Samson MPL 1502 manual Using Equalization

Page 21

Using Equalization

One of the most exciting aspects of using a mixer such as the MPL 1502 is the ability to shape a sound, using a process called equalization. But there are few areas of sound engineering more misunderstood than equalization, and, just as good EQ can really help a sound, bad EQ can really hurt it, so read on...

Every naturally occurring sound consists of a broad range of pitches, or frequencies, combined together in a unique way. This blend is what gives every sound its distinctive tonal color. The EQ section in a mixer allows you to alter a sound by boosting or attenuating specific frequency areas. The MPL 1502 provides independent three-band equalization controls for each of its five mono and five stereo input channels. Each EQ knob is labeled with the maximum amount of cut or boost provided (± 15 dB in the case of the high and low frequencies and ± 12 dB in the case of the middle frequency).

We provided these particular frequency areas because they have maximum impact on musical signals— that’s why they are sometimes known as “sweet spots.” When an EQ knob is in its center detented position (“0”), it is having no effect. When it is moved right of center, the particular frequency area is being boosted; when it is moved left of center, the frequency area is being attenuated. The high EQ control employs what is known as a shelving curve, where only frequencies above the specified area are affected. The low and mid frequency controls employ what is known as a peaking resonant curve (sometimes known as a bell curve), where frequencies both above and below the specified area are affected.

In most instances, the best way to approach equalization is to think in terms of which frequency areas you need to attenuate, as opposed to which ones you need to boost (boosting a frequency area also has the effect of boosting the overall signal; too much EQ boost can actually cause overload— with the accompanying Peak LED warning!). Be aware of the phenomenon of masking, where loud sounds in one frequency range obscure softer sounds in the same range; by cutting EQ “notches” in a loud signal, you can actually make room for a softer one to shine through. And try not to think of EQ as a miracle worker— no amount of equalization can put a singer in tune or remove the distortion from an overloaded input signal! The key is to get the signal right in the first place, by using correct gain structure and mic placement.

Although the specific EQ you will apply to a signal is very much a matter of personal taste, here are a few general suggestions: Boosting the low frequency of instruments such as bass drums or bass guitar will add warmth and make the sound “fatter”; conversely, you may want to attenuate the low frequency compo- nent of instruments such as cymbals, high-hats, and shakers so as to “thin” them out. The mid-range control is particularly effective for vocals— attenuating it can give a vocal performance more of an “FM-radio” feel, while boosting it can help a vocal cut through dense instrumentation. Be careful not to boost high frequen- cies too much or you risk adding hiss to the signal, though just a touch can help add “shimmer” to an acoustic guitar, ride cymbal, or high-hat. Finally, because the MPL 1502 high EQ utilizes a shelving curve, attenuated settings can be used to reduce hiss (which is composed almost exclusively of high frequencies).

0

-15+15

HIGH

0

-15+15

MID

0

-15+15

LOW

19

Image 21
Contents Page Introduction Introduction MPL 1502 System FeaturesIntroduction Samson Guided Tour OverviewGuided Tour Mono and Stereo Channels Guided Tour Mono and Stereo Channels MPL Guided Tour Main SectionGuided Tour Main Section Avis Guided Tour Rear PanelGuided Tour Rear Panel + Signal Ground Connecting The MPL 1502 General SuggestionsStereo channel Sleeve TIP Ring TIP Return Ground Ring Send Setting Up and Using The MPL Setting the Correct Gain Structure PM EST Grounding Techniques Grounding Techniques Using Pan/Balance Using Equalization Using Aux Sends and Returns Using Channel Inserts Applications Application 1 Using The MPL 1502 As a Main Live MixerApplication 2 Using The MPL 1502 As An Onstage Monitor Mixer Application 3 Using The MPL 1502 As a Keyboard Submixer Application 4 Using The MPL 1502 For Recording Equivalent Input Noise Specifications