Fishman_Prefix_On-Board_Blender_Manual 电路图.pdf

TM ONBOARD BLENDER USERS GUIDE 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.) RadioFans.CN 收音机爱 好者资料库 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. The microphone, shock-mounted on the underside of the preamp chassis, captures the elusive natural ambience and resonance of the guitars sound chamber. The ACOUSTIC MATRIX pickup delivers a clear, articulate sound with emphasis on string definition and attack. When combined, the two signals produce a powerful and cohe- sive acoustic guitar tone that is much greater than the sound of either microphone or pickup alone. The ONBOARD BLENDERs preamp module incorporates a unique flip-top battery compartment for easy access. Levels are set by the master VOLUME and BLEND con- trols. A variable NOTCH filter, shelving BASS a PHASE switch, NOTCH filter and semi-parametric CONTOUR controls. Follow these steps to achieve a strong, feedback-free microphone response. 1. Before plugging in, set all controls as follows: NOTCH and VOLUME fully counter-clockwise All EQ sliders at center position BLEND slider at MIC position 2. Plug in the instrument (see THE PREAMP section) with your amplifier set as desired. 3. Slowly increase the VOLUME until the guitar and speaker are approximately the same level. Play the lower strings and flip the PHASE switch. Leave the switch in the position that sounds the deepest and clearest. (See page 8) 4. Slowly increase the volume until the instrument starts to rumble or howl with low to mid level feedback (100-200 Hz). 5. Adjust the NOTCH filter until the feedback is eliminated. 6. Slowly increase the VOLUME again, until you hear a squeal (high frequency feedback). 7. Lower the CONTOUR Level all the way down. Slowly adjust the Contour FREQUENCY slider until the feedback is eliminated. Raise the CONTOUR Level slider (if possible) to just below the threshold of feedback. 8. Gradually mix in the pickup signal by adjusting the BLEND slider. The pickup signal will add significant attack and definition to your sound. 9. Adjust the BASS and TREBLE controls as desired. Please note that these controls will affect pickup signal only. 10.Double check the PHASE switch position until you find the clearest response. 11.Play your guitar as loud as you want. See diagram on page 6 RadioFans.CN 收音机爱 好者资料库 FISHMAN PREFIX ONBOARD BLENDER 4 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 BAT- TERY COMPARTMENT. Insert a fresh 9V alkaline battery. MICROPHONE TRIM CONTROL A small circular potentiometer is located on the underside of the preamp just below the battery compartment. This control is used to calibrate the microphone gain in relation to the pickup. To use this control, set the BLEND slider to the center position and, with a small screwdriver, adjust the potentiometer until both the microphone and pickup levels are balanced. ENDPIN JACK The ONBOARD BLENDER 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. NOTE: Plug an instrument cable into the endpin jack before you plug into the sound equipment. Doing so will prevent loudspeaker damage. BATTERY LOW LED When plugging into the endpin jack, the LOW BATTERY light will flash momen- tarily, indicating that the power is on. When the LOW BATTERY light stays on, it is time to change the battery. CONTROLS NOTCH FILTER This is a fixed level, variable-frequency filter for eliminating feedback or unwanted resonance. The affected frequency is variable from 50 to 900 Hz. The GUITAR BODY PREFIX SERIES PREAMP MICROPHONE TRIM 9V BATTERY 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 instruments tone or to control feedback (see pages 6 and 7). The CONTOUR control affects both the pickup and microphone. The CONTOUR Level slider controls the amount of boost or cut applied to the selected Contour FREQUENCY. The center detent yields a flat response. The Contour FREQUENCY slider determines the frequency band that is boosted or cut by the CONTOUR Level control. The frequency is variable between 250 Hz and 10 kHz. TREBLE CONTROL This is a boost/cut shelving tone control. This control affects the pickup signal only. The center detent yields a flat response. 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 a feedback filter at high levels. Whenever you play through a different sound system or at a different venue, flip the PHASE switch several times and use your ear to find the optimum setting. BLEND CONTROL This control determines the balance between microphone and pickup signals. This control can be used as a feedback escape hatch if you ever need to instantly shut off the microphone during a performance. 5 FISHMAN PREFIX ONBOARD BLENDER 6 SUGGESTED EQ SETTINGS ANTI-FEEDBACK Refer to page 3. BRILLIANCE If you are playing through an electric guitar amplifier or have dead strings on the instrument, you can brighten up your sound by setting the Contour FRE- QUENCY slider to 10 kHz and raising the CONTOUR Level to taste. If you plan to play at high stage volume levels, dial in more pickup than microphone to avoid feedback. PHASE LOW BATTERY 10 kHz250 Hz -12 dB+12 dB +12 dB-12 dB +12 dB-12 dB 50 Hz900 HzQUIETLOUD PICKUPMIC PHASE LOW BATTERY 10 kHz250 Hz -12 dB+12 dB +12 dB-12 dB +12 dB-12 dB 50 Hz900 HzQUIETLOUD PICKUPMIC ACOUSTIC GUITAR SYSTEM 7 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. Often the desired mid-cut will fall into the same frequency range as potential microphone feedback. This is your lucky day! You can also cut midrange (pickup only) by boosting the BASS and TREBLE sliders to realize an implied mid-cut at 800 Hz. FINGERSTYLE This setting will add fullness to the bass and definition to the treble. PHASE LOW BATTERY 10 kHz250 Hz -12 dB+12 dB +12 dB-12 dB +12 dB-12 dB 50 Hz900 HzQUIETLOUD PICKUPMIC PHASE LOW BATTERY 10 kHz250 Hz -12 dB+12 dB +12 dB-12 dB +12 dB-12 dB 50 Hz900 HzQUIETLOUD PICKUPMIC FISHMAN PREFIX ONBOARD BLENDER 8 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 sup- press 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 com- pare phase switch settings at low volumes. IN PHASE In phase is when the wave- forms of two sounds originat- ing from the same instrument are similarly aligned in time. Similar phase is like looking at yourself in a mirror: your reflection directly follows your movement. OUT OF PHASE Out of phase is when the waveforms of two sounds orig- inating from the same instru- ment are aligned such that the upper peak of one wave occurs at the same moment in time as the lower peak of the other.Out of phase is like looking at yourself in a live video monitor; the image you see is similar, but the per- spective is shifted. When you move to the right, the image appears to move to your left. UPPER PEAK LOWER PEAK ACOUSTIC GUITAR SYSTEM 9 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. APPLICATIONS In any situation where the miced instrument faces a loudspeaker, there will be an interactive phase relationship between the two. This usually occurs with stage amps, side fill and floor monitors at close distances. LOW VOLUME AMPLIFICATION At low volumes, when a miced instrument and speaker are at similar levels and are in phase, the sound is full and solid, with the lower frequencies emphasized. When a miced instrument and speaker are out of phase at low levels, the bass frequencies cancel out to some extent. The resulting sound is somewhat unnat- ural and unbalanced compared to in phase. HIGH VOLUME LEVELS At high volume levels, when a miced instrument and speaker are in phase, the sound pressure from the speaker will excite the instruments sound chamber, creating a feedback loop at the instruments lowest octave. This cavity reso- nance feedback can be dealt with by putting the miced instrument and speaker out of phase or by adding equalization. A. USING THE PHASE SWITCH TO REDUCE FEEDBACK. Inverting the PHASE switch will put the miced instrument and speaker out of phase with each other, cancelling the low frequency feedback. If you move from your position on stage more than a few feet, you may have to invert the PHASE switch again to maintain an out of phase relationship between the miced instrument and speaker. Continued . FISHMAN PREFIX ONBOARD BLENDER 10 Continued from Page 9 Heres why: A typical guitar has a cavity resonance of about 100 Hz. This is the frequency that generally feeds back when a miced guitar and speaker are in phase. 100 Hz has a wavelength of about 11 feet. Phase inverts 180 for every 1/2 a frequencys wavelength. In this case, 1/2 the wavelength is about 5 1/2 feet. If you set your PHASE switch to eliminate cavity resonance (out of phase) and then move 5 1/2 feet towards or away from the speaker, you will effectively put the miced guitar/speaker relationship at 100 Hz back in phase;in the line of fire for low frequency feedback. B. USING THE NOTCH FILTER TO REDUCE FEEDBACK Notching out instrument cavity resonance will eliminate the low frequency feed- back problem completely. The advantages to using notching equalization are: The physical distance from the speaker will no longer be a factor for potential low frequency feedback. The miced instrument/speaker can remain in phase, maintaining a more nat- ural and balanced response. DISTANCE:5 7 PHASE INVERTED 180PHASE INVERTED 180 11 417 22 7 The PHASE switch on the ONBOARD BLENDER in effect electronically moves your instruments position relative to the speaker by inverting the phase 180 every time you flip it. ACOUSTIC GUITAR SYSTEM 11 TM ONBOARD BLENDER PICKUP ONLY 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 6.5V) Notch Filter Range:50Hz - 900 Hz (-15 dB) Bass Control Range: 12 dB at 60 Hz 3 dB at 350 Hz Treble Control Range: 12 dB at 10 kHz 3 dB at 2.4 kHz Contour Control Range: 12dB (adjustable from 250 Hz to 10 kHz) Q = 0.5 All specifications subject to change without notice. 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. If the unit fails to function properly within the warranty period, free repair and the option of replacement or refund in the event that FISHMAN is unable to make repair are FISHMANs only obligations. This warranty does not cover any consequential damages or damage to the unit due to misuse, accident, or neglect. FISHMAN retains the right to make such determination on the basis of factory inspection. Products returned to FISHMAN for repair or replacement must be shipped in accordance with the Return Policy, as follows. This warranty remains valid only if repairs are performed by FISHMAN. This warranty gives you specific legal rights and you may also have other rights which may vary from state to state. RETURN POLICY To return products to FISHMAN TRANSDUCERS, you must follow these steps. 1. Call FISHMAN TRANSDUCERS at 978-988-9199 for a Return Authorization Number (“RAN”). 2. Enclose a copy of the original Bill of Sale as evidence of the date of purchase, with the product in its original packaging and a protective carton or mailer. 3. FISHMAN TRANSDUCERS technicians will determine whether the item is covered by warranty or if it instead has been damaged by improper customer installation or other causes not related to defects in material or workmanship. 4. Warranty repairs or replacements will be sent automatically free of charge. 5. If FISHMAN TRANSDUCERS determines the item is not covered by warranty, we will notify you of the repair or replacement cost and wait for your authorization to proceed. FISHMAN TRANSDUCERS 340-D Fordham Road Wilmington MA 01887 USA Phone 978-988-9199 Fax 978-988-0770 009-087-004 3-98 LIMITED WARRANTY