Wireless system with two lav mics

[Juha Nurminen]

I am looking for a wireless audio system to use with my Sony a7s. I would need a system which can record a conversation of two people, both wearing lavalier mics. I would be connecting it directly to the camera or alternatively through a Juicedlink preamp I already have.

The cheapest solution would be to get two wired lav mics and connect each of them to a corresponding iphone the person is wearing. This would obviously require a lot of lipsyncing in post with two different audio tracks from two recorders.

I was also thinking of getting two Rodelink systems as they are quite cheap. However, I am not sure if there would be conficts with two simultaneous sytems. Has anyone experience of using two Rodelinks with the same camera?

The simplest alternative would be to get an Audio-Technica ATW 1800 sytem with a dual-channel receiver. However it costs almost twice the price of two Rodelinks and I am not sure where to find one as I live in France.

I would appreciate any thoughts and expereinces from anyone already using a system with two lav mics.

[Richard Crowley]

You did not reveal any details here that would explain why you think you need a WIRELESS solution at all?

Yes, using separate recorders for each subject would require syncing, but there are several additional problems with that method. I created a matrix of trade-off factors here:
DVXuser.com -- The online community for filmmaking - Article: Audio Solutions Matrix...Advantages/Disadvantages

Rode's information on their wireless kits are remarkably void of technical details. I know that the very similar AudioTechnica Series 10 wireless kit, which appears to use identical 2.4GHz technology will operate as many as 6-8 microphone transmitter/receiver pairs concurrently. One would assume that the Rode product will also operate at least two concurrent TX/RX pairs. I wrote a comparison between the Audio-Technica System 10 and the RodeLink here:
RODE Announces New Wireless Sytem and Two New Shotgun Mics

The ATW 1800 is a "traditional" analog FM system which uses frequencies subject to takeover by more modern wireless services (cell phones, wireless digital devices, etc. etc.) We have allready seen all our 700 MHz wireless systems made obsolete here in North America, and 600 MHz band is probably next. The RodeLink and AT System 10 use the same 2.4GHz band as WiFi, BlueTooth, and even microwave ovens, so it seems virtually impossible that it will be taken away from us. I have written a summary of the pros and cons of the new 2.4GHz systems here:
https://forums.creativecow.net/readpost/30/874404

[Juha Nurminen]

Thank you for your answer Richard.

To clarify my need for wireless system, I am required to film several conversations of two people on different locations, e.g. both walking down a street while discussing, visiting a store while discussing etc. I think wireless system is best suited for my needs here, as I cannot use a separate boompole holder/audio dude due to both convenience and economics. I could also use them later for filming interviews.

Your comparison matrixes are well thought of. For its chepaness, I am drawn to iphone recording but the fact that I am unable to monitor while recording is a major disadvantage. I also had not thought that the systems using FM frequencies would nowadays have such problems as you pointed out. Not sure what the situation is here in France but the newer 2.4GHz systems do now seem more lucrative. The thing with the "traditional" ATW1800, is that I would only need one receiver, whereas both A-T System 10 and Rode require two separate receivers, thus adding bulk to my setup.

[Donald McPherson]

This is an extremely cheap system. But whether or not you would want to use it is another story.

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[Don Bloom]

I've been using the AT1800 since it came out and honestly, I have never and I mean never had an audio problem. I use Countryman EMW mics instead of the mics that came with the unit, run direct into the camera which is a JVC HM700 for the last few years and prior to that I was using Sony PD series and various DSR series camera and the audio ALWAYS worked.
I am telling you this because in most cases you get what you pay for especially audio gear. I was using another brand of audio gear before the AT1800 and while it worked pretty well the AT has worked GREAT EVERY time without fail. I've done low end, and very high end weddings, corporate type work; interviews, talking heads, seminars, focus groups...you name it and NEVER had a problem with the audio because of the AT equipment.
Buy really good stuff ONCE and it'll outlast your camera gear. Just sayin'.

[Paul R Johnson]

You can buy pretty well anything from the major brands and operate two, one receiver to channel 1 and he other to 2. As long as you use multichannel frequencies suggested by the manufacturers, there won't be issues there. The only issue with radio is that it's prone to RF issues with reflections, or absorption. A piece of wire is cheaper and much, much more reliable. If your shots are outside, the problems get less, but interference is still possible. Critical use means in practice, a skilled person to watch over them. A sole operator has attention on visuals, rarely sound.

The street scene sound fine. The store might be trouble if distances creep up due to the construction and people who soak up RF extremely well.

There are lots of things you can do to help, like getting the receive aerials up high, maybe on a stick poking out of a rucksack, that kind of thing, but if reshoots are possible, then a person with enclosed headphones, listening to the mics who can call a stop is the best way.


Make, in my view are less important. The best are a little better, but still rely on the RF path, and that is 99% of the problem.

[Roger Gunkel]

I would have thought that the cheapest and most reliable method would be a small audio recorders with lav on each of the speakers, then simple synching at the editing stage. Good quality, no worries about loss of RF, no picking up of electrical interference and absolutely no range problems.

Synching is extremely easy in most editing programmers, either with software audio synching, or even manually to the wave form. If using two matching recorders, there should be no drift problems between them and quite easy to correct with audio even if there was.

Roger

[Steve House]

Originally Posted by Roger Gunkel

I would have thought that the cheapest and most reliable method would be a small audio recorders with lav on each of the speakers, then simple synching at the editing stage. Good quality, no worries about loss of RF, no picking up of electrical interference and absolutely no range problems.

Synching is extremely easy in most editing programmers, either with software audio synching, or even manually to the wave form. If using two matching recorders, there should be no drift problems between them and quite easy to correct with audio even if there was.

Roger

The problem with this method is it's impossible to monitor the audio as it's being recorded, a major drawback.

[Don Palomaki]

The AT1800 series offers a 2-channel receiver option allowing two wireless transmitters to communicate with it at the same time. Makes the package at the camcorder a bit smaller.

I've been satisfied with my 1800 systems for both wedding and music work.

[Robert Benda]

Two separate wireless lavs, into a Tascam recorder (left and right), then into your camera. That gets you dual source, and you can still mute one or both. Synching is easy, too, if you even need pull the audio off the recorder.

I'd also have pocket recorders (or, fine, iPhones) available just in case of trouble.

When buying microphones, they will list their frequencies. Cheaper units you won't be able to change it. However, when buying it, you'll still see a listing for its frequency. For instance, my Shure mics are listed for sale like:
H8: 518-542 MHz
J10: 602-620 MHz
K12: 620-638 MHz

So, if I want to buy more than one to use at the same time, I just make sure I buy the unit on a different frequency.

[Roger Gunkel]

Originally Posted by Steve House

The problem with this method is it's impossible to monitor the audio as it's being recorded, a major drawback.

I agree you can't monitor while recording, but to record two people walking and talking it would be very simple to check the audio levels before they start walking as their levels will be pretty constant. I wouldn't see that as a major drawback for that type of recording, but if the money is available for a good quality and reliable dual wireless system then that would be the way to go.

Roger

[Jon Fairhurst]

Monitoring isn't necessarily just about the levels. You want to hear if there was clothing noise, cellphone buzz, a crackling connector, or some background sound that ruins the take.

Of course, you can do this after the shot but listening to the audio after the take for a quality review isn't really done. It breaks the production flow and we don't necessarily want to mess with the equipment to go from recording to finding the right file, playing it back, slogging through dead space, finding that particular take, etc. Personally, I only want to hear it after it's sync'd up and in a comfortable listening space. On the other hand, listening for errors during the take is quite natural.

There's a feature opportunity here. An intelligent "instant review" button with shuttle/jog wheel would be quite cool.

[Roger Gunkel]

Originally Posted by Jon Fairhurst

Monitoring isn't necessarily just about the levels. You want to hear if there was clothing noise, cellphone buzz, a crackling connector, or some background sound that ruins the take.

Of course, you can do this after the shot but listening to the audio after the take for a quality review isn't really done. It breaks the production flow and we don't necessarily want to mess with the equipment to go from recording to finding the right file, playing it back, slogging through dead space, finding that particular take, etc. Personally, I only want to hear it after it's sync'd up and in a comfortable listening space. On the other hand, listening for errors during the take is quite natural.

There's a feature opportunity here. An intelligent "instant review" button with shuttle/jog wheel would be quite cool.

I certainly don't disagree with what you are saying Jon, but I think it is also dependent on the type of filming you are doing. If it is a shoot with the ability to retake, then live monitoring will always win hands down, but a get it or miss it shoot is going to be about taking all the precautions you can to place mics to avoid clothing rustle, turn off phones and pre check the levels. On the latter, I would rather trust a portable recorder than a radio system, but given the opportunity, portable recorders with paralleled wireless for belt and braces.

Roger

[Jon Fairhurst]

Good points, Roger,

For me, I use a wire whenever possible. A $20 cable easily beats a $1,000 wireless system - except when using a wire isn't an option. An on-person recorder, wireless, and remote monitor + backup recorder would give the best of all worlds.

What I find interesting is how easy it is to review video clips immediately after a take and how impractical it is to review audio on the set. And to pack up the equipment without ever hearing the recordings is risky.

Some thoughts on why on-set audio review is tough:
* Only one person generally has headphones. All others stand around during the review, which can be time consuming. (With video, many can gather around the monitor, so they are entertained.)
* Headphones only have so much isolation, so reviewing is tough. Is the jet airplane on the recording or in the sky right now? (Unless there is glare, or the monitor is too small, you can see a video review clearly on-set.)
* Dead space is disconcerting. When listening to near silence, you don't have context for when the meat of the recording will start. (With video, you see the set and actors, so you have faith that the action is coming soon.)
* It's hard to know if the audio you are hearing is from the take of interest. We don't have good audio memory when the lines and delivery are similar. This is especially true if you didn't hear the perspective of the mic during the take. (On the other hand, everybody on set saw the action. We have good visual memory, so it's easy to correlate the replay with the live visual experience.)

Before I had experience shooting, I never would have thought that audio review would be difficult. Now, I find it to be an interesting combination of equipment and human limitations. I never really know what I have until I can hear the audio sync'd with video in a quiet space with monitors. Even with live monitoring, I can only identify obvious problems. It's easy to hear bad quality. It's not so easy to know how close things are to perfection. :)

[Roger Gunkel]

All fascinating stuff Jon and just reinforces how difficult good audio can be. I spent many years recording live music sets as part of my studio engineering time and it is so different engineering in the studio with total isolation, to recording live when the band is in the same room as you, together with the crowd etc. Trying to get a great recorded bass sound through cans when the live sound is bouncing round the room used to be a nightmare.

Many similarities with location video sound, so many ways to get it wrong!

Roger