Sound Operation Hints

Only time, training, and experience will bring about a skilled sound operator. To help get you off on the right foot, let's discuss a few basic operating procedures.

Figure 1
Flex the microphone cables to find intermittent connections.

 

Check It Out

The first procedure, and one of the most important, is to make sure the system is working. That may seem rather obvious, but the time you don't check out the system before the program starts is going to be the time it fails.

Checking the system means just that. You need to check every microphone, cable, and piece of equipment you will need. If you have monitor speakers, make sure they are set at the right volume. It's also wise to gently flex the microphone cables to find intermittent connections (Fig.1). Also, do you have a fresh battery in each wireless. Check the battery, too. Just because it is in a new package doesn't mean it will work. Again, check everything that will be used for that event. Yes, it will take some time. You will have to arrive early enough to get the job done. However, that is one of those thankless but necessary responsibilities that comes with being a responsible sound operator. With time, you will develop your own check-out procedures. Try starting with the basic checklist.

BASIC CHECKLIST

1. Turn On System Are the power indicators lit? 2. Do A Preliminary System Check Do you hear sound? Any unwanted noises? System distortion free? Sound natural/normal? 3. What Microphones are Needed for the Event? Types and quantity Location 4. Check Out Wired Microphones Test Flex cables for intermittent problems 5. Check Out Wireless Microphones Battery good? Microphone cable/connector 6. Set Preliminary Microphone Volume 7. Need Monitor System? Position monitor(s) Plug in and check Set preliminary level 8. Need to Record Event? Confirm blank tape on hand Check signal to record deck Check proper record levels

Feedback Solutions

Now for some operating hints. Let's first talk about feedback. Feedback is a sound term for that terrible squeal, howl, loud tone, or noise when the microphone volume control is turned up too loud. We won't go into detail about what feedback is, but there are some operating methods which will minimize feedback problems.

First, turn on only the microphones that are actually being used. Used means someone is talking or singing into a microphone (Fig.2). In sound systems, less is better. This means you may need to actually operate the mixer controls. Or, you may want to use microphones with switches. However, switches are often forgotten on or off. A good alternative is to use an automatic mixer. An automatic mixer will turn on the microphone when a talker speaks into it. No more forgotten switches!

A fast solution to feedback is to move the talker or singer closer to the microphone. Because the talker is closer, the microphone will receive a stronger signal. Then, the mixer volume control can be turned down and the feedback will go away. You don't want the talker or singer to back away from the microphone. Moving further from the microphone will only make the problem worse, since you already can't get enough volume without feedback. Also, the talker should not cover up the microphone with their hand if feedback occurs. Covering the microphone usually makes the feedback worse.

At the lectern microphone...

while wearing a wireless microphone.

Figure 3
Only one microphone should be on for the best sound.

 

 

Figure 4
The Lavalier microphone needs to be positioned correctly.

 

How Many Microphones?

Another operating hint for good sound is to have only one microphone on for each talker. For example, the lecturer is wearing a wireless lavalier microphone. He walks from the chalk board to the lectern, which also has a microphone (Fig. 3). If both the lectern and the lavalier microphones are on, the resultant sound can be very unnatural. Only one microphone should be used. In a situation where the lecturer is walking from the chalkboard to the podium the lavalier should be the primary microphone. It will provide the least variance in volume as the talker moves around. It should be worn in the center of the body, and about six inches from the mouth (Fig. 4). That will provide the most consistent level with the most volume before feedback occurs. The microphone will produce the best sound if it is placed outside any clothing. It is also good to put a small loop in the cable to reduce cable-movement noise into the lavalier microphone (Fig. 5).

Figure 5
Loop cable back through tie bar to reduce cable noise.

 

Volume Control

One of the great challenges any sound operator faces is setting the right volume for every listener. There is no easy formula. Every auditorium or room will be a little different because of size, acoustics, and the environmental noise. Now add listener age, hearing loss, and personal preference into the formula. About all you can do is experiment and see what level is right for your situation. You must have the level loud enough to hear clearly above the ambient noise in the room. But too loud will be distracting to some people. The right level will probably be when people don't complain. A sound operator will know the volume is right when the sound system is not noticed.

Another side note about hearing loss. Usually, more volume is not the answer to overcoming hearing difficulties in a room. Because of the acoustics and the ambient noise, people with hearing loss are much better served with an hearing assistance system. This will provide the clarity and volume needed to enjoy the lecture or concert.

These operational hints and guidelines will help improve the sound of your system, especially if some of these principles have been violated in the past. Please call your local contractor if you have any questions or comments. If an automatic mixer or an hearing assistance system is of interest, don't hesitate to call your local contractor for more information. They are there to help you. Please call today!

by Ron Huisinga © 1996 Internet Sound Institute (www.soundinstitute.com). This article is for personal use only. Any commercial reproduction is not permitted without permission. To obtain permission, contact ISI at hopi@soundinstitute.com

< Back