Compensating for lousy miking

[Greg Miller]

Adam,

I listened to the clips you sent, and I think you've done a fine job of mixing, compared to the original tracks! The boundary mics sound fine with the orchestra. The only disappointment is that the solo vocalist could stand to be a bit stronger, and that's beyond your control. Adding in the house/camera mics, as you did, adds the chorus, which was largely missing from the boundary track. If the dialog sounds as good as the music, all your efforts were worthwhile. (For some reason, all the tracks seems a bit thin to me... not sure what that represents.)

The final mix sounds much better than I'd expected, based on your pessimistic description. I'm sure the cast and their families will be very happy to have a copy of that.

Of course it's not quite a broadway cast recording. Recording a live performance, with the constraints on miking that you had, makes things pretty tough.

As far as choir mics (or any mics) there are a few considerations, as I'm sure you realize.

I'd start with stereo pair back above the audience, but not too far back. Perhaps hang them out of the ceiling below the FOH lights. I'd use A/B cardioids, spaced a bit (maybe a foot or two) because of the distance, and try to aim them at the playing area. Try to hang them low enough so they'll reach upstage, but of course keep them out of the audience sightlines. With luck those would be your main pair and should get a pretty good mix of all the music. I'd be inclined not to scrimp on these. Of course these do not need to be choir mics, if your head prima donna will allow you to have something more visible.

I have to ponder the closer mics a bit. Choir mics have some advantages, but you have to be careful because they are pointed down at the floor so they pick up a surprising amount of footsteps and other floor noise (sometimes boundary mics are actually better). If I could hang several, overlapping the playing area, I might be tempted to try omnis, because the sound wouldn't change off-axis as the actors move around. I would probably try to use these for dialog, the plan being to keep only one live at any given time, depending on where the stage action is taking place. Think "mono dialog track" as per commercial film/video production. (This presupposes that you can record multi-track and mix down later.) They could hang just upstage of the teaser or borders, depending on where the playing areas are.

Countryman makes choir mics, but I've never been fortunate enough to use them, so I don't know their particular characteristics... of course the company has a good reputation. Shure is a less expensive source. I've had experience with a number of reinforcement systems that use the AudioTechnica mics, and they've been quite satisfactory. Given that these will be primarily dialog mics, these would probably serve you adequately. With this last production, at least, placement was more important than quality of the individual mics, and this video is for "home consumption only," so I think it would be safe to start with these as dialog mics. To put it another way: I think a bunch of these, in the right places, might give better results than a few really good mics in the wrong place.

Of course if money is no object...

No matter how you slice it, you are certainly getting yourself into a major project here. Plan for a lot of time recording rehearsals. And good luck!

[Adam Gold]

Thanks again, Greg! I agree the vocals are thin and I guess that's what happens when your performers are ten feet from the nearest mic. I may add a little more low end EQ and try the 'slightly out of sync' trick to fatten the sound up a bit.

John, if you read back a bit in this thread (as well as any others of mine you might find in this subforum) you'll see that we're exactly on the same page -- I usually tell the same thing to people who contemplate or are advised to try to take a feed from the board. We normally do try to mic the way you've described but most of our attempts have been rejected. Still, thanks for the input, so to speak.

[Greg Miller]

Adam,

As far as thinness, are those tracks flat, or did you happen to roll off the low freqs at all? I would have expected to hear more boominess and fullness from the room (which, of course, might not have been good).

I would use the "slightly out of sync" trick carefully. If your two tracks are a few samples apart, you can create some comb filtering which will do strange things to the frequency response. When you reach 1/30 of a second or so, you will create a perceptible echo which will probably be bad for articulation. Don't overdo it.

[Richard Crowley]

Disclaimer: This is a philosophical response, not a technical one.

Sorry, but if "they don't care" then why should you? You can't push a wet noodle. Call the guy back with the camcorder. I got into video because of the deplorable state of audio for video. And after several decades, I am beginning to understand why it is the way it is. Your story is repeated around the globe, even for higher-end productions where people just don't (or won't) understand what it takes to get good audio. I am turning down productions just because they don't want to do it right and it isn't worth the aggravation to fight with them. In some cases, it took some "tough love" to get their attention about the problems. (Most of which are self-imposed.)

[Jay West]

Originally Posted by Greg Miller

Adam,

As far as thinness, are those tracks flat, or did you happen to roll off the low freqs at all? I would have expected to hear more boominess and fullness from the room (which, of course, might not have been good).

I would use the "slightly out of sync" trick carefully. If your two tracks are a few samples apart, you can create some comb filtering which will do strange things to the frequency response. When you reach 1/30 of a second or so, you will create a perceptible echo which will probably be bad for articulation. Don't overdo it.

Agreed. I was only suggesting this as a quick and dirty stab at fixing the divergence between the sound from the on-stage-mics and that from the mics on or with the cameras in the back of the venue. This divergence will be apparent when displaying the waveforms in PPro's audio tracks. When you have the video tracks synched, the waveforms peaks for the back-of-the-hall mics will be slightly behind those of the front of the hall mics. (Take a zoomed-in-video of somebody speaking on stage and the tracks from the back-of-the=hall mics will be a bit behind the lip movements.) This can be fixed by multi-tracking in an external audio editor, but before going that route, I first try sliding the back-of-the hall tracks to try to get the waveforms to match up better to those of the on-stage mics (such as Adam's boundary mics, in this case). Then, listen. If the sound is now clearer and good enough for what you are working on, you are done. If not -- or if moving the tracks around has just created different problems --- then you take the audio tracks out out to an external audio editor where you can make finer adjustments in a multi-track mix.

[Adam Gold]

Good points all. Premiere has a "chorus" effect that adds a little delay, which might be better than sliding a track by a whole frame. Perhaps there's a way to do this that doesn't make it sound like multiple people. I did in fact add a low-cut filter in EQ to help minimize rumble -- will have to tweak that a bit. Maybe roll it off below 50Hz but boost around 100Hz?

As to why I still do this, as I said above, it's because I can't stand the idea of someone else doing it worse. As long as I still have kids involved in this, I want the DVDs to be watchable. And by doing this I am hoping to expose our business to the many high-end corporate parent-types who are at our fairly-well-off school, but so far no business has come from it. There are a lot of politics involved here as well, but I haven't gone into all the details because they are, quite frankly, really boring and irrelevant to this discussion. But I am indeed this close to punting on the whole thing.

I'm now rethinking the idea of choir mics and miking from above, not only because of the thundering footsteps we'll get from the floor, but because of the potential reflected sound as well. I like the idea of going back to the cards and hypers on stands as they point up and into the air. I can always add reverb but I can't take it out -- I know that much.

[Greg Miller]

Adam, I had suggested choir mics originally as a type of "invisible" mic you could use given the present year's restrictions. Of course they're best for a real choir, because a real choir is standing still.

In any case I think I'd want to have a good stereo pair, located as well as possible. That would probably be on a tall stand 15' or 20' beyond the lip of the stage, back into the house. That would certainly be visually obtrusive, so another option is to hang a pair back there.

As far as solo voices, the best alternative is to nail everyone's shoes to the floor, and place mics appropriately. Once people start moving around, it gets dicey.

If it's a stage play (i.e. not a musical, some mics on stands, in the pit but close to the lip, pointed toward stage action areas, would be ideal.

But if you have an orchestra playing in the pit, that kills the idea of also having dialog mics in the pit. Unless you can have visible mics on visible stands, up on the stage, then you're pretty much back where you were this year. "Invisible" means either choir mics, or boundary mics, (or the rare opportunity to use a plant mic), and each has its own set of problems. Of course the deck should be solid and not too resonant, and actors should wear quiet shoes... but you don't always get that lucky.

Certainly putting mics out in the house, below sightlines, and aiming them past the orchestra will not work.

I'm starting to think that I don't really see "the big picture" concerning future events, maybe that's why I'm waffling around a bit. Anyway, it seems you're over the hump with this year's mix, so congratulations on that score.

[Chad Johnson]

For plays I have shot I can get away with 3 mics (as long as nobody walks out to the audience to deliver lines). I put a Rode NT-4 stereo mic front and center, at the lip of the stage, pointing up abut 45 degrees. Then I put a mic (Rode NT3 or NT55) on each side of the stage, pointing inward about 45 degrees and upward the same. With that kind of setup, and small mic stands the mics are very low profile, but could be made even more so with a black felt blind of some sort between the mic and the audience. But again that's only possible with a reasonable stage manager.

[Adam Gold]

Thanks, guys. This is great info. Rather than drag this thread further off topic I'll post links to my other two threads (in which Chad has already been quite helpful) where we discuss all of this in detail:

http://www.dvinfo.net/forum/all-thin...-zoom-h4n.html

http://www.dvinfo.net/forum/all-thin...-opinions.html

I played around with the existing tracks a little more and the Chorus effect didn't help much and just made it sound weird, which I'm sure is no surprise to you. So I went back to EQ and created a smooth +10 dB, 2 octave hump around 275 Hz and that seemed to help the voices sound a bit fuller, but also made things sound a little dull. So I built another smooth peak around 6600 Hz and that added back a bit of sparkle. The Premiere EQ panel is cool for this as you can just drag stuff around until it sounds right, or at least "righter." The effect is subtle but seems to be a bit better. As Greg noted, this will never be an OBC CD.

So I'm going to call it good at this point, wash my hands and walk away. You can go crazy tweaking this stuff. I'm burning a test BD now to see how it actually looks and sounds on an HDTV/HT with decent but not great speakers.