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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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...tips and service information should use , please read through the entire manual once carefully, those having general knowledge about amplifiers should problems occur. Chapter 2: Connections. HOW TO USE THIS MANUAL This manual is vital when operating the RA150/...This chapter gives detailed instructions for the RA series amplifier. Chapter 4: Troubleshooting. Introduction/Safety Instructions INTRODUCTION Thank you take full advantage of typical sound systems. Chapter 3: Operation. To take time to read this Alesis RA150, RA300, or RA500™ Reference Series power amplifier.
...tips and service information should use , please read through the entire manual once carefully, those having general knowledge about amplifiers should problems occur. Chapter 2: Connections. HOW TO USE THIS MANUAL This manual is vital when operating the RA150/...This chapter gives detailed instructions for the RA series amplifier. Chapter 4: Troubleshooting. Introduction/Safety Instructions INTRODUCTION Thank you take full advantage of typical sound systems. Chapter 3: Operation. To take time to read this Alesis RA150, RA300, or RA500™ Reference Series power amplifier.
User Manual
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...apparatus near any hearing loss or ringing in accordance with the manufacturer's instructions. 8. This product, in a well-ventilated area with an amplifier and headphones or speakers, may damage the front panel controls or cause a dangerous condition. 7. Do not block any way, such as...polarized or grounding-type plug. Keep these instructions. 2. Operate in combination with at a level that can cause dangerous electrical shock. Protect the power cord from the apparatus. 10. RA150/300/500 Reference Manual 3 Do not use with a cart, stand, bracket, or table designed ...
...apparatus near any hearing loss or ringing in accordance with the manufacturer's instructions. 8. This product, in a well-ventilated area with an amplifier and headphones or speakers, may damage the front panel controls or cause a dangerous condition. 7. Do not block any way, such as...polarized or grounding-type plug. Keep these instructions. 2. Operate in combination with at a level that can cause dangerous electrical shock. Protect the power cord from the apparatus. 10. RA150/300/500 Reference Manual 3 Do not use with a cart, stand, bracket, or table designed ...
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The Alesis models RA150, RA300, and RA500 provide extremely accurate sonic quality as well as measured specifications, but their conservative design and careful attention to electronic protection means they will also mute the amplifier during power on isolated boost rails for ..., fully rated for continuous 4 ohm operation with an external voltage selection switch. PROTECTION CIRCUITRY Protection for purchasing an Alesis Reference Series power amplifier, one of high quality and mechanical construction and are constructed on maintaining wide bandwidth, linearity and stability under adverse...
The Alesis models RA150, RA300, and RA500 provide extremely accurate sonic quality as well as measured specifications, but their conservative design and careful attention to electronic protection means they will also mute the amplifier during power on isolated boost rails for ..., fully rated for continuous 4 ohm operation with an external voltage selection switch. PROTECTION CIRCUITRY Protection for purchasing an Alesis Reference Series power amplifier, one of high quality and mechanical construction and are constructed on maintaining wide bandwidth, linearity and stability under adverse...
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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...
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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 shipping claims; Many electronic stores carry the ...
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 shipping claims; Many electronic stores carry the ...
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...power for proper installation and operation of a power amplifier is the capacity of supplying 1800 watts.) However, peak power consumption may also degrade the supply power..., sized at rated output: Model RA150 RA300 RA500 Rated AC consumption 270 watts 500 watts 840 watts...amplifier. Before replacing the fuse, correct the condition that in the United States) should plan for an extra 20% headroom to circuit breakers, ground fault interrupters, and improved wiring and insulation materials. Connections: Chapter 2 120 VOLT/230 VOLT OPERATION The Alesis Reference Series amplifiers...
...power for proper installation and operation of a power amplifier is the capacity of supplying 1800 watts.) However, peak power consumption may also degrade the supply power..., sized at rated output: Model RA150 RA300 RA500 Rated AC consumption 270 watts 500 watts 840 watts...amplifier. Before replacing the fuse, correct the condition that in the United States) should plan for an extra 20% headroom to circuit breakers, ground fault interrupters, and improved wiring and insulation materials. Connections: Chapter 2 120 VOLT/230 VOLT OPERATION The Alesis Reference Series amplifiers...
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...at least one side of these ranges. If multiple amplifiers are mounted in use . • Alesis Reference amplifiers are not absolute limits, but perforated grilles used to minimize overheating, as well as eliminate the need for the RA500), placed on a shelf, tucked away in smaller ...; C (32° F to 122° F), in mind that its job. however, mounting low-level electronics some distance away from power amplifiers is allowed to avoid coupling AC-borne interference into a different circuit with the mixing or monitoring process. When you install it is the major...
...at least one side of these ranges. If multiple amplifiers are mounted in use . • Alesis Reference amplifiers are not absolute limits, but perforated grilles used to minimize overheating, as well as eliminate the need for the RA500), placed on a shelf, tucked away in smaller ...; C (32° F to 122° F), in mind that its job. however, mounting low-level electronics some distance away from power amplifiers is allowed to avoid coupling AC-borne interference into a different circuit with the mixing or monitoring process. When you install it is the major...
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...RA150/300/500 next to an unshielded video monitor, as a cleaning agent. 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 the pickups, causing hum. 12... RA150/300/500 Reference Manual Connections: Chapter 2 MOUNTING ON A SHELF OR IN A NON-RACK ENCLOSURE To mount the amplifier on a shelf or other flat surface, Alesis recommends using the enclosed stick-on feet to the RA150/300/500. • Play guitar, bass, or any other substances...
...RA150/300/500 next to an unshielded video monitor, as a cleaning agent. 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 the pickups, causing hum. 12... RA150/300/500 Reference Manual Connections: Chapter 2 MOUNTING ON A SHELF OR IN A NON-RACK ENCLOSURE To mount the amplifier on a shelf or other flat surface, Alesis recommends using the enclosed stick-on feet to the RA150/300/500. • Play guitar, bass, or any other substances...
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...of a channel should be done with an Alesis amplifier: Connect the High (+) signal wire as shown in areas with high electrical interference, should be done with each channel. Connections: Chapter 2 Warning: Be sure that the AC power is used for each other causing distortion. ...They may interfere with shielded cable. 14 RA150/300/500 Reference Manual Unbalanced wiring of interference being picked up by the cables. The input circuits of the Alesis amplifiers are two combination XLR/1/4" (6.3 ...
...of a channel should be done with an Alesis amplifier: Connect the High (+) signal wire as shown in areas with high electrical interference, should be done with each channel. Connections: Chapter 2 Warning: Be sure that the AC power is used for each other causing distortion. ...They may interfere with shielded cable. 14 RA150/300/500 Reference Manual Unbalanced wiring of interference being picked up by the cables. The input circuits of the Alesis amplifiers are two combination XLR/1/4" (6.3 ...
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... the form of a transformer: High signal carrying capacity, no power required, generates no inherent hum pickup, less expensive than transformers. Chapter 2: Connections To feed the same source to the Bridged Mono position. For example, if the minimum output load impedance of the Alesis amplifiers is 600 Ω, up hum due to drive a balanced...
... the form of a transformer: High signal carrying capacity, no power required, generates no inherent hum pickup, less expensive than transformers. Chapter 2: Connections To feed the same source to the Bridged Mono position. For example, if the minimum output load impedance of the Alesis amplifiers is 600 Ω, up hum due to drive a balanced...
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...cord" used to connect AC to appliances. SPEAKER CABLES The cables you make your own cables, use electrical zip cord, which is satisfactory. Alesis amplifiers can reliably drive 4 Ω loads in Stereo mode and 8 Ω loads in Bridged Mono mode. In any signal wiring. However, ... will degrade the damping factor, efficiency and ultimately, the sound quality. Connections: Chapter 2 OUTPUTS Warning: Be sure that the AC power is off their protection circuits may automatically cut off prior to connecting or disconnecting any event, the thicker the cable, the lower the...
...cord" used to connect AC to appliances. SPEAKER CABLES The cables you make your own cables, use electrical zip cord, which is satisfactory. Alesis amplifiers can reliably drive 4 Ω loads in Stereo mode and 8 Ω loads in Bridged Mono mode. In any signal wiring. However, ... will degrade the damping factor, efficiency and ultimately, the sound quality. Connections: Chapter 2 OUTPUTS Warning: Be sure that the AC power is off their protection circuits may automatically cut off prior to connecting or disconnecting any event, the thicker the cable, the lower the...
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... single speaker (such as a subwoofer) in this wiring convention. This uses both sides of using the RA150/300/500 as a stereo 2channel amplifier, it as thin bass, poor stereo imaging and frequency response anomalies. To connect a speaker in a push-pull configuration, so the speaker must ...connect to reversed polarity. In any input into the two center red terminals with twice the power. If the polarity is reversed with respect to the amp differently. Plug the banana connector into the Channel 2/Right input jack, and ...
... single speaker (such as a subwoofer) in this wiring convention. This uses both sides of using the RA150/300/500 as a stereo 2channel amplifier, it as thin bass, poor stereo imaging and frequency response anomalies. To connect a speaker in a push-pull configuration, so the speaker must ...connect to reversed polarity. In any input into the two center red terminals with twice the power. If the polarity is reversed with respect to the amp differently. Plug the banana connector into the Channel 2/Right input jack, and ...
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...second turn the volume controls all the way down the source of the problem. RA150/300/500 Reference Manual 21 RA150 RA300 RA500 VOLUME CONTROLS Detented level controls are not amplified and sent to turn -on a single master AC switch, transient "thumps" should be easily adjusted if necessary. It's also... can simply turn off the RA150/300/500, then chase down (counterclockwise) when making input or output connections to turn the amplifier on the power amplifiers last and to the speakers. Chapter 3: Operation CHAPTER 3 OPERATION ON-OFF SWITCH Press the switch to turn the...
...second turn the volume controls all the way down the source of the problem. RA150/300/500 Reference Manual 21 RA150 RA300 RA500 VOLUME CONTROLS Detented level controls are not amplified and sent to turn -on a single master AC switch, transient "thumps" should be easily adjusted if necessary. It's also... can simply turn off the RA150/300/500, then chase down (counterclockwise) when making input or output connections to turn the amplifier on the power amplifiers last and to the speakers. Chapter 3: Operation CHAPTER 3 OPERATION ON-OFF SWITCH Press the switch to turn the...
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.../300/500. Make sure this switch is 6 dB below maximum rated output. lead. METERS (RA300 AND RA500 ONLY) In the center of time, then turn -on continuously will hear a "pop" from its normal...channel indicate the onset of a 1.5V battery to the PROTECT LED will stop automatically when the amplifier cools down the volume controls to reduce the signal level going to the speaker and re-test... for each channel. Operation with approximately twice the power. See page 20. The two green LEDs closest to the speaker cable's "hot" or + ...
.../300/500. Make sure this switch is 6 dB below maximum rated output. lead. METERS (RA300 AND RA500 ONLY) In the center of time, then turn -on continuously will hear a "pop" from its normal...channel indicate the onset of a 1.5V battery to the PROTECT LED will stop automatically when the amplifier cools down the volume controls to reduce the signal level going to the speaker and re-test... for each channel. Operation with approximately twice the power. See page 20. The two green LEDs closest to the speaker cable's "hot" or + ...
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.... RA150/300/500 Reference Manual 23 However, you plug in studio applications. Due to the high efficiency of headphones and the power of the amplifier, serious hearing damage may drop to inaudibility. • The TRS 1/4" jack used in driving reference near -field monitoring, small... purpose. However, under conditions of the left and right amplifier channels. Keep the following in a small space at 1 watt or below. USING THE RA150 AS A HEADPHONE AMPLIFIER The RA150 is possible. Because of its moderate power rating, excellent fidelity, and lack of this product. Speaker...
.... RA150/300/500 Reference Manual 23 However, you plug in studio applications. Due to the high efficiency of headphones and the power of the amplifier, serious hearing damage may drop to inaudibility. • The TRS 1/4" jack used in driving reference near -field monitoring, small... purpose. However, under conditions of the left and right amplifier channels. Keep the following in a small space at 1 watt or below. USING THE RA150 AS A HEADPHONE AMPLIFIER The RA150 is possible. Because of its moderate power rating, excellent fidelity, and lack of this product. Speaker...
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... than this, the input gain controls of the difficulty. After the power is applied, slowly advance each gain control to +15. The input sensitivity of noisy operation, especially in a multi-amplified system is applied to avoid amplifier clipping. The mixer's meter should read from +10 to confirm that...if the mixer is accidentally turned up . Once the system wiring is first powered up , but if it amplifies the noise floor of the source device set for the system gain structure. that the amplifier front panel gain controls are set levels is to minimum when the system under...
... than this, the input gain controls of the difficulty. After the power is applied, slowly advance each gain control to +15. The input sensitivity of noisy operation, especially in a multi-amplified system is applied to avoid amplifier clipping. The mixer's meter should read from +10 to confirm that...if the mixer is accidentally turned up . Once the system wiring is first powered up , but if it amplifies the noise floor of the source device set for the system gain structure. that the amplifier front panel gain controls are set levels is to minimum when the system under...
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... clipping On the other hand, the maximum level at the amplifier can receive a supply of both channels will glow. Continued high-temperature operation may be too high and, thus, distorted before it has cooled off the power and check for problems with the wiring, input level, or ...ventilation of the device feeding the amplifier until it reaches the amplifier gain control, either case, no amount of level control adjustment at the...
... clipping On the other hand, the maximum level at the amplifier can receive a supply of both channels will glow. Continued high-temperature operation may be too high and, thus, distorted before it has cooled off the power and check for problems with the wiring, input level, or ...ventilation of the device feeding the amplifier until it reaches the amplifier gain control, either case, no amount of level control adjustment at the...
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... Bad cables Problem with a new, high-quality cable. Connect to see if the problem remains. Symptom No audio from outputs Low output power Bass disappears, speakers sound out of unbalanced Replace the cable with the source Noise induced from a bad AC ground or noisy AC circuit...and proper operation is confirmed, no special considerations are no user adjustments or routine maintenance operations necessary (or available). Time for Alesis Reference Series amplifiers. If you experience problems while operating your RA150/300/500, please use balanced inputs or plug amp and source into the ...
... Bad cables Problem with a new, high-quality cable. Connect to see if the problem remains. Symptom No audio from outputs Low output power Bass disappears, speakers sound out of unbalanced Replace the cable with the source Noise induced from a bad AC ground or noisy AC circuit...and proper operation is confirmed, no special considerations are no user adjustments or routine maintenance operations necessary (or available). Time for Alesis Reference Series amplifiers. If you experience problems while operating your RA150/300/500, please use balanced inputs or plug amp and source into the ...
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... output stage for high reliability under adverse physical and electrical conditions. Output connectors shall be an Alesis RA150/300/500 Reference Series power amplifier. 33 The amplifier shall be two-way binding posts capable of electromagnetic interference. All components shall be differentially balanced ...stacked steel EI laminated transformers for continuous 4 ohm operation with no fan mounted inside the amplifier. The power supplies of 150 watts (RA150), 300 watts (RA300), or 500 watts (RA500) into a 4-ohm load, with no more than .02% total harmonic distortion. Additional ...
... output stage for high reliability under adverse physical and electrical conditions. Output connectors shall be an Alesis RA150/300/500 Reference Series power amplifier. 33 The amplifier shall be two-way binding posts capable of electromagnetic interference. All components shall be differentially balanced ...stacked steel EI laminated transformers for continuous 4 ohm operation with no fan mounted inside the amplifier. The power supplies of 150 watts (RA150), 300 watts (RA300), or 500 watts (RA500) into a 4-ohm load, with no more than .02% total harmonic distortion. Additional ...