ment of your guitar. The battery will fit only one way to assure
correct polarity. Plugging a
1
/
4
” shielded guitar cable into the jack
on the guitar activates the electronics in your guitar. Please note
that the tuner will operate without "plugging in." After connecting
the guitar, plug into a PA or acoustic guitar amp for best results.
Controls
Please refer again to figures 1+2 to help yourself associate control
names with their functions.
Volume
This slide control allows you to set the output level of the preamp.
Moving the slider toward the top increases the output level. The
OP-24Plus/OP-24Plus C can output a very potent signal, so be
careful not to "overdrive" your amp or mixer. If you notice any
unwanted signal coloration, just reduce the output level of the
guitar with this control.
Battery Low
This indicator performs two functions. First, when you plug in a
cable to the output jack, it will flash briefly to indicate that a
battery is present. If no flash is evident, your battery is either dead
or not installed. Secondly, this indicator will illuminate (and stay
on) if the voltage of the battery installed in the guitar dips below
about 7 volts. Replace the battery as soon as possible. With aver-
age use, expect 100 hours of operation per battery.
EQ Controls
The EQ section allows you to accent or attenuate certain frequency
bands within the guitar’s audio spectrum. When all of the controls
are in the center (detent) position, signals pass through the circuit
unaltered. Raising an EQ knob above the center position increases
the energy contained within that spectrum. Likewise, moving the
control below the center position decreases the signals within that
band.
The OP-24Plus and OP-24Plus C preamp offers
±
12dB control
simultaneously over three discrete ranges of the guitar’s sonic spec-
trum. In addition, with the Mid-Shift switch, you can change the
center frequency of the Mid EQ control by roughly one octave.
The Low EQ control allows you to increase or reduce the sound in
the bass region. Raise this control above the center position to
add fullness or bottom to your sound. De-emphasizing this band
results in a lighter, less ponderous sound quality.
The High EQ control performs similarly to the “Low” control ex-
cept that its effect shapes the high frequency, or treble band. In-
crease this control for bright or airy sounds, or decrease for darker
or round tonalities.
Much like the High and Low controls, the Mid-band control adds
coloration to one of two user-selectable midrange frequencies.
With the Mid-Shift switch in the 400Hz position (down), the mid
EQ is effective controlling “nasal” tone qualities while in the 1KHz
position, the mid control can add punch in upper mids or help
"round off" the attack present in this frequency spectrum.
Introduction
Congratulations and thank you for selecting an Ovation Acoustic/
Electric guitar equipped with the OP-24Plus or OP-24Plus C
preamp. Please read this brief manual thoroughly to insure you
get the best performance from your new Ovation.
The Ovation OP-24Plus/OP-24Plus C preamps access a wide range
of "studio-quality" contemporary acoustic/electric guitar sounds
offering a player tremendous control and sonic flexibility. The cir-
cuitry is exceptionally quiet and adds no unwanted coloration. In
addition, the OP-24E features a built-in chromatic tuner.
Referring to fig. 1 or fig. 2, you’ll see the layout and nomenclature
associated with the control features of these units.
Preamp Features & Functions
The preamp's audio circuitry is whisper quiet with very low distor-
tion (see specifications table). Tone control is greatly enhanced
with a "three-and-a-half" (we'll talk about that later) band graphic
equalizer. Moreover, you can connect your guitar to a wide range
of audio amplification and recording equipment with the preamp's
standard
1
/
4
” Hi-Z, unbalanced phone jack output.
Connections
Near the endpin of a guitar featuring these preamps, you’ll notice
a
1
/
4
” phone jack. This jack provides the signal from the preamp
to any of a number of audio devices... mixers, effects, amps.
The Hi-Z Connection
To connect your guitar to any high impedance (Hi-Z) acoustic gui-
tar amp or mixer, use a standard, shielded,
1
/
4
” guitar cable in-
serted into the
1
/
4
” jack on the guitar. The preamp will drive most
audio equipment with rated inputs down to about 1000 Ohms
(this mean you can connect to almost anything). If you have a
battery installed in the guitar, you’re ready to play.
Operation
Make sure a fresh 9V battery is installed into the battery compart-
Figure 2
Figure 1
