U S E R ’ S G U I D E TM ONBOARD BLENDER WARNING! WE STRONGLY RECOMMEND THAT YOU FAMILIARIZE YOURSELF WITH THE PREAMP CONTROLS BEFORE YOU ATTEMPT TO PERFORM WITH THE ONBOARD BLENDER. FAILURE TO DO SO COULD RESULT IN WAVES OF EAR-SPLITTING FEEDBACK AT HIGH LEVELS. (see Quick Start on page 3.
FISHMAN PREFIX™ ONBOARD BLENDER This fine instrument is equipped with a FISHMAN PREFIX™ ONBOARD BLENDER™. Please read these instructions carefully. If you have any questions or problems, please call our CUSTOMER SERVICE LINE at (978) 988-9665. The ONBOARD BLENDER™ is a guitar mounted preamp that combines the sounds from a supplied FISHMAN ACOUSTIC MATRIX™ under-saddle pickup and a preamp mounted miniature electret condenser microphone.
ACOUSTIC GUITAR SYSTEM QUICK START To successfully combine microphone and pickup signals, it is best to start by presetting the microphone EQ to control feedback, then mixing in the pickup. The PREFIX™ ONBOARD BLENDER™ features three ways to control feedback; a PHASE switch, NOTCH filter and semi-parametric CONTOUR controls. Follow these steps to achieve a strong, feedback-free microphone response. 1.
FISHMAN PREFIX™ ONBOARD BLENDER PREAMP FUNCTIONS BATTERY COMPARTMENT Pull the small tab at the top of the ONBOARD BLENDER™ toward you. The body of the preamp will swing out, revealing the BATTERY COMPARTMENT. Insert a fresh 9V alkaline battery. MICROPHONE TRIM 9V BATTERY PREFIX™ SERIES PREAMP GUITAR BODY MICROPHONE TRIM CONTROL A small circular potentiometer is located on the underside of the preamp just below the battery compartment.
ACOUSTIC GUITAR SYSTEM NOTCH FILTER is effectively off in the full counter-clockwise position. VOLUME CONTROL The VOLUME control affects both microphone and pickup. Goes from very quiet to very LOUD. BASS CONTROL This is a boost/cut shelving tone control. This control affects the pickup signal only. The center detent yields a flat response. CONTOUR This is a wide-range semi-parametric filter. It may be used to shape the instrument's tone or to control feedback (see pages 6 and 7).
FISHMAN PREFIX™ ONBOARD BLENDER SUGGESTED EQ SETTINGS 50 Hz 900 Hz QUIET ANTI-FEEDBACK LOUD 250 Hz - 12 dB 10 kHz + 12 dB - 12 dB - 12 dB + 12 dB + 12 dB Refer to page 3.
ACOUSTIC GUITAR SYSTEM MID CUT 50 Hz 900 Hz QUIET LOUD + 12 dB - 12 dB - 12 dB 250 Hz + 12 dB - 12 dB 10 kHz + 12 dB PHASE BATTERY MIC PICKUP LOW 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. Often the desired mid-cut will fall into the same frequency range as potential microphone feedback.
FISHMAN PREFIX™ ONBOARD BLENDER 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.
ACOUSTIC GUITAR SYSTEM WHY DO I NEED A PHASE SWITCH ? 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. Since an industry standard for polarity has not been established for all sound equipment, the phase switch can compensate for any unintentional differences that might occur between instrument and sound system.
FISHMAN PREFIX™ ONBOARD BLENDER 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 a mic'ed 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.
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 4 mA Power Supply: 9V Alkaline battery (estimated 140 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™ ONBOARD BLENDER ACOUSTIC GUITAR SYSTEM is warranted to function for a period of One (1) Year from the date of purchase.