S signals then fiddling to set up an X/Y pair and then deconsrtucting the recording. Plus,the mid and side signals you might extract from any given X/Y pair recording will be different sounding than the corresponding mid and side signals you'd get from any given M/S mic, because different mics are still different mics. However, that doesn't mean that I might not prefer the ultimate result from M/S reprocessing the recordings from my X/Y'd AT3031s over the result from an AT835ST. I don't have an AT835ST to play with, but I just tried the MS encorder plugin on one of my AT3031 pair recordings and I like it a lot. I had been contemplating getting the 835ST but now I don't know....

Steve House May 27th, 2006 10:35 AM

Quote:

Originally Posted by Fred Retread
Well, a single point M/S mic would still be a more convenient way to get M/S signals then fiddling to set up an X/Y pair and then deconsrtucting the recording. Plus,the mid and side signals you might extract from any given X/Y pair recording will be different sounding than the corresponding mid and side signals you'd get from any given M/S mic, because different mics are still different mics. However, that doesn't mean that I might not prefer the ultimate result from M/S reprocessing the recordings from my X/Y'd AT3031s over the result from an AT835ST. I don't have an AT835ST to play with, but I just tried the MS encorder plugin on one of my AT3031 pair recordings and I like it a lot. I had been contemplating getting the 835ST but now I don't know....

The Waves S1 plugin gives you the same image manipulation tools normally associated with M/S using a conventional stereo input. It'll also decode M/S inputs to stereo but doesn't work the other way around.

Ray Ambrosi May 27th, 2006 05:48 PM

Quote:

Originally Posted by Gian Pablo Villamil
Exactly.
The concern with, say the Sony mike or the AT 835ST in L/R mode, is that they don't do a straight transform between M-S and L-R: they apply multipliers to give the narrow or wide field effects. (It would be nice to know what these multipliers are...) So you'd have to do some tweaking to reconstruct the exact, original M-S inputs. However, since the MSED plugin is doing two symmetrical transforms, you can still use it to tweak "spatialization" of an incoming L-R signal, even if you don't know how that signal was constructed from the original M-S. You're basically applying differences.

Thanks Gian. You've explained things in a way that's easy for me to understand. So after reading this, I conclude that considering the high cost of M-S mics, and my need for an internal battery, I'm going to buy a AT825 stereo mic (AA battery and lightweight). If I want to try to get M-S audio, I'll use that piece of software to manipulate the recordings and obtain it. After reading the posts, the AT825 seems to have fewer noise issues than the Rode NT4, and is half the weight. The Sony would be decent perhaps, but it seems that pros doing use it. That seems to be a revealing fact on its performance.

Any opinions about my decision before I go out to buy? Thanks for the rental idea, but at $45 per day, its not worth it for me to rent and I don't know what I'm listening for yet. I'm going to make my decision based on those finely-tuned & experienced ears of the people who know

Gian Pablo Villamil May 27th, 2006 06:30 PM

Here's a thought: get some video you like (maybe a clip from a movie) with stereo sound, drop it into your NLE and use the MSED plugin to fiddle with it. That will give you an idea of what is possible.

For example, copy the stereo tracks. Use the plugin on the original tracks in "inline" mode to drop the gain on the mid and leave only the sides. Use the plugin on the copy in "encode" mode, gain up the mid and kill the side to extract only the center channel. Mix all the tracks together. Experiment with panning the center channel back and forth. You should be able to do stuff like moving only the dialogue from left to right, while the background sound stays put. It's no substitute for actually having a bunch of different mikes, but you can have some fun, and learn some stuff.

David Ennis May 28th, 2006 08:06 AM

BTW, several other of the free VST plugins at that site are nice too--a real time frequency distribution display, a mono to quasi-stereo processor, etc.

Ty Ford May 28th, 2006 10:14 AM

Quote:

Originally Posted by Seth Bloombaum
Yeah, that's the question alright.

In this case, how "line" is line, how "shotgun" is shotgun? Within what looks to be the interference tube of a short shotgun, there's the figure-8 capsule, which must be in the slotted section of the tube, plus the mid capsule... so how much interference tube is left to provide side cancellation to the mid capsule? Does the mid-mic have the (hollow sounding) characterstics of a shotgun when used indoors?

I'm looking for a single-housing M-S mic for primary use indoors. With what I can afford there are really only two I'm aware of, the AT835ST and the Shure VP88. However, I don't know anyone who has either one, nor a retailer in this area, so I'm very interested in Gian Pablo's experience of the AT.

Well there is the Neumann RSM 191 (you will be really upset after hearing it to know you can't afford it). You can get a lot of work done with the 835ST.

I have a review of both in my archive.

Regards,

Ty Ford

David Ennis May 28th, 2006 12:38 PM

Ty, although you found the LF roll off patterns of the ATs interesting I gather that you liked the overall sound of the VP88 better. Is that right?

Seth Bloombaum May 28th, 2006 02:00 PM

Quote:

Originally Posted by Ty Ford
Well there is the Neumann RSM 191 (you will be really upset after hearing it to know you can't afford it). You can get a lot of work done with the 835ST.

I have a review of both in my archive.

Regards,

Ty Ford

Ty, thanks for the advice. I *have* employed a sound engineer who has the RSM 191, it is an awesome mic that I would love to use all the time, but no, I can't afford to purchase one!

I'll check out your reviews.

Ty Ford May 28th, 2006 04:49 PM

Quote:

Ty, although you found the LF roll off patterns of the ATs interesting I gather that you liked the overall sound of the VP88 better. Is that right?
Well the problem is I didn't review them at the same time so I can't respond directly in a A/B sort of way.

I do remember that the wider settings of the VP88 resulted in noticeably more noise (presumably from the gain being turned up on the side capsule.)

Regards,

Ty


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