F
R O N T
P
A N E L
High Gain input
This is a high-sensitivity input. If your guitar has hot pickups,
then plugging into it makes it easy to overdrive the preamp section, creating harmonic dis-
tortion. Guitars equipped with low-output pickups seem hotter than usual when plugged
into this input.
Low Gain input
This is a low-sensitivity input. Guitars plugged into it have more headroom before dis-
tortion sets in (meaning that you can crank up a channel’s volume a little louder before you experience pre-
amp distortion). This is a good choice for a clean overall sound, and is especially well-suited to active pickups
or guitars equipped with preamps.
Channel 1
Both channels are voiced differently, and
Channel 1 is definitely geared toward creating impres-
sive overdrive (think of a “British” tone). Grit, grunge,
dirt—whatever you’re looking for in the distortion
department is here, from sweet and singing to hard-dri-
ving to maximum sustain. Note: Like the controls on
all classic amps, the Treble, Middle, and Bass interact,
creating smooth, musical tone changes. All three controls operate with even response throughout their ranges.
Volume (with channel-select switch)
Although it’s labeled “Volume,” this control does a lot more
than determine how loud Channel 1 is. It regulates the preamp’s volume and works with the Master to set the
level and distortion amount. A simple rule of thumb is, the higher the Volume is set, the more distortion you
get. The pull switch selects which channel is active. Its circuitry is designed so that you don’t hear a pop or click
when the channel is changed. (The FS-7 footswitch also selects channels; the Volume’s pull switch must be
pushed in for the FS-7 to choose channels. See page 9 for more on the FS-7 and its functions.)
Bass
The “chunk” and support that form the backbone of your tone come from this control. Its effect on
your overall sound will be different at high and low volumes due to the speaker’s characteristics and how
much distortion you use.
Middle
The midrange circuit provides the “meat” that fills out your sound. It has a slight notch in the fre-
quency spectrum at about 550 Hz, and turning the knob alters the depth of that notch, letting you change
the overall voicing of your tone.
Treble
Whether you’re looking for edge, slash, or just a little shimmer, this knob’s for you. Like the Bass
control, the apparent effect of the Treble changes with the loudness and distortion you dial in.
Master (with Pull Boost switch)
Think of the Master as a sort of governor that sets the maximum
loudness for the channel. Also, think of it as the second half of what the Volume knob does. With the Volume
turned down and the Master up, there’s less distortion than if you crank up the Volume and set the Master lower.
The Master control comes after all distortion and tone-shaping on Channel 1, so its level doesn’t have a bearing
on your basic tone. When you pull out the Boost switch on Channel 1, it adds a whole range of harmonics, and
not just gain. This is easy to hear by playing a power chord and comparing its sound with the switch pushed in
and pulled out. With the switch activated, the tone blooms, going from fat to ferocious.
8
7
6
5
4
Channel 2
Channel 1
Hundred
Duo Twelve
PULL
SELECT
PULL
BOOST
STANDBY
POWER
LOW
GAIN
HIGH
GAIN
VOLUME
BASS
MIDDLE
TREBLE
MASTER
VOLUME
TREBLE
MIDDLE
BASS
MASTER
REVERB
PRESENCE
HANDCRAFTED BY RIVERA RESEARCH & DEVELOPMENT
SUN VALLEY, CA USA
INPUTS
PULL
BRIGHT
PULL
NOTCH
PULL
NINJA
10
9
8
76
5
4
3
2 1
10
9
8
76
5
4
3
2 1
10
9
8
76
5
4
3
2 1
10
9
8
76
5
4
3
2 1
10
9
8
76
5
4
3
2 1
10
9
8
76
5
4
3
2 1
10
9
8
76
5
4
3
2 1
10
9
8
76
5
4
3
2 1
10
9
8
76
5
4
3
2 1
10
9
8
76
5
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2 1
10
9
8
76
5
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3
2 1
10
9
8
76
5
4
3
2 1
LOW
GAIN
HIGH
GAIN
INPUTS
Channel 1
PULL
SELECT
PULL
BOOST
VOLUME
BASS
MIDDLE
TREBLE
MASTER
10
9
8
76
5
4
3
2 1
10
9
8
76
5
4
3
2 1
10
9
8
76
5
4
3
2 1
10
9
8
76
5
4
3
2 1
10
9
8
76
5
4
3
2 1
