Gain; Overdrive; Bass - Mesa/Boogie Big Block 750 Owner's Manual

FRONT PANEL CONTROLS:
OVERDRIVE: (Continued)
GAIN control is wired in series with the OVERDRIVE and therefore, it can be used to further fine-tune the amount of overdrive present
in the mix. The effect of the GAIN control is more apparent at the lower region of the OVERDRIVE control, where sweeping the GAIN
is very noticeable. At higher OVERDRIVE settings it has a fairly diminished effect. Generally speaking, the sound will brighter and
more scooped in the mids at lower GAIN settings, while higher settings will produce a fuller, richer sound with less emphasis on upper
harmonics.
We hope you find the OVERDRIVE mode a fun and musically expanding addition to an already amazing sounding preamp. Over time
we believe you wil come to findit an invaluable part of your sound.

GAIN:

This control determines the overall character of the input sensitivity. The lower regions of the control (below 12:00) lend
greater headroom and provide a scooped, brighter personality. The upper harmonics come through more prominently in this area of
the control making the top end sound more transparent and sweet. This region is especially useful for funkier stuff when thumbing is
in order. It keeps the rubber- band feel intact in the lows and mids while voicing the snap just high enough to avoid harshness, or the
TM
S I M U L S T A T E B A S S A M P L I F I E R

OVERDRIVE

INPUT TUNER
MUTE
By experimenting with the amount of gain, you can actually voice the amp to feel as if it bounces just ahead of the groove - or lays back
a little deeper to produce a more Fatback feel. The difference in attack and sustain produces striking results as to how the bassist -
and in fact the whole band - perceives things in the time domain.

BASS:

This control is responsible for the basic mix of low frequencies in the tube pre-amp. The BASS control is an active shelving
type control as opposed to a passive style control. This means that a center Q point has been chosen and this control allows you to
S I M U L S T A T E TM B A S S A M P L I F I E R
OVERDRIVE
INPUT TUNER
MUTE
pletely out of the signal. Conversely, there is a 6db per octave cut beginning at 55Hz going down to 20Hz where the shelving ends with
a cut gain of -20db as the control approaches 7:30 (off).
(Continued)
Note that the GAIN control is still active when the OVERDRIVE is switched into the signal path. The
dreaded "gak" when the G string is plucked.
As the GAIN control is increased past 12:00 a richer, more "well-rounded" voice
becomes dominant and headroom starts to diminish in increments until eventu-
ally, a tube overdrive sound appears as the 12AX7 input tube is driven into satura-
tion.
GAIN
The region between 12:00 and 2:30 is where the classic, warm tube sound re-
sides and within this narrow band you will discover a world of tone. Tiny incre-
ments here produce subtle, but important differences in the attack characteristic
which in turn, feel like changes in the time domain.
either boost or cut that frequency. This control differs from the low bands of
the Parametric in that it has a broader Q point with a more gentle ramp as
opposed to the Parametrics' narrow Q that is used with a separate GAIN
control.
The BASS control is actually a gain and frequency control all rolled into
one with the Q center at 55Hz and harmonics in both low and high direc-
GAIN BASS
tions are affected because of its broader band nature. As the control is
increased past 12:00 there is a 6db per octave rise in gain with the fre-
quency topping out at 321Hz. With 12:00 straight-up representing "flat" (a
no boost/no cut setting). As the BASS control is dialed below 12:00, 55Hz
and all associated harmonics are reduced and eventually notched com-
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