background image

8

CHAPTER2

         

NOTE:

 For best performance, the AC cable 

voltage drop should not exceed 10 volts, or 

10 percent at 115 volts and 5 percent at 230 volts. 
Make sure that even with the AC voltage drop, the 
AC voltage always stays in the operating windows.

The minimum electrical service amperage required by 
an MJF-212A system is the sum of each loudspeaker’s 

maximum long-term continuous current

. An additional 30 

percent above the minimum amperage is recommended to 
prevent peak voltage drops at the service entry.

ElECTRICAl SAfETy ISSUES

Pay close attention to these important electrical and safety 
issues.

 

 

CAUTION:

 In the unlikely event that the 

circuit breakers on the monitor’s user panel 

trip (the white center buttons pop out), disconnect 
the AC power cable. Do not reset the breakers with 
the AC connected. Contact Meyer Sound for repair 
information.

 

CAUTION: 

The MJF-212A monitor requires 

a grounded connection. Always use a 

grounded outlet and plug.

 

CAUTION: 

Do not use a ground-lifting 

adapter or cut the AC cable ground pin.

 

CAUTION: 

Do not exceed the current 

capability of the monitor’s 20-amp AC 

connector. When looping, always take into account 
the current draw of all loudspeakers on the circuit, 

including

 the first unit. 

 

CAUTION: 

Make sure that the power plug 

is appropriate for the AC power at the site 

where you will operate the MJF-212A monitor. In 
addition, the connector must be rated for the total 
load of 

all

 MJF-212A loudspeakers looped to the 

same power plug.

Summary of Contents for MJF-212A

Page 1: ...OPERATING INSTRUCTIONS ULTRAseries MJF 212A High Power Stage Monitor Keep these important operating instructions Check www meyersound com for updates...

Page 2: ...to 4600 m 15 000ft Non operating altitude to 6300 m 25 000ft Shock 30 g 11 msec half sine on each of 6 sides Vibration 10 Hz to 55 Hz 0 010 peak to peak excursion 2007 Meyer Sound All rights reserved...

Page 3: ...d by Meyer Sound or sold with the loudspeaker Handles are for carrying only 13 Unplug this loudspeaker during lightning storms or when unused for long periods of time 14 Refer all servicing to qualifi...

Page 4: ...ages auf ein Minimum zu reduzieren den Lautsprecher vom Stromnetz trennen bevor ggf ein Audio Schnittstellensign alkabel angeschlossen wird Das Netzkabel erst nach Herstellung aller Signalverbindungen...

Page 5: ...Electrical Safety Issues 8 CHAPTER 3 Amplification and Audio 9 Audio Input 9 Amplification and Protection Circuitry 9 MJF 212A Interconnections 10 Cabling 10 The Limiting System 10 Low Frequency Limi...

Page 6: ...vi...

Page 7: ...tory installed VEAM Connector Appendix B Specifications and Dimensional Drawings provides detailed acoustic and electrical specifications for the MJF 212A monitor along with detailed dimensional drawi...

Page 8: ...INTRODUCTION...

Page 9: ...m concerts as well as corporate AV applications and clubs The MJF 212A produces a peak output of 139 dB SPL with exceptionally flat phase and frequency response The cabinet is constructed from premium...

Page 10: ...sing package also incorporates Meyer Sound s Intelligent AC power supply which automatically adjusts for common line voltage worldwide and provides both soft turn on and transient protection The MJF 2...

Page 11: ...distribution system with the load between loudspeakers distributed among the three phases and all of the loudspeakers connected to common neutral and earth ground points Figure 2 1 A sample AC power...

Page 12: ...For units shipped with the VEAM all in one multipin connector please refer to Appendix A for AC Power pin out Caution When creating AC cables and distribution systems it is important to preserve AC l...

Page 13: ...o either low or high voltage its power supply automatically turns on again after three seconds if the voltage has returned to either normal operating window If the MJF 212A stage monitor does not turn...

Page 14: ...hat the circuit breakers on the monitor s user panel trip the white center buttons pop out disconnect the AC power cable Do not reset the breakers with the AC connected Contact Meyer Sound for repair...

Page 15: ...loudspeaker If the noise stops most likely the problem is not with the loudspeaker Check the audio cable source and AC power to pinpoint the problem Audio signals can be daisy chained using the Loop o...

Page 16: ...or s left and right 12 inch cone drivers are powered by separate amplifier channels each with a detector but routed to one limiter The lower limit LED on the user panel indicates limiting activity for...

Page 17: ...he temperature of the heatsink reaches 75 C 167 F the On Temp LED on the rear panel turns from green On to red Temp The unit continues to operate normally even if the On Temp LED is red but this is an...

Page 18: ...12 CHAPTER 3...

Page 19: ...his information is permanently retained on each RMS communication board and in the computer RMS database until you modify it Loudspeaker View labels can be modified at any time allowing you to customi...

Page 20: ...e Service Button the card will be decommissioned from the network and the red Service LED will blink Activity LED Green When the loudspeaker has been commissioned the Activity LED will flash continuou...

Page 21: ...neutral blue Figure A 1 VEAM multipin connector power pin out For complete wiring conventions and pin outs for AC audio and RMS connections please refer to the Meyer Sound document VEAM Cable Wiring...

Page 22: ...16 APPENDIX A...

Page 23: ...00 Hz Note At this frequency the transducers produce equal sound pressure levels TRANSDUCERS Low low mid frequency Two high power 12 cone drivers with neodymium magnets Nominal impedance 2 Voice coil...

Page 24: ...W 1 x 275 W 2550 W peak Note Amplifier wattage rating based on the maximum unclipped burst sine wave rms voltage that the amplifier will produce for at least 0 5 seconds into the nominal load impedan...

Page 25: ...23mm 40 13 70 348mm 23 00 584mm 40 PHYSICAL Enclosure Premium birch plywood Finish Black textured Protective grille Powder coated hex stamped steel black mesh Dimensions 27 07 w x 16 11 h x 23 00 d 68...

Page 26: ...20 APPENDIX B...

Page 27: ......

Page 28: ...2007 Meyer Sound Laboratories Inc 05 157 005 02 A Meyer Sound Laboratories Inc 2832 San Pablo Avenue Berkeley CA 94702 www meyersound com T 1 510 486 1166 F 1 510 486 8356...

Reviews: