Micro budget field mixer and mics

[Nick Mirro]

I'm a beginner to xlr sound with a very small budget and I am wondering if these two mics would work with the inexpensive field mixer below. The goal is to combine 2 channels of stereo from the stereo lapel mic (that I have) with the output from the Audio Technica.

Will the mics below work with this mixer?

I know this is low budget cobbled together rig, but it is all I have. Thanks for any help!


ROLLS MX124

http://tinyurl.com/c8bavhc

Input Connections 4 - 3-pin XLR female
Output Connectors 2 - 3-pin XLR male
Max Input/Output Gain +55dB
Input Impedance: 600 Ohms
Output Impedance: XLR 500 Ohms
Signal-to-Noise Ratio 84dB
Phantom Power +18V DC
AC Power Requirements x2 9-Volt Alkaline Batteries
Current Draw: 30mA
Dimensions 6.3 x 2.3 x 3.7" (160 x 58.41 x 93.98mm) (WxHxD)
Weight 1.5 lbs (680.38 g)


AUDIO TECHNICA AT875

Transducer Fixed-charge back plate, permanently polarized condenser
Polar Pattern Line + gradient
Frequency Response 90Hz - 20,000Hz
Dynamic Range (Typical) 107 dB, 1 kHz at Max SPL
Sensitivity -30 dB (31.6 mV) re 1V at 1 Pa
Impedance 100 ohms
Signal-to-Noise Ratio RATIO 74 dB, 1 kHz at 1 Pa
Maximum Input Sound Level 127 dB SPL, 1 kHz at 1% T.H.D.
Power Requirements 11-52V DC, 2 mA typical
Output Impedance 100 ohms
Output Connectors Integral 3-pin XLRM-type
Phantom Power 11-52VDC, 2 mA typical
Dimensions 6.89" (175.0mm) Long
0.83" (21.0mm) Diameter
Weight 2.8 oz (80 g)


Olympus ME51S

http://tinyurl.com/8wlpoym

(using a Y-adapter)

Type Stereo Electret Condenser Microphone
Frequency Response 100Hz - 15kHz
Directivity Uni-directional x 2
Sensitivity -40dB @ 1kHz
Impedance 2.2 kOhms
Plug 3.5mm Stereo
Power Supply Plug-in-power System (1.5V - 10V)
Dimensions (L x B x H)
1.5 x 0.55 x 1.6" (38 x 14 x 40mm)
Weight 0.24 oz (7 g), 0.6 oz (18 g) with cable and clip

 

[Alex H.]

What do you hope to accomplish? Or, what are your needs, and what kind of recording are you doing? Nature recording? Dialog for narrative work? Seated interviews?

The mixer: that Rolls has no metering, only a rudimentary signal and clip indicator. That leaves you with no real way of watching your signal levels to keep them in check.

The shotgun: the AT875 is an okay mic, but how do you intend to use it? A shotgun isn't going to do you much good without some support and protection. In other words, shock mount, windscreen, boom pole. What about cables?

The Olympus mic: what do you intend to do with this? Stereo mics like this aren't very useful for many things, so I wonder why you included this?

Also, to what kind of device are you recording? Will you be feeding the mixer's outputs into a camera? A recorder? And have you accounted for headphones, which are absolutely critical for sound?

And you say you want to combine the sound from the stereo "lav" with the sound from the shotgun. Why? What effect are you going for there? Never mix mics in the field if you don't have to. Record them separately so you can control the mix in post. Of course, how you split mics in the mixer depends on what kind of recording device you're using.

 

[Nick Mirro]

Thanks Alex. Here are some answers.

Just found out the Olympus mic is not compatible without some major body-shop work. I can't do that so on to another option.

I'm shooting wildlife vids (no serious production) and wish to have the option of narrating in the field as needed. Still new at post processing and will eventually narrate there more.

The camcorder is a Canon XA10 with 2 xlr inputs and a decent shotgun mic holder.

The Audio Techica will have wind protection. Have some practice avoiding wind noise with my prior cheap Canon HG10 and its add-on shotgun mic.

The mixer will have 2 mics as xlr inputs and its output will go to the camera's 2 xlrs.

One mic is shotgun and the other is a compromise. For the second mic (the compromise) I want to narrate and pick up ambient sounds (birds, bugs and wind). So the idea of either a stereo lav mic (now gave up on this ) or maybe a pair of twisted xlr mono (omnidirectional) lav mics is appealing. Though there will be compromise by combining my voice with ambient stereo sounds, equipment budget is probably forcing this part.

 

[Alex H.]

Okay, we have some work to do!

The camcorder is a Canon XA10 with 2 xlr inputs and a decent shotgun mic holder.

So you have a camera with XLR ins, phantom power, and a pretty respectable audio capability.

The Audio Techica will have wind protection. Have some practice avoiding wind noise with my prior cheap Canon HG10 and its add-on shotgun mic.

For what you're doing, a shotgun may or may not be necessary. It can be good for focusing in a little on specific sounds, but don't let myths about the directionality of shotgun mics fool you. These are not the "zoom lenses" of mics. Rather, they are able to reject most sound from the sides and rear, but the rule for any mic for clear, up-front sound is "the closer the better."

That said, the built-in mics on most cameras are generally useless. On-camera is typically the last place you'd want to put a mic anyway, because it can pick up sounds of the camera and camera operator (especially if it isn't properly shock-mounted). But, you're shooting nature stuff, and the shotgun can be at least an improvement on the built-ins.

The mixer will have 2 mics as xlr inputs and its output will go to the camera's 2 xlrs.

You have a camera with very capable audio inputs. Adding a mixer might not need to be a top priority for you right now. In fact, adding a cheap mixer like that Rolls isn't really going to do you any favors.

Here's what I'd suggest: get the AT875 (and good wind protection... a furry windscreen), but get a TASCAM DR-40 instead of the Rolls. This recorder will give you built-in stereo mics that actually do a decent job at recording ambient sounds, much better than that little Olympus you were considering. Get a RedHead windscreen for it as well... that's a must (and not terribly expensive). The DR-40 also has XLR ins with phantom power, so you can use the shotgun mic with it as well.

You can run the recorder separately from the camera. The beauty of video and film production is that not all sounds have to be recorded at the same time as the pictures since they can be put together in post. In fact, it can be helpful to do them separately. Get your stereo ambient recordings from the DR-40. Use the shotgun on your camera for targeted sounds where you need to... or even the shotgun with the DR-40.

With the money you don't spend on the Rolls or the Olympus, the cost about evens out with the DR-40.

Oh... and buy headphones. Good ones. And use them.

One mic is shotgun and the other is a compromise. For the second mic (the compromise) I want to narrate and pick up ambient sounds (birds, bugs and wind). So the idea of either a stereo lav mic (now gave up on this ) or maybe a pair of twisted xlr mono (omnidirectional) lav mics is appealing. Though there will be compromise by combining my voice with ambient stereo sounds, equipment budget is probably forcing this part.

Narration and ambient sound: these are two very distinct purposes that require very distinct mics. And you'd need two different record levels between talking and listening in order to record both (yes, the mixer can help with this, but both will suffer due to drastic level adjustment... so again, forget the mixer). Plus, the mic will be clipped to you and will record your shirt, your breathing, your walking, your turning around... all while you're trying to capture those birds off in the distance. You cannot multitask a mic very well that way.

Unless you're going to be in front of the camera, why do you need to talk while you're recording?

Skip narration in the field, and focus on your ambient sounds. Adding narration (VO, or "voice-over") in post is really, really easy. You can use your camera, or a separate recorder, to record your voice and then add those audio files in under the video. What NLE (video editing software) are you using, by the way?

 

[Nick Mirro]

This is really helpful. Thanks!

One problem is that I often make lots of short clips (e.g. many macro clips using a Canon 500D diopter) and talk about the subject live in an interactive way. This means that while adding audio is a simple matter, there are usually 20 or so clips per outing, so this approach will add work. DR-40 still looks like a must-have.

Also hoping to improve my past problem voice level variation, as my head repeatedly moves near and away from the camera as I interact with close-up subjects. This has been a problem.

The camera cannot mix input from xlrs and other terminals. This rules out using the MIC terminal for a lav (mixed with xlr input), and hence my problem.

This will probably not sit well with you - since you seem to be used to doing things the right way. What do you think of a couple of braided omni lav mics clipped to my shirt, that also pick up ambient? That way I get stereo ambient and my voice (and shirt noises) at a fixed distance.

Worse yet, I am aiming for inexpensive ones - budget is really tight for this.

173 shotgun
134 mixer
307

93 left. If a battery box would allow the Olympus mic to work, I would accept the reduced audio quality as an cost of being cheap. Maybe the battery box would not protect this mic from being fried by the mixer phantom power. Doesn't look like the cheapo Rolls can shut that off.

Maybe 2 used lav mics in ebay? Any model suggestions or are you not liking this?

 

[Alex H.]

1) Two omni lavs wrapped together are effectively the same as the Olympus you were looking at, which is two separate mic capsules in a single housing wired to send two signals (left and right) down a single cable. Either way, it's useless. To use omni mics for a stereo mic array, they have to be spaced much farther apart than... well, right next to each other.

2) Narration as you shoot is still a bad idea, especially if you're trying to multi-task that one mic (or "stereo" pair of mics) to capture narration and ambiance, and to multitask yourself with recording audio and operating the camera.

3) I'm not sure what you mean by

The camera cannot mix input from xlrs and other terminals. This rules out using the MIC terminal for a lav (mixed with xlr input), and hence my problem.

Theoretically, you could have a lav (mono... one capsule... none of that "stereo" nonesnse) into XLR 1 and the shotgun into XLR 2. They record separately, and you use the editing process to mix them together. Add in the stereo recordings you get from the DR-40 and you can create a decent soundscape.

4) Again, recording your narration in post gives you much more flexibility. You have the flexibility between the camera and the DR-40 to capture much more pure sounds of your subjects without bleed-through of your voice. Then, you have the flexibility to record your VO without worrying about proximity to the camera or mic, to get it perfectly right, and to talk cohesively about an edited sequence of clips.

5) The shotgun, as I said before, is not going to be a miracle worker for getting distant sounds. It can help some, but without placing a wireless mic close to where the subject is (or where you anticipate it to be, since we are talking animals in the wild)... or without a parabolic mic (read: $$$)... you just won't be able to get close in on anything. The side and rear rejection will allow you to hone in on sounds in a way, but distant sounds will still sound... distant.

6) Build your basic kit from the shotgun, the DR-40 recorder, proper (furry) windscreens for both, and a good set of headphones. That will get you in a good place to handle nature recording in the field and VO work in post.

 

[Steve House]

...
One mic is shotgun and the other is a compromise. For the second mic (the compromise) I want to narrate and pick up ambient sounds (birds, bugs and wind). So the idea of either a stereo lav mic (now gave up on this ) or maybe a pair of twisted xlr mono (omnidirectional) lav mics is appealing. Though there will be compromise by combining my voice with ambient stereo sounds, equipment budget is probably forcing this part.

Simply recording two microphones into two channels and playing the result through two speakers DOES NOT make a recording stereo. The mic capsules themselves must be oriented to each other and to the sound source in one of several specific geometries in order for the recording to create a stereo effect. Tie-bar lav clips with mounting points for two microphone capsules are common as dirt - a glance at virtually any TV news program will show them in use on the anchors - but the resulting 2-channel mic arrangement is NOT a stereo mic setup. In that application it is used to give two mono audio feeds, a primary and a backup, in case something craps out in one chain during a live show. Using two lavs on your lapel as you shoot your wildlife WILL NOT give you a stereo recording of the ambiance because they won't be in a proper orientation to each other or to the sound source to recreate a stereo soundstage but rather you'll end up with two essentially identical mono tracks. You can accomplish the same result by recording with one mic on on a single mono track and centre panning the resulting track in your editing software so it comes out of both stereo speakers during playback.

If you're interested, here's a link to a pdf file on the Schoeps microphone website that diagrams and explains several common arrangements and microphone pickup patterns that two mics need to be in so as to record real stereo. You'll see that two lavs twisted together or mounted side-by-side don't fit any of them. http://www.schoeps.de/documents/stereo-recording-techniques-e.pdf

Having two lavs on you lapel won't pickup ambiance any better than would just one. Since you're not going to get stereo with two lavs side-by-side anyway, why not simplify. Send your shotgun to one XLR input on the camera. Get a single phantom-powered lav mic with an XLR connector, clip it to your lapel, and send it into the 2nd XLR input on your camera. You'll get just as good a result as you would trying to use your Oly stereo microphone or your twist lavs notion without all the muss 'n fuss.

Be aware that if your shotgun is on the camera and you try to talk while shooting in order to record commentary as you say you want to do, your voice WILL be picked up by the shotgun and with the gain on that channel turned up in order to hear the faint distant animal sounds you want to capture, your voice's volume will be overwhelming and completely obscure the animals.

 

[Nick Mirro]

Just erased my reply. When using quick reply, watch out for the "post reply" button!

Thanks for the info Steve. I appreciate your digging into my line of reasoning.

Regarding stereo separation, I decided to perform a test, using a digital recorder and playing back with decent Grado headphones.

The test was as follows. One recording was made at mono and I slowly turned the recorder around. The result was as expected, with the sound seeming to originate in the center of my head and having a drab quality.

Next I attached the Olympus microphone and recorded in stereo, from the same spot and with the exact same motion. The result was drastically different. There is a fountain that is about 50 feet away from where I stood. As I turned, playback revealed that the fountain traveled around me in three-dimensional space. I then recorded my voice 3 feet from the microphone on one side, and then the other. When speaking to the left side of this stereo Mike, my voice was barely detected in playback on the right channel. Yet it was crystal clear on the side on which I spoke. The stereo recording had a clear and pleasing three-dimensional quality with much better separation then even I expected.

Of course there is probably no way to use this mic since Phantom power would fry it. I guess a battery box would make it operational, but is it correct that there is no way to block Phantom power coming from the mixer?

Would you expect a different test result if I were to rig together to different mono (omnidirectional) lav mics?

 

[Alex H.]

Okay, a few things:

Looking closer at the Olympus, it looks like two cardioid elements. So, yes... you'll get some sort of stereo imaging out of that. Using two omnidirectional lavs, as you suggested above, will do nothing for you at all. Your test, however, gives nothing of use: you recorded in mono mode, and got a mono recording. There should be no surprise here. You recorded with a "stereo" mic and got some wider imaging. Again, there should be no surprise here.

That Olympus really needs to be taken out of the equation. Placing a stereo "lav" on yourself and trying to get dialog and ambiance at the same time is a waste of time and effort. Also, the mic is not compatible with power supplies from most mixers and recorders. Trying to adapt it around that is going to have a negative impact on what signal quality that $40 mic is able to produce in the first place.

Dialog, whether for dramatic narrative, documentary, newsmagazine, or whathaveyou, is a mono source. Period. You don't want to record dialog in stereo at all. If you really, really must record your voice while in the field, which you've been advised against several times, your best bet is an omni lav with XLR termination feeding straight into the camera. Get the DR-40 and use it for stereo ambiance, which can be recorded separately from the video and laid into the edit later.

Half of the fun of creating in video and film is creating the world through sound. You take the track with your shotgun mic's audio and mix it in post with stereo ambient recordings and, if you really are determined to record it, your "narration". All these elements come together in the end to create a complete image.

 

[Noiz2]

Nick,

Maybe you should define what it is you want to do.

Of course using stereo will give you a wide field on headphones (very expensive headphones at that), but is that relevant?

Unless your audience is exclusively going to be watching your show on headphones then NO, it's not relevant.

It sounds like you are doing some sort of art project. If that is the case none of the "rules" apply. If your trying to do a show that "works" in a theatre and on TV etc. then you need to keep the dialog mono and centered. Really if YOU are not what the piece is about then how "exciting" you think your voice is is irrelevant.

Headphones are basically useless for anything but monitoring and rough editing in a pinch. OR if you are ONLY going to deliver for a headphone audience. LOTS of things (perceptually) change with headphones VS speakers.

Now if this is a performance art piece where you can mandate that folks only listen through headphones AND it's all about you then do whatever you want because all that really maters in that case is you like the result.

You really need to define this or folks who would give you advice (based on a normal show) are going to get pissed off and ignore you. Not because they think what you are doing is wrong but because you are not "hearing" them.

SO if your trying to do a mainstream show then listen to the advice it's good. If your doing performance art ask about hardware and specifics.