Bass Eq Control; Bass Equalization Curves - zapco Reference Series 2 User Manual

In vehicle sound systems they have a tendency to peak at about
100Hz to 120Hz and to roll off after that. This leaves a hole in the bass
response in the 40Hz to 50Hz range.
To compensate for this effect, ZAPCO has provided all Reference
Series amplifiers with a variable Bass equalization circuit. Each amplifier
has a "Bass Boost" control, which allows adjustment of the bass from 0dB to
as much as 18dB. This adjustment is made at a frequency of 44Hz.
Use the Bass EQ with caution. Too much equalization can easily
cause amplifier clipping and may even damage your speakers.

Bass EQ Control

Bass Equalization Curves

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