9
6) Electronics for all models
Alien Acoustic Bass
Pickups – Piezo variant
4-string = Fishman Acoustic Matrix
Electronics - Fishman Prefix Plus
TIP:
To increase the life of your battery unplug
the cable from the guitar between playing sessi-
ons.
If you need more information about the electro-
nics, please download the wiring diagrams online
at www.warwick.de.
1) Notch Filter: This is a fixed-level, variable-frequency filter for eliminating feedback or
unwanted resonance. The affected frequency is variable from 40 to 500 Hz. The Notch
Filter is effectively turned off in the full counterclockwise position.
2) Volume Control: Controls the overall gain of the Prefix Plus™.
3) Bass Control: This is a boost / cut shelving tone control for low frequencies.
4) Contour: This is a wide-range semi-parametric filter. It is used to selectively shape the
instrument’s tone. The Contour Level slider controls the amount of boost or cut applied to
the selected contour frequency. The Contour Frequency slider determines the frequency
band that is boosted or cut by the Contour Level control. The frequency is variable from
250 to 10 kHz.
5) Treble Control: This is a boost / cut shelving tone control for high frequencies.
6) Brilliance Control: This is a resonant-style boost / cut filter that adds presence to the
sound.
7) Phase Switch: The Phase Switch compensates for acoustic phase differences that often
occur between instrument and speaker. It can be used as a tone filter at low volume levels
or as a feedback filter at high levels. The Phase Switch can correct any electrical phase
difference between the Prefix™ system and an outboard instrument microphone. Flip the
Phase Switch several times and use your ear to find the optimum setting. The best position
for the Phase Switch may change depending on the sound system and/or venue acoustics.
8) Frequency: You can scoop out harsh midrange by setting the Frequency slider slightly
above center with the Contour level cut to taste below the center detent. You can also cut
midrange by boosting the Bass and Treble sliders to realize an “implied” mid cut at 800 Hz
