By Fred Wilharm
As pointed out in my article, “Required reading- Before you Make a Christian Movie”, production sound is almost more important than a great image. If your image is a bit noisy or the whites are blown out, the average viewer won’t even notice. But if the sound is lousy and the dialogue is hard to make out, the general perception will be, “bad movie”. Never underestimate the importance of good production sound.
Even on the very first feature I shot in 1999, I understood this. I had a long way to go cinematography wise, but the sound in the film was not too bad. I was an audiophile and had a collection of mics, mixers and other equipment that I put to good use. Even without a book or website to guide me, I instinctively knew the number one requirement for good production sound: getting the mic as close as possible to the subject. They were hidden in plants, under clothing and other places- but they were CLOSE.
So here are the two go most important rules of production sound: 1) Use the proper mic for the job, 2) make sure the mic is never more than 24″ from the actor’s mouth (99% of the time, this rules out the one camera mic, which is usually too low of quality anyway). These also happen to be the two most broken rules in low budget filmmaking (I know, I’ve broken them a few times myself). So I’m going to go into some detail here to help you understand why these two things are so important.
Sound travels in a straight line. Pristine sound happens when the correct mic is placed the correct distance from the actor at the correct angle. If you have that, the only things that can screw sound up is ambient noise or reflected sound. So two other things you need to pay attention to are other sources of noise in the location, and the acoustic characteristics of the location itself.
Ambient noise in an interior location is simple. There are only a few possible sources of noise – those caused by people and those caused by machines. So if you are shooting in an office building, you will need to shoot at a time when only you and your actors and crew are there to prevent the noises of a functioning office from intruding. In a house, you’ll have more problems with machinery noise. The primary culprit will be refrigeration equipment, whether it be an air conditioning unit or an actual fridge in a kitchen. You absolutely MUST remember to turn them off when recording dialogue. If you don’t, you will be faced with the difference in sound on various takes as the unit cycles on and off.
The acoustics of the inside location are very important. A room with hardwood floors, drywall ceilings and no upholstered furniture can be a nightmare of echo-ness (is that a word?) A carpeted room with overstuffed furniture and a “popcorn” ceiling can make a good recording environment. If your room if more like the first example, some moving blankets and throw rugs can help make it more like the second. Killing the sound from bouncing around the room in this way is one of the easiest, cheapest ways to improve your soundtrack.
Shooting outside can be a nightmare at times. While shooting “Flowers for Fannie”, we encountered all types of outdoor noise. Usually we shot on weekends , and it was late summer in a residential neighborhood. Lawn mowers for miles around cranked up and we had absolutely no control. Shooting “downtown” in our small town was equally problematic- loud four wheel drivers and motorcyclists would see us on the sidewalk shooting and proceed to circle the block to see what was going on. All we could do was patiently wait until the noise source died down.
But there was one source of noise that never went away. During the first several weeks of shooting, our section of Tennessee was invaded by a variety of locust called the “Cicada”. It sounds much like a tree frog and at times the sound was loud enough to drown out normal conversation. SInce we couldn’t “wait out” this source of noise, all we could do was get the mics so close that the noise was as far in the background as possible. We ended up incorporating the sound of the bugs into the “soundscape” of the film rather than trying to completely eliminate the sound, and it actually added to the overall ambience of the soundtrack.
What types of microphones are used for dialogue? Depends on whether you are outside or inside. When outside, you will need a “shotgun” mic mounted on the end of a boom pole, handled by a skilled person. The mic must be mounted in a “shock mount” so that the noise generated by the operator’s hands on the pole are not transmitted along with the dialogue. You can expect to spend several hundred dollars on a shotgun mic. About the only way around that is to find an older, obscure model mic on Ebay (such as the Sony C74 or 76) that was once used in TV production. These can be great mics, but they are heavy and hard to swing around on a boom pole.
Current model shotgun mics that are good and affordable include the highly regarded Rode “NT” models, and the AT 4073. I have used the AT for my last two features, and have been very pleased with the sound. It has a “low cut” switch that when engaged, can almost eliminate boom handling noise issues, as long as the operator has a certain skill level. It’s other great attribute is that it is one of the most sensitive mics on the market, bar none. This not only means it has a lot of “reach”, but that it can record sound at a certain db level at using a low setting on your camcorder’s level control. A less sensitive mic will require that level control to be turned higher, resulting in more noise from the camera preamps. With certain less sensitive mics it’s a losing game – too much preamp noise for useable production dialogue. The only alternative is an external mixer/ preamp, and that usually requires hiring a sound mixer.
Bringing a professional sound mixer onboard is a great idea if you can possibly swing it budget wise. This will allow you to focus your concentration of the image and other aspects of the production as opposed to audio. But oftentimes, budget limitations do not allow this. That’s why I’m concentrating here on the most simple and inexpensive ways to get respectable quality production dialogue with just a boom op.
With this setup, it’s going to be up to you to get the sound levels right. The way to do that is to run the audio from the one mic into both channels of your camcorder. Run one channel at optimum level (just short of peaking). Run the other channel several DB lower. In post, whenever you get serious peaking, you will go to the second channel for usable audio. You’ll find it doesn’t happen very often, but when it does, you’ll be thankful for the alternative channel.
One camera setting that will help insure usable audio is the limiter function. Not all camcorders have this feature and not all behave the same, but if yours has a limiting function that can “clamp” the very worst audio peaks without affecting the audio otherwise, it can be very useful. I usually have this feature engaged at all times.
Monitoring your audio if of course extremely important. Using a long headphone cable or wireless remote transmitter, get some quality headphones on your boom op (Sony 7506 are legendary). Only try to monitor sound yourself on extremely simple shoots.
Shotgun mics are best for exteriors, so what works for inside? The “hypercardiod” is the mic of choice. It’s an extremely directional mic that does not tend to record too much of the reflected sounds bouncing off the walls and ceiling. A shotgun used in an echo prone acoustic environment will tend to pick up the echo more readily, giving your sound that “hollowness” you hear so often in low budget flicks. I use an AT 4053a (the new model has the “b” designation) because it sounds just like the 4073 I use outside, and has the same useful low cut switch. If you can’t afford the $600 or so it costs, consider the Oktava MC-012. This is a Russian mic designed to emulate a much more expensive brand. It also amplifies handling noise, so be prepared for that issue- but the sound it produces is exemplary. Do your research before buying one as fakes are everywhere.
So there it is, the quick and dirty version of how to get great production sound. Use the right mic, get it as close as possible to the subject, (usually booming down instead of up), keep ambient noise under control, and monitor with good headphones. In a future installment I’ll talk about wireless lavalier mics and a few other things that will help you get that crisp dialogue.
What is your mic of choice? Any helpful sound advice you have to share?