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My camera has only one stereo mic input, but I want to use 2 mics

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Jessica Mathies
My camera has only one stereo mic input, but I want to use 2 mics
on Aug 18, 2010 at 6:11:08 pm


I have a Canon VIXIA HF S100 Camcorder, which has only one stereo mic input. I'm going to be doing a lot of interviews, panel discussions, etc. I would like to record two people at once - ideally, I would like to record them to two separate channels, but if that significantly increase the cost, I would settle for both speakers being recorded to one channel.

What is the best way of doing this? I'd prefer not to use clip on mics that plug directly into the camera; wireless is definitely preferred. BTW, these will be low budget videos. I'm not looking for the most expensive brand.

Thank you for any help you can offer me.


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John Fishback
Re: My camera has only one stereo mic input, but I want to use 2 mics
on Aug 18, 2010 at 6:53:38 pm

You may be better off hiring an audio pro the first time to see how it's done. Basically you need 2 wireless mics and receivers, and a mixer to control the levels and direct the signal to the left and right channels of the camera (and cables, adaptors, etc.) Doing that properly with reasonably priced gear (not bottom-basement junk) will cost in the neighborhood of $3,000. If you'll be doing this kind of shoot a lot, then it's a reasonable investment.


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Jean-Christophe Boulay
Re: My camera has only one stereo mic input, but I want to use 2 mics
on Aug 18, 2010 at 6:56:34 pm

Hi Jessica,

To plug two mics into that camera, you'll need an adapter cable which breaks out to two female XLR plugs, which will each be plugged into its own mic. Basically, something like this only with female XLR connectors. This may be a bit hard to track down, as it's not a common audio connection at all.

As for mics, I'm from the cozy studio side of things so people on here with more location experience can surely guide you better on that. With this kind of setup you'll need mics with receivers on which you can control the output level, as you won't have a mixer before the recorder and need that control.

With this kind of setup, each mic will go to its own track of the stereo feed the camera records. One mic will be on the left track, the other on the right track. As that camera records directly to stereo AC3, from what I've seen, you'll have to convert the audio before editing and mixing it back into a stereo mix. A simple mix will be needed, as I'm sure you want both voices to come out of both speakers on the end product.

John does have a point about hiring an audio person, though...


JC Boulay
Technical Director
Audio Z
Montreal, Canada

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Sam Mallery
Re: My camera has only one stereo mic input, but I want to use 2 mics
on Aug 18, 2010 at 8:32:06 pm

Don't use a Y-cable to plug two microphones into a single stereo mini-plug input. 99% of the time this results in unusable sound quality.

The cheapest way to plug two mini-plug microphones into a single mini-plug input is with the Azden CAM-3 (it sells for around $45):

This tiny plastic mixer will actually allow you to plug up to 3 mics into your mini-plug input. You must keep in mind that this is the hand's down cheapest way to do this, and you get what you pay for. The better way to do this is with a Camcorder XLR Adapter box (such as a Beachtek or a juicedLink). I'll explain this later in the post.

In keeping with the theme of doing everything as cheaply as possible, if you decide to go with the CAM-3, the cheapest wireless lavs that I would recommend are the Audio Technica Pro 88W systems. You would need to buy two of these (they sell for around $150 each):

Each of your on-camera subjects would wear a clip-on mic and a transmitter beltpack. You need to mount the two Audio Technica wireless receivers and the CAM-3 mixer on your camera. You need to plug headphones into the headphone output of your camera to make sure everything sounds right when you're shooting.

If you want to do this right, you should get a Beachtek or a juicedLink box. These boxes mount to the base of your camera and have a little wire that plugs into the mini-plug input on your camera. The box has two XLR inputs for better quality mics.

A much better pair of wireless systems to buy would be Sennheiser ew 112-p G3 (they sell for around $600 each):

Again, you would need to buy two of those systems.

If you can't afford the Sennheisers and you want to go with the Audio Technica Pro 88W systems and a Beachtek or juicedLink box, then you should get special XLR output cables for the Pro 88W. This way you can plug into the Beachtek with XLR connectors. The speical cables you need to do this are Audio Technica CP8306 Adapter Cables. They sell for around $15 each.

And of course, if you hire an expereinced location sound person, you won't have to buy any of this stuff or even have to think about audio when you do your shoots.

Every night I wish I could hire an experienced French chef to cook me dinner.

If you can't afford to hire a pro, then you need to invest in this equipment to do what you want to do. If you go this route, you need to practice a lot with this equipment to get used to using it. Once you are comfortable with the gear, then you can start doing your shoots. Never get too comfortable with audio gear. You need to constantly monitor it with headphones during the shoot to make sure it sounds good.

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Richard Crowley
Re: My camera has only one stereo mic input, but I want to use 2 mics
on Aug 19, 2010 at 5:34:34 am

Stay FAR away from cheap wireless mic systems. Anything less than $500 is a throw-away, fiddly, unreliable plastic toy and a total waste of $$$. I can't say that I would recommend that little plastic Azden "mixer" to anyone, either. Adzen earned its poor reputation the hard way.

Unless your interviews and panel discussions are with marathon runners out on the road, not clear why you need wireless systems on such a low budget? You gotta walk before you can run (pun was not intentional.)

Probably the absolute lowest-price lav that is worth fooling with is the Audio Technica ATR-3350 (~$20 each). The ATR3550 comes with 3.5mm mini-phone plug that would actually work directly into your camcorder mic input jack, but one mic/one channel only, of course. If you wanted absolutely bare-bones, you could get an adapter that would let you plug two of these into your stereo mic input: Audiogear ADPT2MMFMSM Note that running unbalanced 3.5mm mic cables for very far is fraught with potential problems. If it works, you've gotten away with saving some significant $$$. But if not, it may have been the wiser choice to go with higher-end equipment. Note that some people (myself included) put XLR connectors on these cheap mics almost as "disposable" spares, etc.

A more conventional low(er)-cost lav mic selection would be something like the Audio-Technica AT831R (more like $200 each) which comes with a conventional XLR output connector.

I make my own XLR to 3.5mm mic adapters ( but if you aren't handy with a soldering iron, at the very least get something like this: to allow plugging two separate standard XLR mics (or other audio sources) into your camcorder stereo mini-phone mic input. This would handle any standard professional microphone or audio source that uses the industry-standard XLR connectors.

Note that the audio recording capabilities of a small consumer camcorder are no prize. The mic preamps aren't all that quiet. But worse, you are usually having to put up with the pumping "auto-level" feature. That is why many people would rather spend $200 and buy a separate little sound recorder (with real XLR inputs, etc.) than have to deal with camcorder (or DSLR) "audio".

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Peter Groom
Re: My camera has only one stereo mic input, but I want to use 2 mics
on Aug 19, 2010 at 10:41:21 am

Theres a whole load of info to go on there, all with associated costs. My only advice (so as not to irritatingly repeat what everyone else has said) is for heavens sake, what ever way you decide to go - beachtek, radios, splitter cables (not advisable) etc etc
1) Test and test again
2) Dont plug into any mains. With unbalabnced cables likely around you will get hum.
3) Work out your levels and ceilings carefully
4) Wear, and listen to everything through headphones so you hear problems the instant they arise.
5) Check back recordings at that time. Dont get caught in the "it sounded ok at the time" trap we read about here every week.

But Im afraid my advice has to be, having looked at the camera online, that its audio capability is likely to be low, if its interface is anything to go by. I bet AGC's cant be disabled and are horrid, and the 3.5mm jack makes me shudder. Its a toy!
I suggest hiring / shooting on a more pro end camera and hiring an audio pro to get the sound right for you.
It all depends on how important your project is really!

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Ty Ford
Re: My camera has only one stereo mic input, but I want to use 2 mics
on Aug 19, 2010 at 1:31:24 pm

Hello Jessica and welcome to the Cow Audio Forum.

Great info from our top five audio pros for you. Good audio is not impossibly difficult, but, as you may have discerned from these very helpful posts, it's a craft that requires some knowledge.

I think each of the five who posted will agree that they learn something new every time they do a job. I know I do. So begin now and join us in continuing to learn.

If this video is very important to you, as suggested, hire a competent sound person and ask a lot of questions. Find an affable one who enjoys talking about the craft. Some sound folks are sort of introverted and don't like to talk about anything. Others may buzz around the set causing distractions. One word of caution. I have talked with some folks who tell stories about people who SAID they were sound guys who were not experienced enough and the audio suffered as a result.

I know competent sound guys in many US cities. If you want to go this way, let me know where the shoot is and I might be able to help.

The point about the technical aspects of the audio section of your camera is IMPORTANT. I don't know the specific camera you're using, but if the audio really is important, the best thing may be to double record to a separate device. You probably have enough on your plate right now. It may be to soon for you to fly solo. Get the gear and play with it on your own time. Learn the system. Then use it for shoots.

And a big THANK YOU to everyone who gave you such good advice.


Ty Ford

Want better production audio?: Ty Ford's Audio Bootcamp Field Guide

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Jessica Mathies
Re: My camera has only one stereo mic input, but I want to use 2 mics
on Aug 20, 2010 at 8:27:37 pm

To: John, JC, Sam, Richard, Peter, and Ty,

The CreativeCow forums never cease to amaze me. I honestly don't know what I would do without you guys. Thank you all for taking the time to offer your wisdom and suggestions. I sincerely appreciate your thorough explanations as I am obviously not an expert. Since you all provided me with such detailed information, I'm going to have to weigh out the pros and cons and decide what is best for my audio quality and my pocketbook.

You guys rock! Seriously.

Thanks again,



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Craig Alan
Re: My camera has only one stereo mic input, but I want to use 2 mics
on Aug 23, 2010 at 1:57:58 am


Great advice here. I learn all the time from these folk. Here is some more to chew on, some of it already covered.

Acceptable sound acquisition is way more difficult on limited budgets than acceptable image quality. And for the type of shoots you plan, it is way more important.

A $150 handheld wired mike, a price point that is used by many professional ENG teams, has WAY better sound than a $600 wireless lav kit. The Audio-Technica AT831R Richard mentioned is another wired solid option. This mike requires phantom power so be sure you either get the option with battery power or have gear that provides it.

I know the lavs look better on cam. To get good audio with wireless lavs requires $1200, at least, just for the two lav kits, and trial and error and experience to get them working well. All that said, we use those kits all the time.

Here’s some more links --

2 of these:

Or 2 of these (which gives you the option of a wireless handheld mike with included plug in transmitter (a really great tool for run and gun style interviews. No need to wire the subject up with the lav mic and transmitter (more tricky than it sounds):

1 of these:

1 of these

1 of these:

1 of these: (I use these if I am not using an audio adapter because it allows me to take the strain off the mini-port of the cam mic input. I loop it and Velcro it down and then attach the xlr cable from the mixer to it. Some cams would be better served with a right angle plug on the cam end. But sometimes this gets in the way of other inputs ports)

2 of these: (whatever length you need. Good way to connect mixer to cam or wired mikes to cam)

Ty does not recommend XLR adapters and he knows his stuff. But if you really can’t afford the 302 mixer (which is a great investment at a surprisingly affordable price) you can get by with one of these:

Whatever you decide, as mentioned above, run a lot of tests before the shoot.

And no matter how much you pre-test, monitor the sound with a good set of headphones.

Even if you cannot afford to hire a pro sound guy (your best bet) try to recruit someone to work the mixer, riding the gain controls to adjust for speakers talking at different volumes. One huge advantage of the 302 mixer is (from the manual):
Attenuation is set from 0 to 16 dB in 2 dB increments, and 40 to 56 dB in 2 dB increments. The common attenuation levels of -10 dB (Aux level), -40 dB (hot Mic-level), and -56 dB (low Mic-level) are available.

This means you can fine time the signal from the mixer to the camera to be set at a level the camera likes. This is a huge variable. If you get it right and then ride the levels during the shoot you will have very nice sound, something that really differentiates a pro recording from the truly annoying.

During the shoot monitor with headphones from the camera’s headphone port not the mixers. The Sony one above is an industry standard and you can use it in post for dialog, though listen with studio monitors before deciding on a final mix.

If you want to connect headphones to the Canon HF S100, the camcorder's AV-output doubles as a headphone jack. (You have to go into the menus to select whether the port will output to AV or to headphones). If you're using headphones to monitor sound, you can also go into the menus to activate a test tone for audio calibration.
In the HF S100 menu you'll find a number of other audio features including a windscreen for blocking out the rustle of heavy winds, and a microphone attenuator for limiting audio levels to a specific peak. The camcorder also has a hot accessory shoe that works with Canon's proprietary "mini-fit" accessories.
One more thing to consider is that good audio gear will be solid investments. Camera technology seems to be changing by the minute. But audio gear, though new developments do come along, are much more constant.

OSX 10.5.7; MAC Book PRO (EARLY 2008); Camcorders: Sony Z7U, Canon HV30, Sony vx2000/PD170, Canon xl2; Pana, Sony, and Canon consumer cams; FCP certified; write professionally for a variety of media; teach video production in L.A.

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steven childs
Re: My camera has only one stereo mic input, but I want to use 2 mics
on Aug 23, 2010 at 11:41:01 pm

Something like this might work for you:

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