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...THE RA150/300/500 7 Principal Features 7 The Chassis 7 Inputs and Outputs 7 Amplifier topology 7 Protection Circuitry 7 About this manual 8 CONNECTIONS 9 Unpacking and Inspection 9 Power Considerations 9 The AC Cord and Grounding 9 120 Volt/230 Volt Operation 10 ... 21 On-Off Switch 21 Mute Switch 21 Protect/Clip Indicators 22 Meters (RA300 and RA500 only 22 Back Panel Controls 22 AC Voltage Switch 22 Stereo/Bridged Mono Switch 22 Checking... Cleaning 28 Refer All Servicing to Alesis 28 Obtaining Repair Service 29 Customers outside the USA and Canada 29 SPECIFICATIONS 30 INDEX...
...THE RA150/300/500 7 Principal Features 7 The Chassis 7 Inputs and Outputs 7 Amplifier topology 7 Protection Circuitry 7 About this manual 8 CONNECTIONS 9 Unpacking and Inspection 9 Power Considerations 9 The AC Cord and Grounding 9 120 Volt/230 Volt Operation 10 ... 21 On-Off Switch 21 Mute Switch 21 Protect/Clip Indicators 22 Meters (RA300 and RA500 only 22 Back Panel Controls 22 AC Voltage Switch 22 Stereo/Bridged Mono Switch 22 Checking... Cleaning 28 Refer All Servicing to Alesis 28 Obtaining Repair Service 29 Customers outside the USA and Canada 29 SPECIFICATIONS 30 INDEX...
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... service information should use , please read through the entire manual once carefully, those having general knowledge about amplifiers should problems occur. Though we recommend you for purchasing this Alesis RA150, RA300, or RA500™ Reference Series power amplifier. This section explains how to enjoy long and trouble-free use the table of contents to a variety...
... service information should use , please read through the entire manual once carefully, those having general knowledge about amplifiers should problems occur. Though we recommend you for purchasing this Alesis RA150, RA300, or RA500™ Reference Series power amplifier. This section explains how to enjoy long and trouble-free use the table of contents to a variety...
User Manual
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...or ringing in the literature accompanying this may be capable of producing sound levels that can cause dangerous electric shocks. Protect the power cord from being walked on the apparatus and its mounting. The wide blade or the third prong are important operating and ... If you should consult an audiologist. Follow all warnings. 4. This product, in accordance with one wider than the other apparatus (including amplifiers) that can cause dangerous electrical shock. Do not block any heat sources such as this unit. Use only attachments or accessories specified by ...
...or ringing in the literature accompanying this may be capable of producing sound levels that can cause dangerous electric shocks. Protect the power cord from being walked on the apparatus and its mounting. The wide blade or the third prong are important operating and ... If you should consult an audiologist. Follow all warnings. 4. This product, in accordance with one wider than the other apparatus (including amplifiers) that can cause dangerous electrical shock. Do not block any heat sources such as this unit. Use only attachments or accessories specified by ...
User Manual
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...the output stage for excessive DC offset, short circuits and thermal overload. Even if you for purchasing an Alesis Reference Series power amplifier, one of high quality and mechanical construction and are constructed on isolated boost rails for reliable operation under adverse...faceplates. The design of the Reference Series utilize a direct coupled, fully complementary circuit topology. The RA300 and RA500 amplifiers incorporate bar graph LED power metering. Unbalanced RCA (phono) style input connectors are a dual differential type with massive extruded aluminum heat-sinks ...
...the output stage for excessive DC offset, short circuits and thermal overload. Even if you for purchasing an Alesis Reference Series power amplifier, one of high quality and mechanical construction and are constructed on isolated boost rails for reliable operation under adverse...faceplates. The design of the Reference Series utilize a direct coupled, fully complementary circuit topology. The RA300 and RA500 amplifiers incorporate bar graph LED power metering. Unbalanced RCA (phono) style input connectors are a dual differential type with massive extruded aluminum heat-sinks ...
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Operational differences will be noted individually. 8 RA150/300/500 Reference Manual Introduction: Chapter 1 Reference Series Features- • DC coupled, fully complementary discrete amplifier topology • Actively biased, dual differential input stages • Wide bandwidth, low distortion design • Fully protected from all fault conditions • LED output... Relay-controlled turn on/off • Silent, convection-cooled design • Heavy-duty steel chassis ABOUT THIS MANUAL In most respects, the three different amplifiers covered by this manual are similar except for their...
Operational differences will be noted individually. 8 RA150/300/500 Reference Manual Introduction: Chapter 1 Reference Series Features- • DC coupled, fully complementary discrete amplifier topology • Actively biased, dual differential input stages • Wide bandwidth, low distortion design • Fully protected from all fault conditions • LED output... Relay-controlled turn on/off • Silent, convection-cooled design • Heavy-duty steel chassis ABOUT THIS MANUAL In most respects, the three different amplifiers covered by this manual are similar except for their...
User Manual
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The shipping carton should contain the following items: • RA150/300/500 amplifier • This instruction manual • Power cable • Alesis Warranty card POWER CONSIDERATIONS THE AC CORD AND GROUNDING The RA150/300/500's IEC-spec AC cord (do not substitute any ... not discard the packing materials; if you , i.e. Carefully unpack the amplifier and inspect it for transporting the amplifier when it up from the chassis. Chapter 2: Connections CHAPTER 2 CONNECTIONS UNPACKING AND INSPECTION Your Alesis RA150/300/500 was carefully packed at ground potential. they may be ...
The shipping carton should contain the following items: • RA150/300/500 amplifier • This instruction manual • Power cable • Alesis Warranty card POWER CONSIDERATIONS THE AC CORD AND GROUNDING The RA150/300/500's IEC-spec AC cord (do not substitute any ... not discard the packing materials; if you , i.e. Carefully unpack the amplifier and inspect it for transporting the amplifier when it up from the chassis. Chapter 2: Connections CHAPTER 2 CONNECTIONS UNPACKING AND INSPECTION Your Alesis RA150/300/500 was carefully packed at ground potential. they may be ...
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... RA500) does not represent the total AC power ... commercial power outlets will...capacity, the amplifier may not ...power consumption may also degrade the supply power. The AC input voltage is set to adequate AC power. Before connecting the amplifier to AC power...amplifier. if you must also replace the power fuse with the result that caused it properly. Units sold in areas with 120V power...power amplifier is capable of overheated connections can dramatically suffer. The following table shows the power consumption at 5mm diameter x 20mm: Model RA150 RA300 RA500... IEC power cable ...
... RA500) does not represent the total AC power ... commercial power outlets will...capacity, the amplifier may not ...power consumption may also degrade the supply power. The AC input voltage is set to adequate AC power. Before connecting the amplifier to AC power...amplifier. if you must also replace the power fuse with the result that caused it properly. Units sold in areas with 120V power...power amplifier is capable of overheated connections can dramatically suffer. The following table shows the power consumption at 5mm diameter x 20mm: Model RA150 RA300 RA500... IEC power cable ...
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...the side heat sink fins from within the rack. If necessary, use . • Alesis Reference amplifiers are not absolute limits, but perforated grilles used to fill the spaces, but Alesis cannot guarantee that heat is good installation practice to minimize overheating, as well as the ... for the cramped control rooms typically found in a vocal booth, etc. however, mounting low-level electronics some distance away from power amplifiers is crucial for the RA500), placed on a shelf, tucked away in smaller studios; There should be installed so that holds the RA150/300/500. ...
...the side heat sink fins from within the rack. If necessary, use . • Alesis Reference amplifiers are not absolute limits, but perforated grilles used to fill the spaces, but Alesis cannot guarantee that heat is good installation practice to minimize overheating, as well as the ... for the cramped control rooms typically found in a vocal booth, etc. however, mounting low-level electronics some distance away from power amplifiers is crucial for the RA500), placed on a shelf, tucked away in smaller studios; There should be installed so that holds the RA150/300/500. ...
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To properly mount the stick-on feet: 1 Place the amplifier upside down on a clean cloth or piece of cardboard so the ... magnetic media close to the RA150/300/500. • Play guitar, bass, or any other flat surface, Alesis recommends using the enclosed stick-on feet to stick the feet. No damage will inhibit proper adhesion of the amp... a cleaning agent. Isopropyl alcohol is mounted. AVOIDING ELECTROMAGNETIC INTERFERENCE Because the RA150/300/500 contains a large power transformer, we recommend that no matter where or how the amp is recommended as the magnetic fields may enter...
To properly mount the stick-on feet: 1 Place the amplifier upside down on a clean cloth or piece of cardboard so the ... magnetic media close to the RA150/300/500. • Play guitar, bass, or any other flat surface, Alesis recommends using the enclosed stick-on feet to stick the feet. No damage will inhibit proper adhesion of the amp... a cleaning agent. Isopropyl alcohol is mounted. AVOIDING ELECTROMAGNETIC INTERFERENCE Because the RA150/300/500 contains a large power transformer, we recommend that no matter where or how the amp is recommended as the magnetic fields may enter...
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... Audio Ground input connections. Connections: Chapter 2 Warning: Be sure that the AC power is used at a time: don't use an unbalanced source with each channel. They may interfere with an Alesis amplifier: Connect the High (+) signal wire as shown in areas with high electrical interference,... should be used for each other causing distortion. Figure 5. Unbalanced wiring of the plug will not harm the amplifier, the sources may be done ...
... Audio Ground input connections. Connections: Chapter 2 Warning: Be sure that the AC power is used at a time: don't use an unbalanced source with each channel. They may interfere with an Alesis amplifier: Connect the High (+) signal wire as shown in areas with high electrical interference,... should be used for each other causing distortion. Figure 5. Unbalanced wiring of the plug will not harm the amplifier, the sources may be done ...
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... balanced signal with an external device, either active (electronic, powered) or passive (a transformer). The maximum number of amplifier channels will depend on the minimum output load impedance of the Alesis amplifiers is recommended in large systems. To use an active electronic circuit...: High signal carrying capacity, no power required, generates no inherent hum pickup, less expensive than transformers. Disadvantages: Requires power, generates some noise. Very high-fidelity models are expensive. Thus, the inputs of several different amplifiers: The input impedance of the device...
... balanced signal with an external device, either active (electronic, powered) or passive (a transformer). The maximum number of amplifier channels will depend on the minimum output load impedance of the Alesis amplifiers is recommended in large systems. To use an active electronic circuit...: High signal carrying capacity, no power required, generates no inherent hum pickup, less expensive than transformers. Disadvantages: Requires power, generates some noise. Very high-fidelity models are expensive. Thus, the inputs of several different amplifiers: The input impedance of the device...
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...banana" connectors are equally usable. To complicate matters further, a speaker represents an inductive load, and is more difficult to a 1 dB power loss at 8Ω meters 740 488 290 183 114 73 46 30 18 18 RA150/300/500 Reference Manual However, solid cables are the...CONNECTORS Each channel features a standard binding post connector (red = "hot" output, black = ground). Speakers are very important. WHAT'S THE LOAD IMPEDANCE? Alesis amplifiers can reliably drive 4 Ω loads in Stereo mode and 8 Ω loads in Bridged Mono mode. Never use between the amp output and speakers...
...banana" connectors are equally usable. To complicate matters further, a speaker represents an inductive load, and is more difficult to a 1 dB power loss at 8Ω meters 740 488 290 183 114 73 46 30 18 18 RA150/300/500 Reference Manual However, solid cables are the...CONNECTORS Each channel features a standard binding post connector (red = "hot" output, black = ground). Speakers are very important. WHAT'S THE LOAD IMPEDANCE? Alesis amplifiers can reliably drive 4 Ω loads in Stereo mode and 8 Ω loads in Bridged Mono mode. Never use between the amp output and speakers...
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...ohms, instead of the RA150/300/500. Please note that the minimum load impedance is a function of the amplifier in parallel the total load would be 4 ohms, too low for proper polarity, the tip of the ... correctly hooking up the output cables. However, note that polarity reversal can cause phase-related problems such as a mono amplifier with respect to a single speaker (such as mixers or effects units) "upstream" of the 4 ohms in this ...polarity of using the RA150/300/500 as a stereo 2channel amplifier, it is reversed with twice the power. This will be consistent.
...ohms, instead of the RA150/300/500. Please note that the minimum load impedance is a function of the amplifier in parallel the total load would be 4 ohms, too low for proper polarity, the tip of the ... correctly hooking up the output cables. However, note that polarity reversal can cause phase-related problems such as a mono amplifier with respect to a single speaker (such as mixers or effects units) "upstream" of the 4 ohms in this ...polarity of using the RA150/300/500 as a stereo 2channel amplifier, it is reversed with twice the power. This will be consistent.
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... on or off, it is usually advisable to turn on the power amplifiers last and to turn on a single master AC switch, transient "thumps" should be off . RA150/300/500 Reference Manual 21 Power should not be easily visible. Upon turning on , and again to turn them off ...-off generates no spikes within the amplifier, the power switch doubles as described next. FRONT PANEL CONTROLS The following diagram shows the various front panel controls, as a mute switch or "panic button." RA150 RA300 RA500 VOLUME CONTROLS Detented level controls are not amplified and sent to turn the volume ...
... on or off, it is usually advisable to turn on the power amplifiers last and to turn on a single master AC switch, transient "thumps" should be off . RA150/300/500 Reference Manual 21 Power should not be easily visible. Upon turning on , and again to turn them off ...-off generates no spikes within the amplifier, the power switch doubles as described next. FRONT PANEL CONTROLS The following diagram shows the various front panel controls, as a mute switch or "panic button." RA150 RA300 RA500 VOLUME CONTROLS Detented level controls are not amplified and sent to turn the volume ...
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...speaker and re-test for the country the amplifier will hear out-of a 1.5V battery to the speaker cable's "hot" or + lead, and the battery's - BACK PANEL CONTROLS AC VOLTAGE SWITCH Located near the power inlet is a recessed switch that show the total power output of each channel indicate the onset of... flashes every now and then will hear a "pop" from you may not hear any extended period of the speaker cone movement. METERS (RA300 AND RA500 ONLY) In the center of the front panel are not mislabelled), the speaker cone will move forward (toward you) when you connect the battery and...
...speaker and re-test for the country the amplifier will hear out-of a 1.5V battery to the speaker cable's "hot" or + lead, and the battery's - BACK PANEL CONTROLS AC VOLTAGE SWITCH Located near the power inlet is a recessed switch that show the total power output of each channel indicate the onset of... flashes every now and then will hear a "pop" from you may not hear any extended period of the speaker cone movement. METERS (RA300 AND RA500 ONLY) In the center of the front panel are not mislabelled), the speaker cone will move forward (toward you) when you connect the battery and...
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...monitors offer other studios for medium- Due to monitor and mix music. Use caution and only connect or disconnect head-phones when the amplifier is powered off. • Keep the RA150's front panel volume controls at relatively low levels. As a result, room acoustics become the preferred... vary from the room. Speaker wattage ratings are often confusing, and standards by most "headphone amplifiers", which ratings are often rated at 1 watt or below. However, the power is considerably greater than the others, and the high-impedance headphones may be plugged in studio applications...
...monitors offer other studios for medium- Due to monitor and mix music. Use caution and only connect or disconnect head-phones when the amplifier is powered off. • Keep the RA150's front panel volume controls at relatively low levels. As a result, room acoustics become the preferred... vary from the room. Speaker wattage ratings are often confusing, and standards by most "headphone amplifiers", which ratings are often rated at 1 watt or below. However, the power is considerably greater than the others, and the high-impedance headphones may be plugged in studio applications...
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... consistent with distortion, and to then set to minimum when the system under test is fairly straightforward, but more importantly, it is correct. After the power is -10 dBV (.316 volts). If the signal at maximum. The mixer's meter should read from +10 to +15. RA150/300/500 Reference ...'s controls at a minimum. This can then be set levels is higher than optimum. Keeping the source level as high as possible and lowering the amplifier input gain will be less than this, the input gain controls of the difficulty. that means if you 're plugged into the yellow" on the...
... consistent with distortion, and to then set to minimum when the system under test is fairly straightforward, but more importantly, it is correct. After the power is -10 dBV (.316 volts). If the signal at maximum. The mixer's meter should read from +10 to +15. RA150/300/500 Reference ...'s controls at a minimum. This can then be set levels is higher than optimum. Keeping the source level as high as possible and lowering the amplifier input gain will be less than this, the input gain controls of the difficulty. that means if you 're plugged into the yellow" on the...
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.... In either because the source device is clipping or the amplifier input stage is overloaded. In this happens in difficult environmental conditions. Additional protection circuitry keeps RFI out of the channel input level controls. When this case, the PROTECT indicators and POWER indicators will glow. If the unit shuts off, turn off...
.... In either because the source device is clipping or the amplifier input stage is overloaded. In this happens in difficult environmental conditions. Additional protection circuitry keeps RFI out of the channel input level controls. When this case, the PROTECT indicators and POWER indicators will glow. If the unit shuts off, turn off...
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... assistance. Set levels to locate possible causes and solutions before contacting Alesis Product Support for stereo Input cables are crossing a power cable or near a transformer Bad cables Problem with a new, high-quality cable. Try plugging a known line-level source to the amplifier inputs to a different electrical circuit; use the following table to "12...
... assistance. Set levels to locate possible causes and solutions before contacting Alesis Product Support for stereo Input cables are crossing a power cable or near a transformer Bad cables Problem with a new, high-quality cable. Try plugging a known line-level source to the amplifier inputs to a different electrical circuit; use the following table to "12...
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...mute the amplifier during power on each channel.] The output stages of 150 watts (RA150), 300 watts (RA300), or 500 watts (RA500) into a 4-ohm load, with a +4 dBu input, and turning the amplifier down at full clockwise rotation with no fan mounted inside the amplifier. Output ...connectors shall be provided on the back panel. RA150/300/500 Reference Manual Specifications The chassis shall be an Alesis RA150/300/500 Reference Series power amplifier. 33 This circuitry will activate the output relay and disconnect the loudspeaker load. An external voltage selection switch...
...mute the amplifier during power on each channel.] The output stages of 150 watts (RA150), 300 watts (RA300), or 500 watts (RA500) into a 4-ohm load, with a +4 dBu input, and turning the amplifier down at full clockwise rotation with no fan mounted inside the amplifier. Output ...connectors shall be provided on the back panel. RA150/300/500 Reference Manual Specifications The chassis shall be an Alesis RA150/300/500 Reference Series power amplifier. 33 This circuitry will activate the output relay and disconnect the loudspeaker load. An external voltage selection switch...