VOCABULARY FOR THE DAY... • Acoustics – The behavior of sound, and it’s study. • Reverb – A sound effect that simulates different size rooms. Basically, it’s “echo” • Dry – The sound coming from a PA system with no effects (raw sound). • Distortion – usually an undesirable result from overloading the system... please check and make sure your system will not blow up momentarily : ) • Wet – having reverberation or ambience. • Early Reflection – The first echoes in a room, caused by the sound from the sound source reflecting off one surface before reaching the listener. • Wave – a continuous fluctuation in the amplitude of quantity with respect to time. • Wavelength – The length of one complete cycle (peak to peak, trough to trough) • Sound Wave – Short for Sound Pressure Wave (a wave of pressure changes moving away from something that is vibrating between 20 times a second and 20,000 times a second. LETS TALK ABOUT REVERB What is reverb? From our Daily Class Questions we learned that reverb is basically an effect used to simulate a room. It can make you sound like you are in a huge gymnasium, or a tiny practice room. Reverb works wonders for making something sound more full and bigger than it really is… but what is it really changing? SOUND WAVES! Did you know that each and every sound is a real, physical WAVE!? Here’s what some different sounds LOOK like… BACK TO REVERB… So, now that we learned briefly about sound waves, let’s talk about how they travel… Sounds travel in all directions, and if the object making the sound is stationary, at a constant speed. If you were sitting in an empty room listening to music from one speaker, this is what it would look like… REVERB CONTINUED… Notice that there are three different points of contact for the sound in this picture… the “direct signal” and then two “early reflections.” For our discussion, reverb comes from the early reflections. Notice that the path each early reflection takes is longer than the direct signal? This is what causes the delay, or reverb. REVERB CONTINUED SOME MORE… Now that you understand how sound bounces and travels, here’s what that room REALLY looks like… SO HOW DO YOU USE IT ON YOUR MIXER? Here is what a typical sound board (mixer) looks like… EVERY SOUND BOARD IS DIFFERENT, BUT THE SAME… As you can see by looking at the pictures and looking at our synthesizer cart’s sound board, they are VERY different. However, they are also VERY similar. Reverb is usually found in the effects channel on your sound board. You can control how much effects you want in each signal by turning the EFX 1 or EFX 2 knobs left or right. On our synthesizer cart, we have a separate knob specifically for reverb. ENOUGH ABOUT REVERB!!! WHAT ARE THE OTHER GAGILLION KNOBS AND SLIDES FOR!? Every sound board can be broken down into three main parts… the volume, settings, and effects. Let’s talk about the volume first… Most mixers have slides that control the volume. We have mixers that utilize both styles... SETTING EACH CHANNELS VOLUME OUTPUT There are three main areas of volume to be concerned with… first is the individual channel volumes, second is the monitor volume (we will skip for now), and third is the main volume, or “Master Volume.” It’s actually real simple… let’s say that we are running sound for someone who is singing and playing a guitar. You want to adjust the individual volume of each component (voice/guitar) to where it sounds good to you! You will typically want more vocal sound than guitar sound, so you will set your channel volume to the desired level for each channel. Then, you can adjust the main (master) volume to how loud you want your mix to be. THE SETTINGS What are all those knobs for!? Here are your main settings every sound board will have (we will break into detail on each)... Gain/Trim Highs Mids Lows AUX / MON 1 and 2 EFX GAIN/TRIM/LEVEL On most mixers, the very top channel setting will be the GAIN knob. On others, it may be called TRIM or LEVEL, but it all means the same thing. This knob is used to deliver the correct amount of signal the board receives of that particular voice or instrument. It can get extremely complicated using this setting, so here is the basic rule... Make sure all the volume is turned off (muted) on the entire board, each channel AND main volume. Turn the channel you are setting, on. Play the instrument at it’s loudest part and adjust the gain knob up just until the instrument begins to peak, or hit the “red” on the light board. That’s it... Don’t touch the gain knob again! Set it, and forget it! One of the most common mistakes people make is using the gain knob to adjust volume... HIGHS The “Highs” setting controls how much high frequency is placed in the mix. The instrument, voice, or sound you are controlling should determine how much high frequency is put into the mix. For example: A flute would need more highs than a tuba. Setting too much high frequency can be a bad thing, however... You need to use your ear and determine what sounds the best. While there are limits to how you can set it, there is no fine line that determines right from wrong. MIDS The next setting you will have on your channel is MIDS. Depending on the sound board you may have two knobs, High-Mids and Low-Mids, or just one knob that controls all the Mids. The MIDS setting adjusts just what it sounds like... the middle frequencies. Nearly all voices and instruments need some MIDS put into them in order for them to sound natural... again, how much depends on your ear. With the exception of the extremes, there is no right or wrong. LOWS Again, this setting adjusts what it says... the low frequencies of the voice or instrument. How much you put into it depends on your ear. There are a few things to keep in mind with lows, however... A flute does not need much LOWS in it at all... it plays mostly high frequency stuff. A Tuba needs more LOWS in it... it plays mostly low frequency stuff. An instrument that plays the entire spectrum (low-high frequencies) will need some LOWS, MIDS, and HIGHS... but at a roughly balanced level depending on the sound you want to get. AUXILLARY / MONITORS Auxillary, or AUX knobs can be found on most mixers, but not all. These knobs control the amount of OUTPUT sent to their assigned device. For example... My in-ear monitors that I use when drumming are run through the AUX 3 channel on our church’s sound board. If I need more lead guitar in my ears, the sound guy goes to the lead guitar’s channel and turns UP the AUX 3 knob, thus giving me more lead guitar volume in my ears. The most important thing to remember is that the AUX channels are OUTPUT, NOT INPUT. MONITORS work the exact same way the AUXILLARY knobs work... Most boards have a MON 1 and a MON 2 knob which allows for 2 stage monitor mixes. EFFECTS (EFX) Effects, or the EFX knobs, are on most soundboards but not all. Effects can be a bit tricky to deal with so here are the basics of how they work... Most boards have 1-4 EFX knobs. You must first set your effects (more on that later) over on the “effects portion” of your board. Once you have designated a specific effect to an EFX channel (for example you put reverb 24 in EFX 2) you can adjust how much effects you put in each channel. NOTE: On most boards you cannot have different effects for individual channels... for example: On channel 1, EFX 2 is reverb... therefore on channel 2, EFX 2 can only be reverb. You cannot set EFX 2, on channel 2 to anything else. OTHER ODDS AND ENDS... Other buttons your mixer has or may have on it... MUTE button- Mutes everything for that specific channel LINE/MIC button- Adjusts the signal based off of whether you are using a mic cable or a ¼” cable.