MPA Series Power Amplifiers Owner's Manual Clip Clip -10dB Protect -20dB MPA275 Professional Amplifier -10dB -20dB Signal Present 10 Power Signal Present 10 12 14 8 6 14 12 8 6 18 4 18 4 24 48 0 2 24 2 48 0 1-CHANNEL-2 MPA275 Clip Clip -10dB Protect -20dB MPA400 Professional Amplifier -10dB -20dB Signal Present 10 Power Signal Present 10 12 14 8 6 14 12 8 6 18 4 18 4 24 48 0 2 24 2 48 0 1-CHANNEL-2 MPA400 Clip Clip -10dB Protect -20dB MPA600 Professional Amplifier -10dB -20dB Signal Present 10 Power Signal Present 10 12 14 8 6 14 12 8 6 18 4 18 4 24 48 0 2 24 2 48 0 1-CHANNEL-2 MPA600 MPA750 Professional Amplifier Clip -10dB -20dB Signal Present 10 Clip -10dB Protect -20dB Power Signal Present 10 12 14 8 6 14 12 8 6 18 4 18 4 24 48 0 2 24 2 48 0 1-CHANNEL-2 MPA750 MPA1100 Professional Amplifier Clip -10dB -20dB Signal Present 10 Clip -10dB Protect -20dB Power Signal Present 10 12 14 8 6 14 12 8 6 18 4 18 4 24 48 0 2 24 2 48 0 1-CHANNEL-2 MPA1100 Cautions Rack Mounting Precautions To avoid damage to the amplifier mounting ears and/or rack rails, the amplifier must be supported at all four corners when used in portable racks. Consult JBL Service Dept for availability of Rear Support Brackets. Sicherheitsvorschriften Sicherheitsvorschriften für den Einbau in ein Gestell Um Schäden auf den Befestigungsleisten des Verstärkers und/oder den Gestellschienen zu vermeiden, muß der Verstärker beim Einbau in ein tragbares Gestell an allen vier Ecken gestützt werden. Erkundigen Sie sich bei der JBLKundendienstabteilung nach Stützen für die Rückseite des Verstärkers. Lifting Precautions In order to safely move or install the amplifier, it is recommended that two persons share the weight when lifting and positioning the unit. Sicherheitsvorschriften beim Hochheben Um den Verstärker sicher zu verschieben oder einzubauen, wird empfohlen, das Gewicht des Verstärkers beim Hochheben und Verschieben gleichmäßig auf zwei Personen zu verteilen. VORSICHT UM ELEKTRISCHEN SCHLAG ZU VERMEIDEN, KEINE FINGERN ODER GEGENSTÄNDE IN ÖFFNUNGEN DES GEHÄUSES STECKEN. CAUTION TO AVOID ELECTRIC SHOCK, DO NOT INSERT FINGERS OR OBJECTS INTO ANY OPENINGS IN THE CABINET. WARNING: TO P R E V E N T F I R E O R E L E C T R I C SHOCK, DO NOT EXPOSE THIS EQUIPMENT TO RAIN OR MOISTURE. WARNUNG: ZUR VERMEIDUNG VON FEUER ODER ELEKTRISCHEN SCHLÄGEN DAS GERÄT NICH MIT REGEN ODER FEUCHTIGKEIT IN BERÜHRUNG BRINGEN. Explanation of Graphical Symbols The lightning flash with arrowhead symbol, within an equilateral triangle, is intended to alert the user to the presence of uninsulated "dangerous voltage" within the product's enclosure that may be of sufficient magnitude to constitute a risk of electric shock to humans. The exclamation point within an equilateral triangle is intended to alert the users to the presence of important operating and maintenance (servicing) instructions in the literature accompanying the product. Erklärung der graphischen Symbole Der Blitz mit nach unten zeigendem Pfeil in einem gleichseitigen Dreieck weist den Benutzer auf das Vorhandensein einer unisolierten, "gefährlichen Spannung" im Gehäuse hin, die stark genug sein kann, einer Person einen elektrischen Schlag zu versetzen. Das Ausrufezeichen in einem gleichseitigen Dreieck weist den Benutzer auf nichtige Betriebs - und Wartungsvorschriften in den Beiliegenden Unterlagen des Gerätes hin. CAUTION RISK OF ELECTRIC SHOCK DO NOT OPEN VORSICHT GEFAHR EINES ELEKTRISCHEN SCHLAGES NICHT ÖFFNEN NO USERUM DAS RISIKO EINES ELEKTRISCHEN S C H L A G E S Z U V E R M I N D E R N, A B D E C K U N G N I C H T ENTFERNEN. KEINE BENUTZER BEDIENUNGSTEILE IM INNERN. BEDIENUNG NUR DURCH QUALIFIZIERTES BEDIENUNGSPERSONAL. CAUTION: TO REDUCE THE RISK OF ELECTRIC VORSICHT: SHOCK, DO NOT REMOVE THE COVER. SERVICEABLE PARTS INSIDE. REFER SERVICING TO QUALIFIED SERVICE PERSONNEL. CAUTION RISK OF ELECTRIC SHOCK: OPEN ONLY IF QUALIFIED AS SERVICE PERSONNEL VORSICHT GEFAHR EINES ELEKTRISCHEN SCHLAGES: NUR VON QUALIFIZIERTEM WARTUNGSPERSONAL ZU ÖFFNEN To reiterate the above warnings: servicing instructions are for use by qualified personnel only. To avoid electric shock, do not perform any servicing other than that contained in the Operation Instructions unless you are qualified to do so. Refer all servicing to qualified service personnel Eindrigliche Warnung: Wartungsvorschriften dienen nur der Benutzung durch qualifiziertes Personal. Zur Vermeidung eines elektrischen Schlages keine anderen als die in den Betriebsvorschriften beschriebenen Wartungsarbeiten ausführen, es sei denn, Sie sind dafür qualifiziert. Wartungsarbeiten sind von qualifiziertem Wartungspersonal auszuführen. 1 Table of Contents Cautions .................................................................................................................1 Unit Description ....................................................................................................3 General Information ....................................................................................................3 Open Input ArchitectureTM Slots .................................................................................3 Feature Identification...................................................................................................4 Installation .............................................................................................................5 Inputs ...........................................................................................................................5 Outputs ........................................................................................................................5 Input Connections .......................................................................................................6 Changing XLR Polarity.................................................................................................7 To Parallel the Inputs ..................................................................................................7 Bridged Mono Mode ...................................................................................................8 AC Power Connection .................................................................................................9 Operation .............................................................................................................10 Controls ......................................................................................................................12 Gain Control Lockout ................................................................................................12 Displays......................................................................................................................12 Typical Power Up, Operation, Power Down Behavior...........................................12 Maximum Long-Term Output Power........................................................................14 Protection Circuits......................................................................................................14 Specifications.......................................................................................................16 Power Output Ratings ...............................................................................................17 Troubleshooting ..................................................................................................19 Illustrations Figure 1. Open Input Architecture Slots.....................................................................3 Figure 2. Rear and Front Views of 2-Space High Amplifiers ....................................4 Figure 3. Rear and Front Views of 3-Space High Amplifiers ....................................4 Figure 4. Neutrik Speakon Connector Wiring for Speaker Outputs .........................5 Figure 5. Typical Unbalanced Connection.................................................................6 Figure 6. Portable Balanced System ...........................................................................6 Figure 7. Installed Balanced System ...........................................................................6 Figure 8. Ground Bus Connection..............................................................................6 Figure 9. Jumper Positions for XLR Polarity Reversal................................................7 Figure 10. Switch Settings for Bridged Mono Operation...........................................7 Figure 11. Connection Options of Speaker Load for Bridged Mono ......................8 Figure 12. Speakon Connection Details for Bridged Mono Operation. ...................8 Figure 13. Gain Control Lockout...............................................................................12 Figure 14. LED Displays During Normal Operation ................................................13 Figure 15. LED Displays During Abnormal Operating Conditions .........................13 Tables Table 1. JBL MPA Series AC Power Consumption versus Load Impedance With 110, 115 & 120 V Mains ..............................9 Table 2. JBL MPA Series AC Power Consumption versus Load Impedance With 220, 230 & 240 V Mains.............................10 Table 3. LED Display Operation ...............................................................................11 Table 4. Output Ratings With 110, 115 and 120 V Mains........................................16 Table 5. Output Ratings With 110, 115 and 120 V Mains........................................17 2 Unit Description The MPA275, MPA400, MPA600, MPA750 and MPA1100 are high-efficiency professional power amplifiers, with two independent channels, respectively capable of delivering 275, 400, 600, 750 and 1100 watts into a four ohm load (per channel), and substantially more power into lower impedance loads. Semi-toroidal power transformers (one per channel in the MPA750 and MPA1100) are mounted in each front corner, as close as possible to the rack ears and rails. The rear panels are 16.9 inches behind the front mounting plane, so an extra rack depth allowance (i.e., more than 18 inches) will be needed to clear XLR or Speakon connections. The built-in fan cooling takes air in the rear, exhausting through front vents. Due to the flow-through cooling, amplifiers may be racked with zero clearance in between, which also helps support the weight. Rear support within the rack must be used in portable applications. Open Input ArchitectureTM Slots Provided with each MPA Series amplifier is a standard input module. This module and the upper input cover panel can be removed, permitting future upgrades. Internally, a ribbon cable runs behind both of these "slots." The ribbon cable connects to the rest of the amplifier and carries several levels of DC power, and (for each channel) the input signals, speaker output monitor, muting status, clip activity, thermal status, and power-on status. These signals are provided to support future remote control and monitoring schemes as they become available. The JBL Marketing department will be happy to entertain suggestions for input modules. The "standard input board" which is shipped with each amplifier has balanced XLR and barrier strip inputs, bridging and input-parallel switches, and footprints for passive rolloffs and popular input isolation transformers (more info is available on request). Figure 1. Open Input Architecture Slots. 3 Unit Description 1 2 4 5 3 14 15 CHANNEL 2 OUTPUT 17 19 + 16 CHANNEL 1 OUTPUT ­ BRIDGED MONO PARALLEL STEREO P2 GND P1 + ­ GND ­ + BRIDGE INPUT P2 GND P1 CH 1 DUAL CHANNEL OUTPUT CONNECTOR SENSITIVITY 1 VOLT IMPEDANCE 20K BAL 10K UNBAL STEREO P3 P3 4 OHM MIN PER CH CHANNEL 2 CHANNEL 1 CH 2 + BRIDGED MONO 8 OHM MIN ­ Figure 2. Rear and Front Panel for 2­Space High Models (MPA275, MPA400 & MPA600) 6 8 9 10 11 12 13 7 24 25 Clip 18 27 28 21 26 Clip -10dB 20 23 22 MPA600 Professional Amplifier -10dB -20dB Signal Present 10 Protect -20dB Power Signal Present 10 12 14 8 6 14 12 8 6 18 4 18 4 24 48 0 2 24 2 48 0 1-CHANNEL-2 31 1 2 4 5 3 29 14 30 15 17 19 16 31 CHANNEL 2 OUTPUT ­ BRIDGED MONO + CHANNEL 1 OUTPUT PARALLEL STEREO P2 GND P1 + ­ GND ­ + BRIDGE INPUT P2 GND P1 CH 1 SENSITIVITY 1 VOLT IMPEDANCE 20K BAL 10K UNBAL DUAL CHANNEL P3 P3 OUTPUT CONNECTOR STEREO 4 OHM MIN PER CH CHANNEL 2 CHANNEL 1 CH 2 + BRIDGED MONO 8 OHM MIN ­ Figure 3. Rear and Front Panel for 3­Space High Models (MPA750 and MPA1100) 6 8 9 10 11 12 13 24 7 25 Professional Amplifier 18 27 28 26 21 20 23 22 MPA1100 Clip -10dB -20dB Signal Present 10 Clip -10dB Protect -20dB Power Signal Present 10 12 14 8 6 14 12 8 6 18 4 18 4 24 48 0 2 24 2 48 0 1-CHANNEL-2 31 29 30 31 Rear Panel Features 1. Upper I ...