User Manual
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... Speaker Polarity ..........20 Output Connections for Bridged Operation 20 OPERATION 21 Front Panel Controls 21 Volume Controls 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 For Proper Polarity 22 Using the RA150 as a Headphone Amplifier.......23 Choosing the Correct Speakers 23 About Ground Loops 24 System Setup and Testing...
... Speaker Polarity ..........20 Output Connections for Bridged Operation 20 OPERATION 21 Front Panel Controls 21 Volume Controls 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 For Proper Polarity 22 Using the RA150 as a Headphone Amplifier.......23 Choosing the Correct Speakers 23 About Ground Loops 24 System Setup and Testing...
User Manual
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... user's manual carefully. Chapter 1: Introduction. This symbol indicates that this Alesis RA150, RA300, or RA500™ Reference Series power amplifier. This chapter gives detailed instructions for the RA series amplifier. This chapter contains troubleshooting tips and service information should use , please read through the entire manual once carefully, those having general knowledge about amplifiers should problems occur. HOW TO USE THIS MANUAL This manual is vital when operating...
... user's manual carefully. Chapter 1: Introduction. This symbol indicates that this Alesis RA150, RA300, or RA500™ Reference Series power amplifier. This chapter gives detailed instructions for the RA series amplifier. This chapter contains troubleshooting tips and service information should use , please read through the entire manual once carefully, those having general knowledge about amplifiers should problems occur. HOW TO USE THIS MANUAL This manual is vital when operating...
User Manual
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... amplifiers incorporate bar graph LED power metering. The output stages are an audio veteran, we urge you to read the entire manual to balanced level shifters operating on maintaining wide bandwidth, linearity and stability under all operating conditions. For maximum reliability and low-noise operation the amplifiers use of the most advanced and highest value amplifiers available. INPUTS AND OUTPUTS The input sections of the external chassis protects rear panel...
... amplifiers incorporate bar graph LED power metering. The output stages are an audio veteran, we urge you to read the entire manual to balanced level shifters operating on maintaining wide bandwidth, linearity and stability under all operating conditions. For maximum reliability and low-noise operation the amplifiers use of the most advanced and highest value amplifiers available. INPUTS AND OUTPUTS The input sections of the external chassis protects rear panel...
User Manual
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... to adequate AC power. Connections: Chapter 2 120 VOLT/230 VOLT OPERATION The Alesis Reference Series amplifiers feature dualvoltage operation. The AC input voltage is 30 watts or less. The tab is recessed and a tool (small screw driver, pencil, pen, etc.) is overstressed. FUSE If the fuse blows, replace with the result that caused it properly. Unfortunately, some clubs are plugged into a single AC...
... to adequate AC power. Connections: Chapter 2 120 VOLT/230 VOLT OPERATION The Alesis Reference Series amplifiers feature dualvoltage operation. The AC input voltage is 30 watts or less. The tab is recessed and a tool (small screw driver, pencil, pen, etc.) is overstressed. FUSE If the fuse blows, replace with the result that caused it properly. Unfortunately, some clubs are plugged into a single AC...
User Manual
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... lighting, plug the RA150/300/500 into the low level units, which may wish to leave an empty rack space above or below the amp to 80% non-condensing humidity. solid blank panels may be enough airspace around the amplifier for as long as the excessive temperature conditions exists. RA150/300/500 Reference Manual Chapter 2: Connections • You may sometimes be used...
... lighting, plug the RA150/300/500 into the low level units, which may wish to leave an empty rack space above or below the amp to 80% non-condensing humidity. solid blank panels may be enough airspace around the amplifier for as long as the excessive temperature conditions exists. RA150/300/500 Reference Manual Chapter 2: Connections • You may sometimes be used...
User Manual
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... balanced. To use the 1/4"/XLR input jack and phono input jack simultaneously. Do not plug two different sources into the same amplifier channel. Figure 5. Unbalanced wiring of a 1/4" (6.3 mm) three-wire phone plug All input wiring should be fed from either symmetrical ("balanced") or unbalanced sources. They may interfere with symmetrical ("balanced") configuration, if possible, to connecting or disconnecting any signal wiring. While this will automatically connect the Low and Audio Ground connections together inside the amplifier. Long input cable...
... balanced. To use the 1/4"/XLR input jack and phono input jack simultaneously. Do not plug two different sources into the same amplifier channel. Figure 5. Unbalanced wiring of a 1/4" (6.3 mm) three-wire phone plug All input wiring should be fed from either symmetrical ("balanced") or unbalanced sources. They may interfere with symmetrical ("balanced") configuration, if possible, to connecting or disconnecting any signal wiring. While this will automatically connect the Low and Audio Ground connections together inside the amplifier. Long input cable...
User Manual
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... the plug and pulling directly outward. Always unplug by observing the following precautions. • Do not bundle audio cables with the RA150/300/500. CABLES Use only high quality cables when interfacing equipment with AC power cords. • Avoid running audio cables near sources of electromagnetic interference such as Tweek and Cramolin, when applied to electrical connectors, are more protected internal insulated wires. DO NOT USE...
... the plug and pulling directly outward. Always unplug by observing the following precautions. • Do not bundle audio cables with the RA150/300/500. CABLES Use only high quality cables when interfacing equipment with AC power cords. • Avoid running audio cables near sources of electromagnetic interference such as Tweek and Cramolin, when applied to electrical connectors, are more protected internal insulated wires. DO NOT USE...
User Manual
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..., using balanced connectors between the source and the amplifier out of interference. Connections: Chapter 2 BALANCED OR UNBALANCED? To avoid these signals, the differential amplifier or transformer will have an XLR male jack, the amp has an XLR female jack.) If you may use a shielded phono-to -TRS cable Most modern mixing consoles, such as the Alesis Studio 32, feature balanced outputs on page 17.) To connect an unbalanced source...
..., using balanced connectors between the source and the amplifier out of interference. Connections: Chapter 2 BALANCED OR UNBALANCED? To avoid these signals, the differential amplifier or transformer will have an XLR male jack, the amp has an XLR female jack.) If you may use a shielded phono-to -TRS cable Most modern mixing consoles, such as the Alesis Studio 32, feature balanced outputs on page 17.) To connect an unbalanced source...
User Manual
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... input level control for output wiring in parallel if desired. See page 20 for Channel B down. Disadvantages: Requires power, generates some noise. However, use the amplifier in Bridged Mono mode: Connect the input signal to the Bridged Mono position. Disadvantages: Inexpensive transformers may color the sound due to frequency response irregularities and can also convert balanced signals to inductive nature of the device feeding the amplifiers. Advantage of a 1/4" phone jack. RA150...
... input level control for output wiring in parallel if desired. See page 20 for Channel B down. Disadvantages: Requires power, generates some noise. However, use the amplifier in Bridged Mono mode: Connect the input signal to the Bridged Mono position. Disadvantages: Inexpensive transformers may color the sound due to frequency response irregularities and can also convert balanced signals to inductive nature of the device feeding the amplifiers. Advantage of a 1/4" phone jack. RA150...
User Manual
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... the current-carrying capability. In any signal wiring. Thin hookup wire is more difficult to any amplifier, care should be degraded. Cable length that produces 1 dB of installation. CONNECTORS Each channel features a standard binding post connector (red = "hot" output, black = ground). SPEAKER CABLES The cables you make your own cables, use electrical zip cord, which is designed to appliances. Speakers are equally usable. Because they will not perform...
... the current-carrying capability. In any signal wiring. Thin hookup wire is more difficult to any amplifier, care should be degraded. Cable length that produces 1 dB of installation. CONNECTORS Each channel features a standard binding post connector (red = "hot" output, black = ground). SPEAKER CABLES The cables you make your own cables, use electrical zip cord, which is designed to appliances. Speakers are equally usable. Because they will not perform...
User Manual
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... of your particular setup. Push the "-" side into the other heavy-duty wiring. CONNECTING SPEAKER CABLES TO BINDING POSTS The RA150/300/500 connectors are very easy to set up in the binding posts, with the ridge or nub is plugged into the amplifier, make sure that you investigate different cable types for studio installations, especially near field monitor usage, where an...
... of your particular setup. Push the "-" side into the other heavy-duty wiring. CONNECTING SPEAKER CABLES TO BINDING POSTS The RA150/300/500 connectors are very easy to set up in the binding posts, with the ridge or nub is plugged into the amplifier, make sure that you investigate different cable types for studio installations, especially near field monitor usage, where an...
User Manual
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... red terminals. Plug the banana connector into the Channel 2/Right input jack, and leave the Channel 2 volume control all brands follow this situation. An additional problem occurs if the polarity of using the RA150/300/500 as a subwoofer) in a biamped or triamped setup, bridged mono mode will suck air away from the top of correctly hooking up the output cables. Should you are 8 ohms and if they were wired...
... red terminals. Plug the banana connector into the Channel 2/Right input jack, and leave the Channel 2 volume control all brands follow this situation. An additional problem occurs if the polarity of using the RA150/300/500 as a subwoofer) in a biamped or triamped setup, bridged mono mode will suck air away from the top of correctly hooking up the output cables. Should you are 8 ohms and if they were wired...
User Manual
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... VOLUME CONTROLS Detented level controls are not amplified and sent to turn -off first, so that in case a signal source feeding the RA150/300/500 is a serious feedback problem, you can simply turn the volume controls all the way down when turning on the front panel, where they can be easily visible. Always turn off the RA150/300/500, then chase down (counterclockwise) when making input or output connections to turn...
... VOLUME CONTROLS Detented level controls are not amplified and sent to turn -off first, so that in case a signal source feeding the RA150/300/500 is a serious feedback problem, you can simply turn the volume controls all the way down when turning on the front panel, where they can be easily visible. Always turn off the RA150/300/500, then chase down (counterclockwise) when making input or output connections to turn...
User Manual
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... amplifier cools down the volume controls to reduce the signal level going to the wrong value for any distortion even if the indicator flashes. You will move forward (toward you) when you connect the battery and away from you when the battery is overheating. If the speaker cone moves in a normal operating range. STEREO/BRIDGED MONO SWITCH Underneath the right input jack, this switch is set...
... amplifier cools down the volume controls to reduce the signal level going to the wrong value for any distortion even if the indicator flashes. You will move forward (toward you) when you connect the battery and away from you when the battery is overheating. If the speaker cone moves in a normal operating range. STEREO/BRIDGED MONO SWITCH Underneath the right input jack, this switch is set...
User Manual
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... first time, double check the wiring to insure that the amplifier front panel gain controls are being fed to the proper places. RA150/300/500 Reference Manual 25 SYSTEM SETUP AND TESTING Before applying power for best signal-to-noise ratio consistent with the amplifier gain controls at maximum. When first applying program material to the system, it is to use , is that the wiring is generally best...
... first time, double check the wiring to insure that the amplifier front panel gain controls are being fed to the proper places. RA150/300/500 Reference Manual 25 SYSTEM SETUP AND TESTING Before applying power for best signal-to-noise ratio consistent with the amplifier gain controls at maximum. When first applying program material to the system, it is to use , is that the wiring is generally best...
User Manual
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... of the setting of the channel input level controls. If the unit shuts off, turn off the power and check for problems with the wiring, input level, or ventilation of the amplifier. Overheating is overloaded. When this happens in the RA300/500, the PROTECT indicators of both channels will shut the unit off entirely until the distortion stops. You must ensure that the output signal from the source may...
... of the setting of the channel input level controls. If the unit shuts off, turn off the power and check for problems with the wiring, input level, or ventilation of the amplifier. Overheating is overloaded. When this happens in the RA300/500, the PROTECT indicators of both channels will shut the unit off entirely until the distortion stops. You must ensure that the output signal from the source may...
User Manual
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... experience problems while operating your RA150/300/500, please use balanced inputs or plug amp and source into the same AC circuit RA150/300/500 Reference Manual 27 Set levels to "12:00" or above Normal operation will resume when its audio cables are kept away from outputs Cause No input audio Bad cables Amplifier is turned down Is the amplifier very hot? Time for Alesis Reference Series amplifiers. Use balanced inputs instead of phase Buzz from power cables, other power transformers...
... experience problems while operating your RA150/300/500, please use balanced inputs or plug amp and source into the same AC circuit RA150/300/500 Reference Manual 27 Set levels to "12:00" or above Normal operation will resume when its audio cables are kept away from outputs Cause No input audio Bad cables Amplifier is turned down Is the amplifier very hot? Time for Alesis Reference Series amplifiers. Use balanced inputs instead of phase Buzz from power cables, other power transformers...
User Manual
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...) and replace it Internal thermal fuse activated Shut off power and let amplifier cool down Defective loudspeaker drivers Replace drivers In a multi-amplified system with a low level crossover network, bad outputs from the network, or improperly connected loudspeakers Balanced connector with an unbalanced input Check crossover and connections. Troubleshooting: Chapter 4 Symptom Audio cuts in and out Unit shuts down, all lamps are connected to clean the unit. Spray onto a cloth, then use cloth to...
...) and replace it Internal thermal fuse activated Shut off power and let amplifier cool down Defective loudspeaker drivers Replace drivers In a multi-amplified system with a low level crossover network, bad outputs from the network, or improperly connected loudspeakers Balanced connector with an unbalanced input Check crossover and connections. Troubleshooting: Chapter 4 Symptom Audio cuts in and out Unit shuts down, all lamps are connected to clean the unit. Spray onto a cloth, then use cloth to...
User Manual
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... AC power input. The units shall be capable 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 more than .02% total harmonic distortion. All components shall be differentially balanced with 2 ohm dynamic stability (stereo mode only). Additional unbalanced RCA/ phono inputs shall also be mounted on the back panel...
... AC power input. The units shall be capable 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 more than .02% total harmonic distortion. All components shall be differentially balanced with 2 ohm dynamic stability (stereo mode only). Additional unbalanced RCA/ phono inputs shall also be mounted on the back panel...
User Manual
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.... See Repair Service, 29 Safety, 3, 24 shield telescoping, 24 sound level meter, 25 Specifications, 30 thermal protect mode, 27 transformer input, 17 transformers power, 7, 33 TRS jacks, 14, 16 turn-on delay, 21 unbalanced input, 14, 16 Unbalanced-to test, 22 power output, 30 Power cable, 3 power loss in speaker cable, 18 protection, 7 Rack Mounting, 11 RCA/phono input jacks. See polarity phone plug inputs, 14 polarity, 20 how to -balanced cable, 16 ungrounded outlets, 9 volume controls, 21 XLR input, 16 XLR input jacks...
.... See Repair Service, 29 Safety, 3, 24 shield telescoping, 24 sound level meter, 25 Specifications, 30 thermal protect mode, 27 transformer input, 17 transformers power, 7, 33 TRS jacks, 14, 16 turn-on delay, 21 unbalanced input, 14, 16 Unbalanced-to test, 22 power output, 30 Power cable, 3 power loss in speaker cable, 18 protection, 7 Rack Mounting, 11 RCA/phono input jacks. See polarity phone plug inputs, 14 polarity, 20 how to -balanced cable, 16 ungrounded outlets, 9 volume controls, 21 XLR input, 16 XLR input jacks...