How I learned sound engineering

I started learning how to operate perfessional sound equipment shortly before becoming 16 years old.That's when I became the recording enginneer at the First Unitarian Church of Dallas. I recorded all the Sunday services and other events. At first we had a Knight mixing console, but during the first summer, we replaced it with a Bogen MXMA. We had three microphone inputs for the stage, another on the balcony to pickup the piano and organ, and another microphone in the control room. We also built a control panel to be able to playback stereo music from a tape machine or turntable.

We recorded the service on two tape machines. One was a Magnecord and was to record the copies we loaned out and the other was a Roberts, which we recorded the master copies on. The tapes we used were an hour and a half long in order to cover services which were longer than the usual hour. Because I was helping out with the recording, they let me use the equipment for my own productions.

After that, I started doing sound engineering for bands. I was the person who operated the mixing console (also called the sound board to distinguish it from the lighting board). The mixing console feeds the slave amplifiers by the stage that drive the speakers.

Now I guess I should talk about how professional sound equipment differs from consumer sound equipment. The differance is that professional sound equipment has low impedance inputs and outputs that consists of three wires, the ground and two signal wires. The two signal wires are 180 degrees out of phase, so any noise that gets into one wire will get into the other and since the two wires are out of phase, the noise gets cancelled out. Consumer sound equipment (such as home stereos and the sound systems bands used to use) uses high impedance inputs and outputs that only uses one signal wire and one ground. The disadvantage of this is that the cables are limited to 20 feet in length because any longer and you start to lose high frequency response.

I also should point out that there are several different types of mixing consoles. There is the monophonic type like the Bogen MXMA and many of the Shure mixers, which have four or five inputs and doesn't have equalization for each channel. These are manily used for voice, but I've used them for music at remote broatcasts. Because of the high sound pressure levels involved, they usually have to be modified before you can use them for rock and roll.

For recording and for large auditoriums, mixing consoles have to be much more complicated than the ones we used in the church. This was also true for the sound systems used for rock and roll, once it progressed from a teenage medium to mainstream, which happened in the mid-sixties. In the beginning, most sound systems for rock and roll usually had no more than four high impediance inputs and were rarely more than 100 watts RMS. This might have been OK for small night clubs and high school dances, but didn't hack it at all for the larger crowds that started happening in the Haight-Ashbury in the mid-sixties.

For one thing, many of these concerts were outdoors and the small night club PA systems couldn't handle that at all. Nor could they compete with the bigger guitar amplifiers that bands were now using. Another problem was the high impedance systems dictated how long the microphone lines could be, and 20 feet per microphone was not nearly long enough now that stages were becoming bigger and bigger.

It was only a matter of time before somebody who knew something about professional sound systems connected up with the San Francisco rock and roll bands. That person happened to be Owsley, who later became famous for his LSD. The first improvement was using the Altec Lansing Voice of the Theater® cabnets. Although these speaker cabnets didn't have very good bass response, they could project vocals like nothing anyone had ever used before.

It wasn't long before the sound systems were required to carry more than vocals, however. The bigger guitar amplifiers were also making the drums hard to hear. So the drums had to be miked. That meant that the mixers had to have more than the usual four channels. It also meant they had to be low impedance so that longer microphone lines could be used, and the mixing console could be set up where the person operating it could hear the mix. With the extra inputs, setting it and forgetting it was no longer an option.

There was one last problem that had to be worked out. The inputs in professional mixing consoles were too sensitive for the high sound pressure levels common in rock and roll music. This caused all sorts of clipping distortion in the preamp section of the mixer. The solution turned out to be to go to the electronics store and get some trimmer pots (pots adjusted with a screwdriver rather than a knob) and put them across the inputs to attenuate the input level to that which the preamp could handle. To this day, these controls are called trimmers on most mixing controls, even though they are no longer screwdriver adjustments.

The type of mixing console most bands use today are usually stereo and do have EQ for each channel. Finally, there's a third type of mixing console that radio stations use, that have the ability to monitor sound sources before putting them on the air. Few of these consoles have EQ, since most of the recordings radio stations air have already been equalized in the production room. The UREI type we used at KCHU had four microphone inputs, three tutntable inputs and three inputs for studio tape machines, cart players and other sourses, like the EBS encoder and the remote broadcast lines.

The studio tape machines differed from the consumer tape machines in the following ways. First of all, they could handle 10 inch reels. They were two track rather than four, which meant that the tapes were one-sided. They had to be in those days, because in order to edit, you had to physically cut and splice the tape, and if you had something recorded on the other side, the editing would mess it up. Today, we edit everything electroincally, right on the computer screen, so the tape never has to be cut. No tape ever winds up on the cutting room floor, so that saves a lot of tape. Of course, with digital recording, tape is being used less and less.

The cart machines that radio stations use record on endless loop tape cartridges, which were the same as the four track cartridges they had for car stereos before the eight track cartridges. The differance in the two types of cartridges were the 8 track cartridges had the pressure roller as part of the cart and were hermetically sealed, while the studio carts could be taken apart and the pressure roller was part of the cart machine. The studio carts had three tracks and ran at 7 1/2 ips. They were used for recording the commercials and show promos. Their maximum length was 10 minutes. In addition to the stereo tracks, they had a third track called a cue track. The tapes ran until they encounter a signal on the cue track and then they would stop.

So much for the equipment, I really need to talk about the job itself. Sound engineering is both an art and a science. Besides the equipment, which is the science side of things, you have to learn how to use the equipment artistically. You have to learn how to get a good sound pickup and you have to know how to mix the sounds together to get a good mix. Recording rock and roll is a completely different ball game than recording other music. Rock and roll requires close micing. The microphine has to be within a foot of the instrument. The recording engineer who recorded the Grateful Dead Two from the Vault album didn't know that and the recording was botched. It took 20 years before technology was developed that could unbotch the recording.

When KCHU did their first remote broadcast, the station didn't have any microphone stands yet. We were broadcasting a jazz band and what I had to do was hang three microphones from the ceiling, and I was able to get an excellant pickup. There's no way I could have done that with a rock and roll band.

The biggest pain in this business is dealing with the club owners and the talent. The problem with the club owners is they will hardly ever let you set up your equipment the way you need it and the talent blames everything that goes wrong on you, even when it's their fault. The usual problems is they shout too loud in the microphones or they are playing so loud that there's no way to get the vocals loud enough. Life is easier in the studio, since when things don't work out, you can always do another take.

Copyright © 2001, Colin Pringle