U S E R ’ S G U I D E
FISHMAN PREFIX™ PLUS This fine instrument is equipped with a FISHMAN PREFIX PLUS™ ACOUSTIC GUITAR SYSTEM. Please read these instructions carefully. If you have any questions or problems, please call our CUSTOMER SERVICE LINE at (978) 988-9665. The PREFIX PLUS™ is an instrument-mounted pickup / preamp system that offers total control of your amplified guitar sound.
ONBOARD ACOUSTIC GUITAR SYSTEM PREAMP FUNCTIONS BATTERY COMPARTMENT Pull the small tab at the top of the PREFIX PLUS™ toward you. The body of the preamp will swing out, revealing the BATTERY COMPARTMENT. Insert a fresh 9V alkaline battery. ENDPIN JACK The PREFIX PLUS™ has no ON/OFF switch. It is turned on only when an instrument cable is plugged into the endpin jack. To conserve the battery, remove the instrument cable from the endpin jack when the unit is not being used.
FISHMAN PREFIX™ PLUS VOLUME CONTROL Controls the overall gain of the PREFIX PLUS™. Goes from very quiet to very loud. BASS CONTROL This is a boost/cut shelving tone control. The center detent yields a flat response. 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 center detent yields a flat response.
ONBOARD ACOUSTIC GUITAR SYSTEM SUGGESTED EQ SETTINGS MID CUT 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" midcut at 800 Hz.
FISHMAN PREFIX™ PLUS FINGERSTYLE This setting will add fullness to the bass and definition to the treble.
ONBOARD ACOUSTIC GUITAR SYSTEM CUT THROUGH For cutting through a live band mix at high volumes.
FISHMAN PREFIX™ PLUS WHAT IS PHASE? Phase is the relationship between two signals or soundwaves originating from the same instrument. For our purposes, phase relationships are expressed as being either "in phase" or "out of phase". In phase tends to enhance, while out of phase tends to suppress the natural characteristics and acoustic tendencies of an instrument. A simple way to determine the quality of phase (in or out) of two sounds is to compare phase switch settings at low volumes.
ONBOARD ACOUSTIC GUITAR SYSTEM PHASE, Continued from Page 8 WHAT IS THE PHASE SWITCH FOR? The phase switch is useful for two reasons: 1. Due to the interactive and changing nature of phase, acoustic amplification depends on maintaining optimum phase relationships between amplified instruments, sound systems and venues. 2.
FISHMAN PREFIX™ PLUS PHASE, Continued from Page 9 Here's why: A typical guitar has a cavity resonance of about 100 Hz. This is the frequency that generally feeds back when the guitar and speaker are in phase. 100 Hz has a wavelength of about 11 feet. Phase inverts 180° for every 1/2 a frequency's wavelength. In this case, 1/2 the wavelength is about 5 1/2 feet.
ONBOARD ACOUSTIC GUITAR SYSTEM SPECIFICATIONS Nominal Input Level: -20 dBV Input Overload: (20 Hz - 20 kHz)-2 dBV Input Impedance: 20 M Ohms Output Impedance: Less than 3.5 k Ohms Nominal Output Level: -12 dBV THD: Less than .04 %, -20 dBV input Signal to Noise Ratio: 77 dB (A weighted referred to nominal -20 dBV input) Current Drain: Less than 3.5 mA Power Supply: 9V Alkaline battery (estimated 160 hours continuous use with low battery indicator at 6.
LIMITED WARRANTY INSTALLATION BY A QUALIFIED PROFESSIONAL REPAIRMAN IS STRONGLY RECOMMENDED. FISHMAN TRANSDUCERS WILL NOT BE RESPONSIBLE FOR ANY DAMAGES THAT MAY RESULT FROM IMPROPER INSTALLATION. The FISHMAN PREFIX™ PLUS ACOUSTIC GUITAR SYSTEM is warranted to function for a period of One (1) Year from the date of purchase.
