I plan to shoot some mountain biking video. I would like to grab some 4 channel audio with an H2n. I'd like to merge that with my video. Obviously I have to do this after the fact since my camera will only record stereo. The questions are;

Will synching the two be a big deal?
The camera has a mic input, should I send the H2n line out into the camera in for an easy reference?
What exactly will the h2n send to the line out while recording in 4 channel mode?

I'm very new at this so please excuse me if I asked something that does not make sense.


Thanks!

I plan to shoot some mountain biking video. I would like to grab some 4 channel audio with an H2n. I'd like to merge that with my video. Obviously I have to do this after the fact since my camera will only record stereo. The questions are;

Will synching the two be a big deal?
The camera has a mic input, should I send the H2n line out into the camera in for an easy reference?
What exactly will the h2n send to the line out while recording in 4 channel mode?

I'm very new at this so please excuse me if I asked something that does not make sense.


Thanks!I'm not sure recording 4-channel in the field makes sense for this sort of project. What are you trying to accomplish by doing so?

Get more atmosphere and positional feel. Its a single track through the woods with bikers in the front and back sometimes. Its an experiment too. When someone passes me it be nice if the sound would reflect that.

Carl,
If I were doing this I would record audio to the camera (2 channels) and use the Zoom to record the other channels for sync in post. the camera will only record so many channels and 2 is it. Left and right.
Like I said sync in post and mix to taste but don't be surprised if you're not a bit disappointed in the quality of the sound. Stuff like this usually has a lot of gear and dedicated audio people working it plus a lot of sounds are added in post-called Foley.
When I did NASCAR, I would watch the audio guys setting up around the track. Ever wonder how TV gets all those sounds around the track? It's because even on a 1 mile track they might have 15 or more mics set up on the fence and that's just for the sounds of the cars. Then add more facing towards the fans to get the crowd noises, mix to taste in the audio truck, send it to the production truck for the feed out and you're done.
You can get some of what you want using what you have but you'll probably have to add some later. It'll be a great learning experience.

I'm not that good at audio. So I am concerned that the sound the camera picks up will be somewhat different feel to it than the H2n's audio. So when I mix them I might have to equalize or somehow change the quality of the sources to match each other while I am mixing them. Seems daunting. I only have Cyberlink PowerDirector with Audio Director.

Anyway, I can do it both ways. It will be interesting. The H2n is a bit expensive for a toy though so in the end I think I will have to make it work.

What camera are you using? If it's a DSLR you might want to give serious consideration to forgoing use of the camera's mics and audio.

Its a POV. Contour +2. But I'm not looking to use the cameras audio. It does not record in surround.

Its a POV. Contour +2. But I'm not looking to use the cameras audio. It does not record in surround.Then the issue of whether the camera audio's tonality matches that from the H2n becomes moot ... you won't be mixing them.

I think Don was suggesting that I record the standard audio with the camera and get the surround audio channels with the H2n. But I don't really know how to do that anyway. The Camera is recording stereo which includes front/back/left/right. Its just that they are all mixed in together. The H2n records the same thing, but it separates them out. so if I mixed the camera audio with the H2n, I wouldn't know which H2n channels to use!?

Again, Im new so my thinking could be completely wrong.

Presently, this is what my first experiment will look like.

H2n in 4 channel mode mounted on apex of helmet with wind screen.
Contour +2 mounted on side of helmet.
Audio out channel of H2n connected to mic input of Contour +2 in order to aid in syncing the audio.


I'm unfortunately assuming a lot. Like I can take these 4 channels, and mix them into a Dolby 4 channel surround format when the channels I have will be front/back/left/right but the channels dolby uses are LF/RF/LR/RR, etc..

"I can take these 4 channels, and mix them into a Dolby 4 channel surround format when the channels I have will be front/back/left/right but the channels dolby uses are LF/RF/LR/RR, etc.. I"
- Only if your NLE/DAW can encode to your desired format

...The Camera is recording stereo which includes front/back/left/right. Its just that they are all mixed in together. The H2n records the same thing, but it separates them out. so if I mixed the camera audio with the H2n, I wouldn't know which H2n channels to use!?

Again, Im new so my thinking could be completely wrong.

Presently, this is what my first experiment will look like.

H2n in 4 channel mode mounted on apex of helmet with wind screen.
Contour +2 mounted on side of helmet.
Audio out channel of H2n connected to mic input of Contour +2 in order to aid in syncing the audio.


I'm unfortunately assuming a lot. Like I can take these 4 channels, and mix them into a Dolby 4 channel surround format when the channels I have will be front/back/left/right but the channels dolby uses are LF/RF/LR/RR, etc..
Stereo is left/right, not left/right/front/back. When you mix a stereo signal to 4-channels stereo 'left' becomes 'LF' (left-front) and right becomes 'RF' (right-front). Dialog is recorded mono and mixed equally into the LF and RF channels in post to make it centred on the screen and makes up the front-center channel of a 5.1 mix.

Plugging your Zoom's output into the camera's mic jack will most likely disconnect the camera's internal mic so you won't be getting any audio from the camera mics themselves. (I can't say for sure because looking in the camera manual it doesn't say but that's usually the way it works.) The resulting stereo track in the camera will be a copy of the stereo output from the Zoom, a scratch track to use as a reference for syncing but NOT a usable stereo track to mix in with the Zoom's tracks. And there's another issue as well that you need to take into account ... the Zoom's output will be line level but the camera input expects mic level, which is much, much lower. Plugging them together requires an attenuating cable else the incoming signal will overload the camera's input, resulting in very high distortion.

Windscreens are designed to reduce the noise of relatively mild air movement, not the gale-force winds passing over the mics from the motion of the mic/recorder through the air while mounted on the head of a bike rider moving at speed. I would expect mounting the recorder on your helmet as you described will produce completely unusable tracks due to the wind and handling noise.

Thanks for the replies. I'm not a professional, just a tinkerer trying to slightly improve his videos. So some flaw is not too bad for me.

The h2n itself records 4 channels. My expectation is to get all 4 channels from the h2n. I'll feed the signal out of the H2n into the video recorder only as a way to sync the h2n's audio to the camera's video. Since the camera's audio and video will be synched, I'm expecting that synching the h2n to the camera's audio will effectively sync it to the video as well. Perhaps this is not necessary since they will be basically next to each other during record? I won't render the camera's audio to the output of the track. Its only for synching. The more I think about this, its probably not necessary. I can just synch it by eye/ear I guess. But having the audio signals next to each other and synching it that way seemed safer.

I'll start a new thread asking about NLE's that can do this. I've searched for a few days looking and haven't come up with much. That is, NLE that can take multiple channel data and mix it into 5.1 output (which will actually just be 4 channel with no center I'm thinking)

First of all, I question what you said about the Zoom's outputs: left, right, front, back. That would be a very unusual track assignment; no playback system is arranged like that. (Well, back in the old days of CBS/Dynaco quadraphonic LPs there was LF, CF, RF, and center rear; but that never caught on anyway.)

I'm pretty sure the zoom will give you a front pair which is LF and RF. And also a rear pair which is LR and RR. If that's the case, you won't need to do any mixing to position the tracks on the correct channels for playback.

I wouldn't bother to connect the Zoom to the camera. They will both be mounted on your helmet, and both will pick up the same sounds at the same time. They'd need to be 30 feet apart before there would be even one video frame of time difference. You will then just sync the Zoom tracks to the camera's scratch tracks.

If I were you, I'd make some test runs with just the Zoom, to see how bad the wind noise will be. I suspect that will be your biggest challenge. You may need some foam plus a fuzzy to try to kill the wind. You'll look as if you're riding down the trail with a dead skunk on your helmet, but hey... maybe nobody will sideswipe you!

You're right. I'm not sure where I got that impression. Its definitely a front MS pair, and a rear XY pair I believe. But even still, won't I sort of mix all 4 into each channel to some degree?

My initial thoughts were that I would take an existing 5.1 track, and replace the audio in the 4 corner channels, leaving the front and .1 empty. But I now think that won't sound right, and so am looking for different mixing software. But a friend has Logic Pro which should work.

I'm pretty sure there will be wind noise. I have made several records with a previous camera which probably has better audio than the zoom. But I also think the fuzzy thing should help quite a bit because mostly I ride in the trees where its not that fast and not that open to breezes.

I'll be doing some test rides around the block to test all the equipment before I take it out for sure.

I'm curious where you found the info that the front pair is M/S. I didn't notice that anywhere in the online manual. And I don't think that's consistent with their claim that the front pair has a 90º mic angle.

At any rate, a mic does not work like a lens. With a lens, a given object either is, or is not, within the lens's field of view. A microphone picks up all the sound around it, in a 360º sphere. Even if it's a "directional" mic, the sound in the desired direction is just louder than the sound in the other directions (and often the frequency response in the desired direction is flatter than in the other directions).

Thus, every channel of your recording will contain sound from a 360º sound field... it will just favor the desired direction. So I doubt that you'll need to do any further mixing... that would just dilute the directionality of what you've captured. Except that if you do have a LF subwoofer, you might want to mix the LF information from all four channels into that .1 LF channel.

mostly I ride in the trees where its not that fast and not that open to breezes
Just the fact that your bike is moving will create "wind speed" equal to your bike's velocity... even on a perfectly still day, even indoors.

Its mid side. That recorder has a mid-side pair in one direction for sure. And an xy in the other. Its all over the documentation. http://www.zoom.co.jp/products/h2n/
I suppose with what you say, I'll have more options for the encoding. Just need to decipher the mid-side in the front direction.

There will be wind but in previous recordings with my camcorder its not bad and I've never used a windshield. Plus this is mountain biking, its slower. Anyway, its all in fun plus if the wind sounds right and is based on bike speed it can add to the ambience.

My mistake, I opened the manual for the H2, and not the H2N.

Even so, I doubt you will need to do any decoding for 4-ch surround.

The manual makes it clear that there are two different recording modes using the M/S capsules. You can record in "Raw M/S" mode, which records the M signal to one track of the final file, and the S signal to the other track. But there is also an "M/S Stereo mode" where the matrix is applied in the recorder, so that the recorded file contains a left-channel track and a right-channel track.

It appears (p.22 step 2) that if you adjust the S mic gain = 0 dB (stereo width = 120º) before recording, then the "M/S" file will still contain normal stereo information, rather than raw M and S information. In that case, you'd just assign the "M/S" stereo track to the two front speakers, and the "X/Y" stereo track to the two rear speakers.

Your biggest issue is not likely to be stereo perspective.

Understand that that's only an issue if you're playing the audio back on a 5.1 theatrical style system - which represents about .5% of the playback situations in the world.

Your work is MUCH more likely to be consumed on stereo (personal playback via earphones) or mono (any phone or small speaker that sums to mono)

Of much more importance is the quality of the recorded sound. If you're recording while in motion - you're going to have to deal with AIR MOVEMENT - no matter what mics or devices you use.

If you don't address that via air movement baffling - your audio will get infected with all sorts of wind noise which is much more critical than stereo perspective.

FWIW.

I am aware of the air movement issue. I have filmed while riding my bike before. Its not that bad. Plus, I plan to add some additional protection so I am expecting things to improve. We will see. Its going to take some work I'm sure, but its not a show stopper. I won't be selling these so I just need to keep the sound below the annoyance level.

Mostly it won't be played on 5.1. I imagine most of the play will be on my tablet showing people a few minutes of some places I have biked. I'll need good sound for that. But also I will play it on my own home AVR where I do have 5.1 and where I will be looking to enjoy the full sound. Or at least learn a thing or two about how its made.

Greg, for 2 channel recording you have the option of doing XY or MS. For MS you can record it raw and tweak the S later, or you can set the S now, and get a basic LR stereo signal recording. So I could in essence, get the MS decoded on the spot. I won't do that though because I have no experience with MS so its not likely I would pick a good setting on the spot. After a few runs I might be better at guessing and after that, I will go with the pre-mixed MS so that I only have to deal with two stereo channels.

But honestly, I don't know. Its all good information for me. The weather is breaking here in Michigan so I should be out there within a month.

Carl,

If you want to end up with good surround sound for playback on your home system, you should record the 4-track surround mode. Set the S width to either 90º or 120º and your front-facing pair (the mics pointed AWAY from the controls) will be a nice normal stereo soundfield. The rear-facing pair (the mics pointed TOWARD the controls) will also be a nice normal stereo soundfield.

Then if you want to create a 2-channel mix for your tablet (UGH! how will a tablet possibly sound good?), just mix the front left + rear left, and mix the front right + rear right.

OK. I will definitely take those settings for a ride.

I believe the H4n is similar to my DR-40 in that it can record stereo M/S or X/Y, not both. There's only one pair of built-in mics, plus inputs for two others. You can either plug in another stereo mic and record whatever kind of stereo you want to the other two channels, or you can plug in two mono mics for the other two channels. That's how my DR-40 works. When I was researching them before I bought the DR-40, the feature set was nearly identical for 4 channel recording.

In any case, you're not going to get M/S and X/Y out of the one pair of built-in mics.

We're talking about the H2n here, (not the H4). It has a total of five mic capsules.

Two are "front facing" which means facing toward the side of the recorder that has the controls. (To my way of thinking, that is facing toward the rear but... oh well.) These are always X/Y.

The other three capsules are "rear facing" which means they face away from the side of the recorder that has the controls. (To my way of thinking, that is facing toward the front but...) One of these capsules faces directly along the front/rear axis of the recorder. It's considered to be the M capsule. The other two apparently face directly left and directly right, and I guess there's some sort of matrix that derives a "S" signal from these.

What's more, there is a switch on the top of the machine that changes what is recorded from the M/S capsules. You can record two raw tracks, one M and one S, for later mixing in post. Or you can have the mixing take place internally, before recording; in that case, you have a choice of 90º spread or 120º spread (presumably obtained by different ratio of S signal to M signal).

And yes, the recorder has a mode that allows you to record four simultaneous audio tracks. The "Front" pair of tracks (which I call rear) is always X/Y. The "Rear" tracks (what I call "front") can be configured as 90º X/Y (or 120º X/Y if you prefer). So yes, the recorder can simultaneously record two sets of stereo tracks, four tracks in all, for LF / RF / LR / RR surround if you like.

Check out the manual, it's available online. Be sure you fine the manual for the H2n, because the original H2 did not have all these capabilities.