3 Ways to Reduce Echo/Reverb on SOUNDTRACK Soundtrack soundtrack

Lately I've been doing a lot of shoots in Open Studio space; Green screen/black drop shoots. This is usually good for all departments since it's a controlled space often meant for this but unfortunately it doesn't seem to help sound as much as it does other departments. Even if air ventilation, compressors, etc are all controllable and/or off, these types of spaces are always so open and hollow, creating an echo which you wont see on screen.

If we were shooting in a cave or an abandoned warehouse, we see it's echoey, so echo wouldn't sound so bad with the image. However, when we see a plain white or black background from a green screen or black drop,  for example, our eyes don't see a "location" so our brain doesn't expect to hear a "location" such as the wide open studio space with hardwood floors, stone walls and 50 foot steel ceilings, especially since these shoots are usually all medium and tight shots. Unfortunately, it's not so easy to take that echoey location sound out of the soundtrack but I do have some tricks.

The good thing about these shoots is that the frame-lines are pretty much always haircuts, so I can get a boom in there real close, not to mention the general simplicity of the entire shoot and shots themselves. BUT, reducing echo on a shoot like this is by far the biggest challenge for sound and I feel like I earn most of my paycheck by doing so. Here are some of my tricks:

1) I use a cardioid shotgun microphone as opposed to a standard supercardioid which I know many mixers and boom ops still use indoors. As long as the environment isn't too noisy (traffic, AC, etc), a cardioid is a great microphone choice with tight shots to help reduce echo due to its pickup pattern. There's is a more dramatic dropoff for anything outside of its range. These microphones are my go to for interviews and small echoey rooms such as kitchens and sometimes large echoey rooms as long as I can get it within 4 feet of the mouth, preferably within 2 feet. The downside other than lack of range is they pickup more background noise since it's less direct. I also like cardioid for improvised conversational shoots since the axis is about twice as forgiving as a supercardioid so if you're a bit late in angling the mic on someone who decides to speak, you're halfway there and if not, it's a smoother transition. Schoeps makes incredible cardioid and omni boom mics such as the mk5 and mk41. Sennheiser also makes a more affordable yet solid cardioid mic best used for interviews, the MKH50.

2) Lav mics generally pick up less echo than shotgun mics, even a cardioid, so I usually have the boom real low in my mix and rely on the lavs. However, not all lavs are the same even if they are omnidirectional. A lot of mixers including myself love the Countryman lav mics, particularly the B6. However, the B6 was not made for interview, green screen, or black drop shoots. I mention its advantages in my earlier post with my review of it, but it's poor for these types of shoots because the B6 picks up the higher frequencies more than most lavs, more than any lav mic I've used. That's bad because when we breakdown the sound of echo, what is it, compared to echoless sound? Echo is produced in hollow reflective rooms. The sound bounces off these walls, windows, glass walls, glass doors, glass ceilings, steal beams, stone, etc which gives us a higher frequencied, quieter reproduction of sounds loud enough to reach the wall and bounce back into the microphone. So, an echo is higher frequency and since the B6 catches that more than most lavs, I like to give my B6s a break on these shoots and use a Countryman B3 which focuses more on the intimate sounding bass in the voice. Also, the Countrymans come with frequency capsules so I always make sure I'm using a flat capsule in echoey locations, as opposed to a +4 or +8db at 15kHz; that's just counterproductive on these shoots. I'm sure there's plenty other good lavs on the market that don't catch echo as much as a B6 or even a B3.

3) The biggest thing I do to help reduce echo on a shoot like this is to build a sound blanket fort. Like I said, the problem with these locations is the reflective walls, the open space, the high reflective ceilings. Things that reduce that echo are as simple as carpet, furniture, people in the room, curtains, and those cheap foamy ceiling blocks you often see in offices and schools. But the thing that I can add to a big open space like this are sound blankets. It's tough since I cant put them behind the talent since it will be in the shot, but I can put it in front of, to the side of, usually beneath and sometimes above the talent. When I can, I coordinate with the DP and Key Grip on where to and building sound blanket walls, ceilings and gaffing down sound blanket rugs. I have a 10 foot long, 10 foot tall green screen stand which I use solely for this purpose. I set that up as a wall and clamp two sound blankets on it, dampening the echo sound and stopping that sound from bouncing back into the mics. When I can, I also set up a blanket above the talent using a 10x10 frame and C-stands with help from everyone's best friend, the Grip department :-). Sometimes flags or a scrim on the 10x are easier though. I surround the microphone with these blankets to prevent the voice from bouncing back into the microphone.

People often think that speaking louder always helps sound. Not always, I'll assure you of that. In a room like this, it likely sounds good, so I can raise the levels higher so they can speak real soft and still sound good on my end. It's when the talent gets excited and speaks loudly, yells, and ends their spiel loudly that hurts us because those are the sounds that are loud enough to reach the glass walls in the way back and the steel ceiling way up there and bounce all the way back. With all this work, it's frustrating because it's still very difficult to reduce echo; it's a lot of work for a minimal effect, although anything we can do, we will.

Now, I'm not a post-guy, but there are some plug-ins that help reduce reverb; keywords "help" and "reduce", not get rid of. One trick I know of and have experimented with is using a noise gate. The reverb that bounces back which we don't want is a lot quieter than the voice which we do want. So, with a noise gate, you can select a db threshold where the echo does not go over, lets say -16db, so anything under -16db, you lower by another 32db perhaps. It also includes an attack and delay to help isolate this effect only to the reverb but it doesn't do much. I've tried this effect and you can only reduce a very small amount of quiet echo before you start seriously messing with the talent's voice which you never want to do. Either way, there are other tricks out there, likely better, but all in all, echo needs to be reduced on location as much as possible and unfortunately even as a sound mixer or sound utility, there is only so much we can do. Be careful when selecting cheap studio spaces for important shoots and please be sure to advise the Sound Mixer of the location beforehand if there is no tech scout. Happy Shooting y'all!

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