Samson Acoustic User Manual

Page of 84
13
ENGLISH
About Equalization
The Hartke AC75 or AC150 Acoustic ampli-
fier gives you enormous control over shaping 
the sound of your acoustic rig, using a pro-
cess called equalization.  To understand how 
this works, it’s important to know that 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.  EQ 
controls allow you to alter a sound by boosting 
or attenuating specific frequency areas—they 
operate much like the bass and treble controls 
on your hi-fi amp, but with much greater preci-
sion.  The AC75 or AC150 provides you with one 
most effective tool for shaping the overall tone 
of  your Acoustic sound; a Graphic Equalizer 
providing 12 dB of cut or boost in five narrow 
frequency bands.
The five-band graphic equalizer provides 
seven sliders, each corresponding to a single 
narrow frequency band (100Hz, 315Hz, 1kHz, 
3.5kHz and 10kHz.).  This allows you to “draw” 
the desired tonal response of your system.  
When a slider is in its center position (“0”), it 
has no effect.  When it is moved above center 
(towards “+12”), the particular frequency area is 
being boosted; when it is moved below center 
(towards “-12”), the frequency area is being 
attenuated. We carefully selected these frequen-
cy areas because they have maximum impact 
on acoustic signals.  For example, the lowest 
slider (100 Hz) affects the very lowest audible 
frequencies  (in fact, most humans cannot hear 
below 20 Hz), while the highest four sliders 
affects the mid-range and high frequencies.
To find out how each graphic equalizer slider 
affects the sound of your particular acoustic, 
start with all five bands flat (that is, all five slid-
ers at their “0” center position).