The electrical engineers at Pioneer didn’t put red lights in the level meters just because they enjoy the color. It’s there to let you know that your signal is deteriorating. A deteriorating sound signal is like when food goes bad. It stinks and no one should have it forced upon them. “Redlining” is just another term for Clipping.

The Sine Wave

If you’re a DJ you have to be a real schmuck not to have heard of a sine wave. Over on the right here, we see an example of one. Notice how smooth it looks. That’s exactly the kind of signal you want reaching your speakers.

Notice those little tic marks on the Y axis of this graph? Those represent the maximum level that that sine wave can be before it will start to distort.

OK, see that blue, smooth sine wave? That’s what it should look like when your levels are all green, or slightly flirting with the yellow.

Remember those tic marks from the other picture? They are represented on this graph by Vcc (Voltage Cycle Clipped)

Once you crank the gain on your channel, and bring those lights into the red, your signal is no longer a pretty sine wave, it looks like the green section of this wave, because the peaks of the sine wave are sheared off by the clipping limits. What you see with the green part of the wave is a CLIPPED WAVE… and therefore… a distorted signal.

Now it looks like a cross between a sawtooth and a square wave, neither of which you want going to your speakers.

Quick Lesson On Equipment

Let’s explain quickly what equipment is in your chain and what it does, exactly.

Controller/CD-Player/Turntable : All this does is take the sound from the medium you have and convert it to an electrical signal. Some controllers have mixers built in, but for this I’m talking about standalone units. It doesn’t really amplify a signal at all. Even a Technics 1200 doesn’t amplify the tiny signal the needle produces by vibrating in the groove. Assuming your equipment isn’t made at Safeway, what should come out of your unit is a nice clean sine wave.

Mixer : There are several “points of gain” here on a mixer. You can increase the size of the signal with channel gain (of course), with the volume faders, and even with the EQ potentiometers. If any of those settings cause the signal to clip before it gets to the Master Volume knob, your signal will be distorted no matter what setting the Master is at.

That means you need to be conscious of what is happening with your signal at all times. Of course the signal will be smaller before the bass kicks in. Be aware of it. MP3s are also all recorded at different levels, you’ll need to adjust each track a little.

Amplifier : This is pretty simple. All this really does is take the signal from the mixer and amplify it significantly for end use at the speaker. If you put a distorted signal into it, you will get a distorted signal out of it. You CAN actually damage the equipment by running it too hard with a muddy signal.

Speaker: This is the last link in the chain before your eardrums. Again, if it gets a distorted signal, it can actually damage the speakers, not to mention your ears.

How Can I Be a Non – Sucka DJ?

This is actually super easy. There’s a couple things you need to be aware of. Tracks are all produced at different levels, so yes, you will have to make trim adjustments all night, however it should be noted that you’re only adjusting so you can keep a consistent sound, not to make things louder. Do that with your master (if you have to.)

The BEST and most responsible way to keep your sound perfect is to come out from behind the DJ booth and take a listen. Stand in different areas of the room. The sound will be different depending on the shape of the room and what it’s made out of. How many bodies are in it to absorb sound? If you’ve got an early set, there’s no reason to be playing peak hour volume early in the night.

It only takes a second to run out on the floor and in the back and see what it sounds like. Different genres have different sounds. If you’re changing it up, make sure you check and see what it sounds like after you shift gears.

An even easier way is to look at your crowd. If you see them leaning into each other shouting, especially when they are no where NEAR the speakers, then it’s too loud. Dial it back.