Theory Of Operation - Source Audio Soundblox Pro User Manual

THEORY OF OPERATION

The Soundblox Pro Multiwave Bass Distortion provides some unique
distortion sounds. In creating this effects pedal, we didn't intend to
duplicate, model, or emulate any existing types of distortion. The types
of algorithms we use to create the distortion are quite different from the
standard set, although with certain settings the result can sound similar.
One of the techniques used is to divide up the input guitar signal into
multiple frequency bands. Each band is separately distorted, and then all
are recombined. Because of this, you can achieve a lot of clarity between
notes on chords with complex harmonies. It's possible to leave several
notes droning, while a melody is played on top. A normal distortion tends
to reduce such playing to mush by compressing and distorting low and
high notes together. Because of the multiple bands, it's also possible to
get several notes feeding back at the same time. The first
(labeled
MULTI BAND ) on the effect knob use band splitting while the last
(labeled ) do not.
8 SINGLE BAND
11
10
09
MULTI BAND
08
07
06
FOLDBACK
05
04
03
NORMAL 02
01
00
CLEAN BOOST / EQ
6 | Theory of Operation
settings
15
OCTAVE
12
13
14
15
NORMAL
16
17
FOLDBACK
18
19 SINGLE BAND
20
21 OCTAVE
22
The shapes of the distortion curves are also different from standard
distortions. Normally, as the input signal voltage rises, the output voltage
also rises, but begins to level off and finally pins (or clips) at a maximum
value. With a foldback curve, for large enough values of the input, the
output will begin to decrease. With more extreme amounts of foldback,
after decreasing for a while, the output can begin to increase again.
Maximum foldback has many regions where the output alternates
between increasing and decreasing. These kinds of curves add a lot of high
frequency content to the output. It also can provide a lot of control over the
sound, based on the level of the input signal. With heavy foldback, chords
containing only octaves and fifths tend to sound best. Other intervals can
cause some strange, although not necessarily undesirable sounds.
Using a special shape of the distortion curve, strong second harmon-
ics can be created, sounding like a note an octave higher. Rolling off the
guitar tone control will help maximize the octave impression. Complex
chords don't typically work well for octave settings. The result is very
sensitive to the input signal level (as long as the
too high) and can give a sort of auto-wah effect. Try dialing down the
guitar volume for some interesting effects.
A conventional distortion effect tends to turn the guitar signal into square
waves. Playing harder only makes the transition from negative clipping to
positive clipping a little bit steeper. With our foldback and octave algo-
rithms, a slightly higher input can have a radical effect on the shape of
the output signal.
The Pro features the same type of algorithms as the Mulitwave
MWB
Bass Distortion but adds user presets and a
other control and parameter options.
control is not set
DRIVE
-band equalizer and many
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Theory of Operation | 7