Hartke B Series B600 User Manual

Contents

Hartke B Series B600 User Manual Manual pdf 13 page image

99Using Equalization and ShapeThe Hartke Systems B Series Bass Amplifier gives you enormous control over shaping the soundof your bass, using a process called equalization. To understand how this works, it’s important toknow 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 tonalcolor. The B Series EQ controls allow you to alter a sound by boosting or attenuating specific fre-quency areas—they operate much like the bass and treble controls on your hi-fi amp, but withmuch greater precision.The B Series offers three bands of equalization. Each EQ knob (labeled Bass, Mid, and High,respectively) affects a different frequency area (100 Hz, 830 Hz, and 5 kHz, respectively) andprovides approximately 15 dB of boost and attenuation. We carefully selected these frequencyareas because they have maximum impact on bass signals. For example, the Low (100 Hz) con-trol affects the very lowest audible frequencies (in fact, most humans cannot hear below 20 Hz),while the High (5 kHz) control affects the “twang” of a bass string.When an EQ knob is in its center detented position (“0”), it is having no effect. When it is movedright of center, the particular frequency area is being boosted; when it is moved left of center, thefrequency area is being attenuated. Turning all EQ controls up the same amount will have virtu-ally the same effect as simply turning up the Volume; conversely, turning them all down the sameamount will have virtually the same effect as turning down the Volume. Both approaches arepointless (after all, that’s why we gave you a Volume control!)In many instances, the best way to deal with equalization is to think in terms of which fre-quency areas you need to attenuate, as opposed to which ones you need to boost. Be awarethat boosting a frequency area also has the effect of boosting the overall signal; specifically, toomuch Low EQ boost can actually cause overload distortion or even harm the connected speaker.In addition, the B600 and B900 models provide a unique Shape control which employs a notchfilter to remove specific frequency areas. At the same time, it overlays a special equalization curvethat is designed to improve the sound of electric bass instruments. This curve provides boostat certain frequency areas and attenuation at other frequency areas. As the Shape knob is turnedclockwise, the notch filter is imposed on higher frequency areas; as it is turned counterclock-wise, the filter is imposed on lower frequency areas. At the fully clockwise position, the filter isapplied to the 1 kHz frequency area, making for a deep, rich tone; at the fully counterclockwiseposition, the filter is applied to the 90 Hz frequency area, making for a bright, twangy tone.The specific EQ (and/or Shape) you will apply to your bass signal is very much dependent uponyour particular instrument and personal taste and playing style. However, here are a few generalsuggestions:B00_OM_5L_v5.indd 9 3/30/06 11:37:52 AM