User manual MARTIN AUDIO MA1.3

[. . . ] CONTENTS < 1 2 3 3. 1 3. 2 3. 3 4 4. 1 4. 2 5 5. 1 5. 2 5. 3 5. 4 5. 5 5. 6 5. 7 6 6. 1 6. 2 6. 3 6. 4 7 7. 1 7. 2 7. 3 7. 4 7. 5 8 9 10 11 12 13 14 > PRINT GUIDES CONTENTS (ENGLISH) UNPACKING WARNINGS USER RESPONSIBILITY Speaker damage Shock hazard Radio interference INTRODUCTION Front panel Rear panel INSTALLATION Mounting Cooling Operating voltage Grounding Power consumption Input connections Connecting speakers OPERATION MODES Stereo operation Tandem mono Bridged mono Stereo reverse OPERATION Operation precautions Powering up - Soft start Input attenuators Gain switch Indicators PROTECTION FEATURES DESIGN FEATURES SPECIFICATIONS APPENDIX A MAINTENANCE WARRANTY TECHNICAL SPECIFICATIONS Page No 2 2 3 3 3 3 4 4 5 6 6 6 6 7 7 8 11 11 11 12 12 13 13 13 14 14 14 14 15 16 18 19 20 21 22 MARTIN AUDIO LONDON The Martin Experience Martin Audio ­ MA1. 3 Power Amplifier CONTENTS < > ENGLISH PRINT GUIDES This equipment conforms to the requirements of the EMC Directive 89/336/EEC, amended by 92/31/EEC and 93/68/EEC and the requirements of the Low Voltage Directive 73/23/EEC, amended by 93/68/EEC. Standards Applied EMC Emission Immunity EN55103-1:1996 EN55103-2:1996 EN60065:1993 Electrical Safety 1 UNPACKING Each Martin Audio MA Series amplifier is built to the highest standard and thoroughly inspected before it leaves the factory. After unpacking the unit, examine it carefully for any signs of transit damage and inform your dealer if such damage is found. It is suggested that you retain the original packaging so that the unit can be repackaged at a future date if necessary. Please note that Martin Audio and its distributors cannot accept responsibility for damage to any returned product through the use of non-approved packaging. 2 · · · WARNINGS Do not use this amplifier if the mains cable is damaged. [. . . ] Do not use the remaining XLR and TRS connectors for mixing or other purposes. Both level attenuators are active, allowing you to set different levels for each channel. Never connect either output terminal to ground or in parallel. 6. 3 Bridged mono To bridge the amplifier, depress the Link switch (7) and Phase reverse switch (6). Both channels are then driven by a single signal at either input. You can use any remaining input connectors for linking etc. Do not use the remaining XLR and TRS as input jacks simultaneously for mixing or other purposes. To obtain an output, connect the speaker leads to pin +1 on channel A Speakon to speaker positive terminal and pin +1 on channel B Speakon to speaker negative terminal. Do not connect either of the -1 (negative) pins of the Speakons. Do not connect speakers to channel A or B in the normal manner in bridge mode, as this can cause serious damage. The recommended minimum nominal impedance for bridged mono is 4 ohms (equivalent to driving both channels at 2 ohms). Driving bridged loads of less than 4 ohms may cause a thermal overload. + ­ 2 3 1 + CH A + ­ ­ + I/P LINK ­ 2 3 1 PHASE INVERT + ­ + CH B + ­ ­ Figure 10. Bridge mono connection Both level attenuators must be at the same position. We recommend that you put them in the 0dB (full) position. 12 Martin Audio ­ MA1. 3 Power Amplifier CONTENTS < > ENGLISH PRINT GUIDES 6. 4 Stereo reverse This mode is similar to the Tandem mono mode. Apart from depressing the Link switch, you also depress the Phase reverse switch, as in the Bridge mono. To compensate for that, connect pin +1 on channel B Speakon to speaker negative terminal and pin -1 on channel B to speaker positive terminal. + ­ 2 3 1 + CH A + ­ + ­ I/P LINK 2 3 1 PHASE INVERT + ­ + CH B + ­ ­ + Figure 11. Stereo reverse mode Channel A output is connected as in the normal stereo mode. By having channel A and B operating in opposite polarity, the energy storage in the power supply is more efficient. This means that the amplifier can deliver up to 10% more power than in tandem mono mode. This is significant for signals below 100Hz (sub bass etc. ). 7 OPERATION 7. 1 Operation precautions · Make sure that the power switch is off before making any input or output connections or operating the switches on rear panel. · Make sure that the AC mains is correct and the same as that printed on the rear panel of the amplifier. See pages 6-8 about operating voltage and power consumption. [. . . ] Check that the VHF protection is not activated. If it is, remove possible high frequency oscillations from the relevant input. Fault: The amplifier goes into thermal protection when driven at low level. Check that your loudspeaker has not got a short circuit in its windings, (this can occur when the speaker coil gets warm). [. . . ]