POWER AMPLIFIERS From Fender Pro Audio Owner's Manual for SPL-M500 P/N 050253 REV B Fender Musical Instruments 7975 North Hayden Road, Scottsdale, Arizona 85258 U.S.A. Fender knows the importance of sound reinforcement. From the simple box-top mixer to today's professional touring concert systems, the need to communicate, to make the connection between the performer and the audience is foremost in Fender's mind. Perhaps no other single piece of gear can make or break your band's sound. You see, your sound system is more than just a combination of dials, wires and speakers. It is an integral part of the audio chain and should be treated with special care and attention to detail. At Fender, we know what building quality musical instruments and sound reinforcement equipment is all about. In fact, many of the world's best sounding electric musical instruments and sound reinforcement equipment proudly wear the Fender name. Whether you need a simple box top powered mixer for your Saturday afternoon jam, or a professional full-size concert system, Fender has the sound reinforcement equipment to meet your needs. Likewise, your decision to purchase Fender pro audio gear is one you will appreciate with each performance for years to come. Wishing you years of enjoyment and a heartfelt thank you, Bill Schultz Bill Schultz Chairman Fender Musical Instruments Corporation SPL-M500 TM STAGE MONITOR POWER AMPLIFIER INTRODUCTION 500 Watts into 2 Variable high pass filter (12 dB per octave, sweeping from 12 Hz to 150 Hz) Variable low pass filter (12 dB per octave, sweeping from 2.5 kHz to 30 kHz) Three independent variable notch filters for feedback control Built in switchable DELTACOMPTM Compressor Forced air cooling with automatic 2-speed fan Bi-amp patch point connect for versatility in larger monitor systems Balanced TRS phone jack and female 3-pin XLR input connectors Rugged "road proof" 14 gauge steel chassis Two rack space (3.5 in, 8.8cm) chassis Optional rear rack supports (P/N 040661) WARNING: -To reduce the risk of fire or shock hazard, do not expose this amplifier to rain or moisture. -No user serviceable parts inside, refer servicing to qualified personnel only. -This amplifier must be earth grounded. Thank you for your purchase of a Fender SPL-M500 Stage Monitor Power Amplifier. We are sure you will find it to be a useful and unique product, providing years of trouble free service in both permanent and portable applications. Although intended primarily for portable stage monitor use, the SPL-M500 is also effective in sound reinforcement applications where fixed microphones are used and feedback is a problem. Employing a unique design, the SPL-M500 provides a powerful tonal control system which fights feedback while optimizing sound. This design is comprised of a sweepable high pass filter, a sweepable low pass filter and three advanced narrow band notch filters. This manual is arranged into four sections: A description of the SPL-M500 panel features. A section on basic connections and wiring. A guide on operating the SPL-M500. Product specification sheet. 3 DESCRIPTION OF FEATURES E F INPUT LEVEL +6dB LOW NOTCH DEPTH 0dB MID NOTCH DEPTH 0dB 2k -3 4k -6 HIGH NOTCH DEPTH 0dB 4k -3 9k -6 16 60 POWER 120 ON 225 0dB 70 430 -3 700 -6 1k FLAT 150 LOW FREQ. ROLLOFF 12k DELTACOMPTM 4k 35k 50 -0 0 500 -12 MAX. 400 5k -12 MAX. 800 10k -12 MAX. FREQUENCY FREQUENCY FREQUENCY 2k FLAT HIGH FREQ. ROLLOFF POWER F E E D B A C K C O N T R O L F I LT E R ABC BC BC D G H FRONT PANEL A. INPUT LEVEL CONTROL - Variable attenuator controls the amplifier's input sensitivity. Control settings can vary between +8dB (fully up) and infinite attenuation (fully down). At the full up position, a 360mV input signal is required for rated output. At 0, a 360mV input signal will yield an output power of 1/8th rated power. B. NOTCH FREQUENCY CONTROL - Higher notch frequencies are selected as the knobs are rotated in the clockwise direction. Each knob covers a specified frequency range, but two adjacent knobs do have overlapped frequencies. This feature is intentional. Refer to the "Hints and Precautions" found on page 7 for details concerning this feature. C. NOTCH DEPTH CONTROL - These sliders provide attenuation control for each notch filter frequency band. At the highest position, 0dB of attenuation is obtained. At the lowest position, they can provide more than 25 dB of attenuation at the selected frequency. Refer to the "Hints and Precautions" found on page 7 for details concerning this feature. D. HIGH FREQUENCY ROLL OFF CONTROL (LOW PASS FILTER) - Useful for smoothing out "edgy" sounding speakers. When this knob is fully in its clockwise position, all signals below 30 kHz are allowed to enter the power amplifier. If set fully counter clockwise, only signals below 2.5 kHz will be 4 I permitted to pass through. Start with this control set at 30 kHz. If the performers complain of "edgy" sounding monitors and want smoother sounding ones, rotate this control counter clockwise until they are pleased with the sound. E. LOW FREQUENCY ROLL OFF CONTROL (HIGH PASS FILTER) - Useful for removing rumble (mechanical noise) or resonance and L.F. leakage. When this knob is fully in its counter clockwise position, all input signals above 12Hz are allowed to pass. When it is positioned fully clockwise, only frequencies above 150 Hz are permitted to enter the power amplifier. Start with this control set at 12 Hz. If the performers want crisper sounding sounding monitors slowly rotate this control clockwise until they are pleased with the sound. F. POWER LED INDICATOR - LED is illuminated when the monitor amplifier is turned on, and the AC mains voltage is present. If the indicator does not light when the power switch is turned on (and does not trip the circuit breaker), check the AC power supply and fuse. G. DELTACOMPTM SWITCH - This switch activates the internal compressor circuit. Peak clipping is minimized when the compressor circuit is active. This will also "clamp" feedback, helping protect your monitor speakers. During normal operation, keep this switch engaged. DO NOT BLOCK FAN OPENING TYPE: PR 308 OUTPUTS SERIAL NUMBER PATCH POINT RETURN SEND BALANCED INPUTS PARALLEL SPKR. JACKS 500W 900W FUSE F10A 250V CAUTION: CHASSIS SURFACE HOT WARNING: TO REDUCE THE RISK OF FIRE OR ELECTRIC SHOCK , DO NOT EXPOSE THIS EQUIPMENT TO RAIN OR MOISTURE 2 MIN TOTAL CLASS 2 WIRING UTILISER UN FUSIBLE DE RECHANGE DE MEME TYPE ET CALIBRE ATTENTION: TO REDUCE THE RISK OF FIRE, REPLACE FUSE WITH SAME TYPE AND RATING CAUTION: AVIS: RISQUE DE CHOC ELECTRIQUE NE PAS OUVRIR ATTENTION: SUPERFICIE DE CHASSIS CHAUDE J K L L MN O O H. PEAK LED INDICATOR - The red Peak LED Indicator illuminates when the output voltage of the amplifier reaches clipping (maximum output voltage). The threshold for the peak indicator automatically adjusts for load impedance and supply voltage variations. I. POWER SWITCH - The power switch turns the unit on and off. The LED (item F) is illuminated when the amplifier is turned on and main voltage is present. M. PATCH POINT RETURN CONNECTOR Provides the possibility of using the power amplifier by bypassing the preamp section of the unit. When this connector is used, the preamp is totally disconnected from the power amplifier section. If nothing is plugged into this jack, it normally takes its signal from the preamp output, via the PATCH POINT SEND jack. (See section N). N. PATCH POINT SEND CONNECTOR - This connection can be used with the patch point return connector, if further signal processing by an external unit is desired. Processing could include the insertion of a 1/3 octave graphic equalizer for tonal shaping, an external compressor/limiter and/or the insertion of an active electronic crossover network for bi-amped monitor systems. The output of this jack is normally tied to the patch point return connector. Using this connector will not disconnect the preamp section from the power amplifier section. O. BALANCED INPUT CONNECTORS - This unit provides two types of input connectors: a 1/4 inch TRS and an XLR female connector. The 1/4 inch TRS connector polarities are: tip (+), ring (-), and sleeve (ground). The XLR female connector polarities are: pin 2 (+), pin 3 (-), and pin 1 (ground). REAR PANEL J. POWER CORD - The SPL-M500 is equipped with a grounding type supply cord to reduce the possibility of shock hazard. Be sure to connect it to a grounded AC receptacle. DO NOT ALTER THE AC PLUG. K. EXTERNAL FUSE - When necessary, replace the external fuse ONLY with one of the same type and rating as shown on the label next to the external fuse holder. L. OUTPUT SPEAKER JACKS - Two parallel-wired, 1/4"output connectors are provided capable of providing 500 Watts of power into a 2 minimum load total. (One 2 speaker or two speakers at 4 each). 5 BASIC CONNECTIONS and WIRING Power and audio signal cables are the most common sources of sound system failure. Well made and carefully maintained cables are essential to the reliability of the entire system. If long speaker cables are required, make sure the wire is of sufficient size to transfer all of the available amplifier power to the speakers rather than absorbing power itself. As a rule of thumb, the larger the wire the better (larger wire has smaller "gauge numbers"). Below are two charts listing speaker wire gauges and recommendations for best results. Larger diameter (small gauge number) wire is expensive and long cables made from it are heavy. Rather than running long speaker cables, it is better to locate power amplifiers near speakers and run a line-level signal cable over the long distance to the amplifier. This approach eliminates most of the signal loss due to speaker cable resistance so the speakers are fed all of the amplifier's power without the need for heavy cables. In cases where speakers and power amplifiers are located far away from the signal source, "balanced line" cables are a wise choice. Doing so can actually save money. The use of stranded wire is highly recommended since it is flexible and less prone to metal fatigue breakage. If an end is nicked while insulation is being stripped for connection, only one or two strands will break and not the entire wire. NEVER use coiled cords for speaker hookup, even in an emergency. Coiled guitar-type cords usually have higher internal resistance than the speakers themselves. This is due to the light-gauge wire used to keep the coil cords flexible. Unfortunately, these types of cord prevent most of the power from reaching the speakers. In high power operation, a coil cord can melt causing a fire hazard and possible damage to the amplifier. As a general rule, both straight and coiled guitar-type connecting cords make poor speaker cables. The SPL-M500 can produce enough power output to damage electronic equipment connected to its output. Besides being capable of destroying speakers, shock and / or fire hazards are also possible. High power amplifiers should always be properly applied and used with care in a clean and dry environment. Be sure to turn on all other equipment before turning on the SPL-M500 power amplifier. This will prevent turn-on "thumps" from the mixer or other pieces of gear that could possibly damage speakers. Likewise, the reverse logic should also be applied -turn OFF the amplifier FIRST -- when shutting down the system. SPEAKER WIRE GAUGE SPEAKER WIRE LENGTH 100'-UP 50'-100' (30.5 m-UP) (15.25-30.5 m) (7.60-15.25 m) 8 10 12 14 16 10 12 12 14 14 16 18 18 18 *25'-50' 14 *16 16 18 18 18 (3.05-7.60 m) (0.00-3.05 m) 10'-25' 0'-10' 2 4 *8 16 SPEAKER IMPEDANCE [z] *Example - If the speaker wire length required is between 25-50 feet (7.60-15.25 meters) and the speaker impedance is 8, the minimum recommended speaker wire gauge is 16. AWG 18 16 14 12 10 8 mm 2 0.83 1.32 2.10 3.32 5.27 8.38 Resistance in per foot (30.5 cm) @ 77º F (25º C) .00651 .00409 .00258 .00162 .00102 .00064 6 The SPL-M500 is timed to turn on the speaker outputs after the amplifier's power supply is fully charged up, thus preventing any turn-on noise. Timing of the amplifier's turn-on circuit is usually sufficient to accommodate all the turn-on anomalies from other pieces of gear in a system, making it acceptable to use a single switched power string in a permanent or semi-permanent application. The SPL-M500 can draw a lot of AC power. Be sure the AC power source for your AC distribution system has adequate current capability. In multiple amplifier installations, a sequential turn-on (either manually or via timed relays) is recommended to avoid a sudden major drain on the AC line. Remember, severe reduction of power line voltages affects the amount of power you can get FROM the amplifier. If you need to run long AC extension cords, make sure their conductors are as large as practical (small gauge number). Just as sm ...