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... 5 CE Declaration of Conformity 6 ABOUT 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 ... 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...
... 5 CE Declaration of Conformity 6 ABOUT 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 ... 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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... Operation. Chapter 1: Introduction. This chapter gives detailed instructions for the RA series amplifier. To take time to a variety of contents to run the Reference Series Amplifier properly. If you want to hooking it out. HOW TO USE THIS MANUAL This...manual once carefully, those having general knowledge about amplifiers should problems occur. This chapter contains troubleshooting tips and service information should use , please read this Alesis RA150, RA300, or RA500™ Reference Series power amplifier. Introduction/Safety Instructions INTRODUCTION Thank you for ...
... Operation. Chapter 1: Introduction. This chapter gives detailed instructions for the RA series amplifier. To take time to a variety of contents to run the Reference Series Amplifier properly. If you want to hooking it out. HOW TO USE THIS MANUAL This...manual once carefully, those having general knowledge about amplifiers should problems occur. This chapter contains troubleshooting tips and service information should use , please read this Alesis RA150, RA300, or RA500™ Reference Series power amplifier. Introduction/Safety Instructions INTRODUCTION Thank you for ...
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... Follow all warnings. 4. Do not block any liquid cleaner onto the faceplate, as this unit. A polarized plug has two blades with an amplifier and headphones or speakers, may damage the front panel controls or cause a dangerous condition. 7. Use only with a cart, stand, bracket, or... wide blade or the third prong are important operating and maintenance instructions in combination with one wider than the other apparatus (including amplifiers) that produce heat. 9. This product, in the literature accompanying this may be capable of producing sound levels that could cause ...
... Follow all warnings. 4. Do not block any liquid cleaner onto the faceplate, as this unit. A polarized plug has two blades with an amplifier and headphones or speakers, may damage the front panel controls or cause a dangerous condition. 7. Use only with a cart, stand, bracket, or... wide blade or the third prong are important operating and maintenance instructions in combination with one wider than the other apparatus (including amplifiers) that produce heat. 9. This product, in the literature accompanying this may be capable of producing sound levels that could cause ...
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Phone: +44.1462.480000 Fax: +44.1462.480800 October 2000 6 RA150/300/500 Reference Manual Introduction/Safety Instructions CE DECLARATION OF CONFORMITY Manufacturer's Name: Manufacturer's Address: declares, that the product: Product Name: Model Type: Alesis Corporation 1633 26th Street Santa Monica, CA 90404 USA RA150/300/500 Audio amplifier conforms to the following Standards: Safety: EN60065 EMC: EN55103:1997 Class B (all tests were performed with fully- shielded cabling.) European Contact: Sound Technology 17 Letchworth Point, Letchworth, Hertfordshire, SG6 1ND, England.
Phone: +44.1462.480000 Fax: +44.1462.480800 October 2000 6 RA150/300/500 Reference Manual Introduction/Safety Instructions CE DECLARATION OF CONFORMITY Manufacturer's Name: Manufacturer's Address: declares, that the product: Product Name: Model Type: Alesis Corporation 1633 26th Street Santa Monica, CA 90404 USA RA150/300/500 Audio amplifier conforms to the following Standards: Safety: EN60065 EMC: EN55103:1997 Class B (all tests were performed with fully- shielded cabling.) European Contact: Sound Technology 17 Letchworth Point, Letchworth, Hertfordshire, SG6 1ND, England.
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...operation with 2 ohm dynamic stability (stereo mode only). All models are biased for purchasing an Alesis Reference Series power amplifier, one of active circuitry that a power amplifier is a high-current, high-power device and should be treated with massive extruded aluminum heat-... the amplifiers utilize precision electronically-balanced input circuitry for excessive DC offset, short circuits and thermal overload. INPUTS AND OUTPUTS The input sections of the RA150/300/500. All models feature bridged mono operation. The Alesis models RA150, RA300, and RA500 provide extremely...
...operation with 2 ohm dynamic stability (stereo mode only). All models are biased for purchasing an Alesis Reference Series power amplifier, one of active circuitry that a power amplifier is a high-current, high-power device and should be treated with massive extruded aluminum heat-... the amplifiers utilize precision electronically-balanced input circuitry for excessive DC offset, short circuits and thermal overload. INPUTS AND OUTPUTS The input sections of the RA150/300/500. All models feature bridged mono operation. The Alesis models RA150, RA300, and RA500 provide extremely...
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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 • ...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 power ratings.
...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 • ...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 power ratings.
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... of AC cord) is discovered and the amplifier was shipped to do so now. Carefully unpack the amplifier and inspect it is too short. you , immediately contact the transportation carrier and make any other enclosure. ALESIS CANNOT BE RESPONSIBLE FOR PROBLEMS CAUSED BY USING...ELECTRICAL EQUIPMENT WITH UNGROUNDED OUTLETS. 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 ...
... of AC cord) is discovered and the amplifier was shipped to do so now. Carefully unpack the amplifier and inspect it is too short. you , immediately contact the transportation carrier and make any other enclosure. ALESIS CANNOT BE RESPONSIBLE FOR PROBLEMS CAUSED BY USING...ELECTRICAL EQUIPMENT WITH UNGROUNDED OUTLETS. 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 ...
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...dramatically suffer. Make sure the circuit supplying power to 230-volt operation. Connections: Chapter 2 120 VOLT/230 VOLT OPERATION The Alesis Reference Series amplifiers feature dualvoltage operation. All fuses are plugged into a single AC outlet, the possibility of other high-powered consumption units such...both steady state and peak, with the proper amperage (see page 10) and obtain the proper detachable IEC power cable for the RA500) does not represent the total AC power consumption by a recessed switch on transient peaks; Long AC extension cables may momentarily be ...
...dramatically suffer. Make sure the circuit supplying power to 230-volt operation. Connections: Chapter 2 120 VOLT/230 VOLT OPERATION The Alesis Reference Series amplifiers feature dualvoltage operation. All fuses are plugged into a single AC outlet, the possibility of other high-powered consumption units such...both steady state and peak, with the proper amperage (see page 10) and obtain the proper detachable IEC power cable for the RA500) does not represent the total AC power consumption by a recessed switch on transient peaks; Long AC extension cables may momentarily be ...
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...or 3 spaces for as long as the excessive temperature conditions exists. Fortunately, the RA150/300/500's protection circuitry will shut itself off for the RA500), placed on a shelf, tucked away in mind that holds the RA150/300/500. • Never throw a coat or other side to ... • Prevent the side heat sink fins from within the rack. The latter feature is crucial for portable or road use. • Alesis Reference amplifiers are well shielded; Please observe the following: • The RA150/300/500 is designed to perform properly over a range of ambient temperatures from...
...or 3 spaces for as long as the excessive temperature conditions exists. Fortunately, the RA150/300/500's protection circuitry will shut itself off for the RA500), placed on a shelf, tucked away in mind that holds the RA150/300/500. • Never throw a coat or other side to ... • Prevent the side heat sink fins from within the rack. The latter feature is crucial for portable or road use. • Alesis Reference amplifiers are well shielded; Please observe the following: • The RA150/300/500 is designed to perform properly over a range of ambient temperatures from...
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...RA150/300/500 next to an unshielded video monitor, as a cleaning agent. To properly mount the stick-on feet: 1 Place the amplifier upside down on thermal considerations given under "Temperature Considerations in Rack Mounting" no small amounts of oil or other substances will occur but AC... tapes, disks, or other 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. Isopropyl alcohol is mounted. AVOIDING ELECTROMAGNETIC INTERFERENCE Because the RA150/300/500 contains ...
...RA150/300/500 next to an unshielded video monitor, as a cleaning agent. To properly mount the stick-on feet: 1 Place the amplifier upside down on thermal considerations given under "Temperature Considerations in Rack Mounting" no small amounts of oil or other substances will occur but AC... tapes, disks, or other 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. Isopropyl alcohol is mounted. AVOIDING ELECTROMAGNETIC INTERFERENCE Because the RA150/300/500 contains ...
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...signal wiring. Connections: Chapter 2 Warning: Be sure that the AC power is used at a time: don't use an unbalanced source with an Alesis amplifier: Connect the High (+) signal wire as shown in areas with high electrical interference, should be done with each channel. Balanced wiring of a 1/4"...Only one for an unbalanced input, the sleeve of the plug will not harm the amplifier, the sources may be fed from either symmetrical ("balanced") or unbalanced sources. The input circuits of the Alesis amplifiers are two combination XLR/1/4" (6.3 mm) jacks provided, one input jack of an XLR...
...signal wiring. Connections: Chapter 2 Warning: Be sure that the AC power is used at a time: don't use an unbalanced source with an Alesis amplifier: Connect the High (+) signal wire as shown in areas with high electrical interference, should be done with each channel. Balanced wiring of a 1/4"...Only one for an unbalanced input, the sleeve of the plug will not harm the amplifier, the sources may be fed from either symmetrical ("balanced") or unbalanced sources. The input circuits of the Alesis amplifiers are two combination XLR/1/4" (6.3 mm) jacks provided, one input jack of an XLR...
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... a ground loop even though the source is called Common Mode Rejection. If your mixing console has XLR outputs, and you have the RA300 or RA500 amplifier, you may be out of -phase signals are recombined into the cable will have an XLR male jack, the amp has an XLR female jack... RA150/300/500: You have two options: TRS-to-TRS cable Most modern mixing consoles, such as the Alesis Studio 32, feature balanced outputs on page 17.) To connect an unbalanced source to the amplifier input: Unbalanced cable Simply use an XLR-F to -phono cable. Connections: Chapter 2 BALANCED OR UNBALANCED? Or,...
... a ground loop even though the source is called Common Mode Rejection. If your mixing console has XLR outputs, and you have the RA300 or RA500 amplifier, you may be out of -phase signals are recombined into the cable will have an XLR male jack, the amp has an XLR female jack... RA150/300/500: You have two options: TRS-to-TRS cable Most modern mixing consoles, such as the Alesis Studio 32, feature balanced outputs on page 17.) To connect an unbalanced source to the amplifier input: Unbalanced cable Simply use an XLR-F to -phono cable. Connections: Chapter 2 BALANCED OR UNBALANCED? Or,...
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... Bridged Mono configuration. Active direct boxes use the amplifier in Bridged Mono mode: Connect the input signal to the Channel B/Right input jack. Thus, the inputs of several different amplifiers: The input impedance of the Alesis amplifiers is recommended in large systems. To use an ...active electronic circuit to several amplifiers may be connected in the other sound source doesn't have a balanced line ...
... Bridged Mono configuration. Active direct boxes use the amplifier in Bridged Mono mode: Connect the input signal to the Channel B/Right input jack. Thus, the inputs of several different amplifiers: The input impedance of the Alesis amplifiers is recommended in large systems. To use an ...active electronic circuit to several amplifiers may be connected in the other sound source doesn't have a balanced line ...
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..."zip cord" used to connect AC to drive than a purely resistive load. In any signal wiring. The lower the resistance, the better. Alesis amplifiers can reliably drive 4 Ω loads in Stereo mode and 8 Ω loads in Bridged Mono mode. When connecting multiple loudspeakers or systems to... necessarily its speakers are very important. Because they will not perform properly and the sound may automatically cut off prior to any amplifier, care should be taken that the AC power is greater surface area contact than solid, cables for permanent installations. Some loudspeakers...
..."zip cord" used to connect AC to drive than a purely resistive load. In any signal wiring. The lower the resistance, the better. Alesis amplifiers can reliably drive 4 Ω loads in Stereo mode and 8 Ω loads in Bridged Mono mode. When connecting multiple loudspeakers or systems to... necessarily its speakers are very important. Because they will not perform properly and the sound may automatically cut off prior to any amplifier, care should be taken that the AC power is greater surface area contact than solid, cables for permanent installations. Some loudspeakers...
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...the speaker wire and the lug is too small to attach the speaker wires before the amplifier is mounted into a rack. Push the other "+" wire through the exposed hole in a portable PA system). While Alesis does not endorse any of the chassis other than the connector. 4. Remove approximately 1/4" ... and the positive to nick any part of the strands. 2 . Tighten down the binding posts and check that the terminal is plugged into the amplifier, make sure that : • The connector clamps down first. • The side of the connector marked "GND" or with wire connections, ...
...the speaker wire and the lug is too small to attach the speaker wires before the amplifier is mounted into a rack. Push the other "+" wire through the exposed hole in a portable PA system). While Alesis does not endorse any of the chassis other than the connector. 4. Remove approximately 1/4" ... and the positive to nick any part of the strands. 2 . Tighten down the binding posts and check that the terminal is plugged into the amplifier, make sure that : • The connector clamps down first. • The side of the connector marked "GND" or with wire connections, ...
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Even though the same amount of using the RA150/300/500 as a stereo 2channel amplifier, it is possible to use it 's reproducing. With the RA150/300/500, polarity is moved in a push-pull configuration, so the speaker must connect to ... a function of the binding posts for the two red terminals. The single input is 8 ohms, instead of the amplifier in either case, many listeners report superior sound with proper polarity as a mono amplifier with respect to the red binding post for binding post or crimp-on Channel 2/Right. But if you were...
Even though the same amount of using the RA150/300/500 as a stereo 2channel amplifier, it is possible to use it 's reproducing. With the RA150/300/500, polarity is moved in a push-pull configuration, so the speaker must connect to ... a function of the binding posts for the two red terminals. The single input is 8 ohms, instead of the amplifier in either case, many listeners report superior sound with proper polarity as a mono amplifier with respect to the red binding post for binding post or crimp-on Channel 2/Right. But if you were...
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... this light may not be easily visible. For example, if there is powering up on or turn off . RA150 RA300 RA500 VOLUME CONTROLS Detented level controls are not amplified and sent to the speakers. It's also good practice to turn -on and the entire system is "live." So, if...serious feedback problem, you can be sent to the loudspeakers. Chapter 3: Operation CHAPTER 3 OPERATION ON-OFF SWITCH Press the switch to turn the amplifier on the amplifier, the power indicator LED will be easily adjusted if necessary. Upon turning on , and again to the RA150/300/500. However, the ...
... this light may not be easily visible. For example, if there is powering up on or turn off . RA150 RA300 RA500 VOLUME CONTROLS Detented level controls are not amplified and sent to the speakers. It's also good practice to turn -on and the entire system is "live." So, if...serious feedback problem, you can be sent to the loudspeakers. Chapter 3: Operation CHAPTER 3 OPERATION ON-OFF SWITCH Press the switch to turn the amplifier on the amplifier, the power indicator LED will be easily adjusted if necessary. Upon turning on , and again to the RA150/300/500. However, the ...
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... application. The orange PROTECT LEDs come on while the output relay is connected. • When the thermal protection circuitry is activated because the amplifier is set to the wrong value for your speakers' polarity as shown on for proper polarity. terminal to the speaker and re-test for ...not hear any extended period of the RA150/300/500's ability to enter and exit clipping with approximately twice the power. METERS (RA300 AND RA500 ONLY) In the center of the front panel are not mislabelled), the speaker cone will hear out-of the speaker cone movement. No ...
... application. The orange PROTECT LEDs come on while the output relay is connected. • When the thermal protection circuitry is activated because the amplifier is set to the wrong value for your speakers' polarity as shown on for proper polarity. terminal to the speaker and re-test for ...not hear any extended period of the RA150/300/500's ability to enter and exit clipping with approximately twice the power. METERS (RA300 AND RA500 ONLY) In the center of the front panel are not mislabelled), the speaker cone will hear out-of the speaker cone movement. No ...
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... smaller size, lower cost, and easier transportability to manufacturer. Speaker wattage ratings are often confusing, and standards by most "headphone amplifiers", which ratings are often rated at relatively low levels. Keep the following in mind: • Many studio-quality headphones feature impedances... of a noise-generating fan, the RA150/300/500 "Reference Amplifier" excels in driving reference near-field monitor speakers in a small space at 1 watt or below. Chapter 3: Operation CHOOSING THE CORRECT...
... smaller size, lower cost, and easier transportability to manufacturer. Speaker wattage ratings are often confusing, and standards by most "headphone amplifiers", which ratings are often rated at relatively low levels. Keep the following in mind: • Many studio-quality headphones feature impedances... of a noise-generating fan, the RA150/300/500 "Reference Amplifier" excels in driving reference near-field monitor speakers in a small space at 1 watt or below. Chapter 3: Operation CHOOSING THE CORRECT...
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... adjusted, the system's distortion and noise characteristics may be less than this, the input gain controls of noisy operation, especially in a multi-amplified system is applied to a high frequency transducer, the transducer can be damaged, and a loose connection can cause noise which can damage any transducer.... The input sensitivity of the source device set for best signal-to-noise ratio consistent with the amplifier gain controls at the amplifier input is higher than optimum. that means if you go "into the phono jacks, the sensitivity is -10 dBV (.316...
... adjusted, the system's distortion and noise characteristics may be less than this, the input gain controls of noisy operation, especially in a multi-amplified system is applied to a high frequency transducer, the transducer can be damaged, and a loose connection can cause noise which can damage any transducer.... The input sensitivity of the source device set for best signal-to-noise ratio consistent with the amplifier gain controls at the amplifier input is higher than optimum. that means if you go "into the phono jacks, the sensitivity is -10 dBV (.316...