Parasound 2250 Stereo Amplifier User Manual
Contents
1. 9 Typical Problems and Remedies 10 Are You Having Difficulty 11 Warranty Repairs 065 vin apr idea vale 11 Specifications 131 45 OR inte ai a Pale A are ia 12 Connection and Setup Notes 13 INTRODUCTION Congratulations and thank you for your purchase of this precision Parasound audio component The Parasound Model 2250 is the latest generation of popular and proven audio power amplifi ers dating back to 1981 It has been designed for a wide variety of applications establishing a new standard for audio performance user friendliness and utility in custom installations The versatility of the Model 2250 allows many connection and configuration options so please be sure to read this manual thoroughly before you begin installation Unpacking Carefully unpack your Model 2250 and these accessories e Detachable AC power cord e Black trigger wire with a 2 5 mm sub mini plug at both ends e Black trigger wire with a 2 5 mm plug at one end 3 5mm mini plug at the other end Please inspect the unit now and contact your Parasound Dealer promptly if you see evidence of shipping damage Save the carton and packing inserts in case you move or in the event you need to ship your amplifier for repair Before you proceed locate the serial number on the rear panel or underside of the unit and record it here for futu2. Note The Model 2250 creates more heat when it drives a bridged mono speaker or multiple speaker pairs Lower impedance speakers will make it run even hotter Heat greatly reduces the life of the amplifier and nearby components Please heed the instructions for setting the Load Impedance switch to avoid overheating Load Impedance Switch Load Impedance 2 3 4 8 Ohms Ohms REAR PANEL CONNECTIONS AND CONTROLS continued O For a single pair of 4 ohm or 8 ohm speakers the Load Impedance switch may be set to its 4 8 Ohms position The Load Impedance Switch must be set to 2 3 ohms whenever the load will be lower than 4 ohms Speaker loads below 4 ohms impedance can cause the Model 2250 to over heat rapidly and cause audible distortion These are examples that require the 2 3 ohms setting 1 Driving two pairs of speakers whose impedances you don t know 2 Driving two pairs of speakers with impedances that are lower than 8 ohms Two pairs of 4 ohm speakers driven simultaneously are a 2 ohm load 3 Driving a single 4 ohm speaker bridged to mono This is a 2 ohm load 4 Driving two 8 ohm speakers bridged to mono This is a 2 ohm load Note For the coolest possible operating temperature we recommend setting the Load Impedance switch to 2 3 ohms even if you are using a single pair of 8 ohm speakers Automatic Turn On and Off Auto Turn On Switch For convenience there are two ways the Model 2250 can be triggered to turn on automa
3. ground wires of the various AC cords Ground Lift Norm AC Power Connections and AC Grounding If possible plug your Model 2250 into the same AC outlet that your accompanying audio com ponents especially then preamp or system controller are plugged into The ground potential between different AC outlets may be higher or lower resulting in audible hum FRONT PANEL BUTTONS AND DISPLAY Power Button Press the Power button once to turn the Model 2250 on press it again to turn it off The Power button is inoperative when the Auto Turn On switch is set to Audio or 12V Note It is normal for the 2250 Protect indicator to flash briefly right after turn on A Y B Protect E R Hi Temp A and B Speaker Select Buttons These buttons turn on the speaker pairs connected to the corresponding Speaker Pair A and B terminals They will also select two single mono speakers Note The front panel buttons and switches activate relays which perform the actual speaker switching The contacts in the relays will last longer if you don t press the A and B buttons to turn speaker pairs on and off while the 2250 is playing at high volume L and R Channel Indicators L and R will illuminate green when the Model 2250 is turned on and is operating normally The green L or R indicator will not light if the fault condition is only in that channel Neither L or R will illuminate if there is a general fault or if the temperature is to
4. not overload wall outlets or extension cords This can result in a fire or electric shock 4 Inserting Objects into Unit Never push objects of any kind into this product through any openings they may touch dangerous voltage points or short out parts that could result in fire or electric shock 5 Servicing Do not attempt to repair or service this product yourself Opening or removing covers may expose you to dangerous voltage and other hazards Refer all servicing to qualified service personnel 6 Damage Requiring Service Unplug this product from the wall outlet and refer servicing to quali fied service personnel under the following conditions a If the power supply cord or plug is damaged b If liquid has been spilled into the product c If the product has been exposed to rain or water d If the product does not operate normally by following the operating instructions e If the product has been dropped or damaged in any way f If the product exhibits a distinct change in performance 17 Replacement Parts When replacement parts are required be sure the service technician has used replacement parts specified by the manufacturer Unauthorized substitutions may result in fire elec tric shock and other hazards 19 Safety Check Upon completion of any service or repairs to this product ask the service technician to perform safety checks to determine that the product is in proper operating condition 20 Wall or Cei
5. of films the surround channel levels are even lower than the minimum level required by the Audio sensing circuit 12V In Jack The Model 2250 12V input uses a 2 5mm sub mini jack To trigger the Model 2250 insert the plug at one end of the provided trigger wire into this jack and the other plug at the other end into the source component s trigger output jack Some components including most Parasound Surround Controllers may use a 3 5mm mini jack for trigger output so we have also included a included a 2 5mm jack 3 5mm plug adapter for your convenience REAR PANEL CONNECTIONS AND CONTROLS continued Manual Audio Sens 12V Trigger O In Loop 4 las Audio 12V Max Min O O Auto Turn On Note f the controller s trigger output is a and terminal you can cut the 2 5mm plug off one end of the included trigger wire and attach the bare wires to these terminals The lead with the white stripe on it corresponds to the plug s tip and the unmarked lead corresponds to the sleeve of the plug Note l the trigger voltage source is DC the trigger plug tip must be positive and its sleeve negative 12V Out Jack The Trigger Out jack lets you loop or daisy chain the incoming trigger voltage to an additional Model 2250 or other component Note The Model 2250 trigger circuit draws a negligible 15 mA from the controller The total load on your controller s trigger output s is the sum of the trigger cur
6. D PARASOUND NEWCLASSIC PARASOUND Hi Temp Model 2250 Two Channel Power Amplifier OWNER S GUIDE IMPORTANT SAFETY INSTRUCTIONS The lightning flash with the arrowhead symbol within an equilateral triangle is intended to alert the user to the presence of dangerous voltage inside the product that may constitute a risk of electric shock The exclamation point within an equilateral triangle is intended to alert the user to the presence of important operating and maintenance instructions in the literature accompanying the product TO REDUCE THE RISK OF ELECTRIC SHOCK DO NOT REMOVE COVER NO USER SERVICEABLE PARTS INSIDE REFER SERVICING TO QUALIFIED SERVICE PERSONNEL 1 Read Instructions Read all the safety and operating instructions before operating this product 2 Retain Instructions Retain safety and operating instructions for future reference 3 Heed Warnings Adhere to all warnings on the product and in the operating instructions 4 Follow Instructions Follow all operating and use instructions 5 Cleaning Unplug this product from the wall outlet before cleaning Use a damp cloth for cleaning Clean the outside of the product only 6 Attachments Do not use attachments that are not recommended by the product manufacturer they may be hazardous 7 Water and Moisture Do not use this product near water 8 Accessories Do not place this product on an unstable cart or stand The produ
7. NS AND CONTROLS continued O High Pass Filter Switch The High Pass filter can improve the sound in virtually any installation It s called a high pass filter because it permits signals higher than 20 Hz and 40 Hz to pass while preventing signals below these frequencies from passing High Pass Filter Flat 20Hz 40Hz The Flat switch position disconnects the filter and the 2250 s frequency response is flat The 20 Hz switch position filters out frequencies below 20 Hz Your speakers have greater dynamic range and far less distortion when they don t receive frequencies which are lower than they can reproduce Likewise the 2250 operates more efficiently when it s not called upon to amplify frequencies which the speakers can t reproduce Because the 20 Hz filter has a steep 18 dB per octave slope it is essentially a sub sonic filter and you probably won t notice any loss of bass unless you re using very large speakers The 40 Hz switch position filters bass below 40 Hz at 18 dB per octave This is ideal when the 275 is driving in wall or in ceiling speakers because very few of them can reproduce very much bass below 40 Hz You ll enjoy much cleaner sound and higher undistorted volume levels Not having to amplify bass that s inaudible with your speakers is another way the 275 will run cooler Note Autoformer type passive volume controls are highly reactive loads that are known to cause amplifier malfunction The 20 Hz or 40 Hz fi
8. acks Connect the shielded audio cables from your preamplifier or system controller s output jacks to the Model 2250 s L and R audio Input jacks Use only the R channel jack for mono operation Loop Jacks The jacks replicate the audio input signals to facilitate connections of other power amplifiers to the same preamplifier or system controller Loop connection of multiple power amplifiers is called a daisy chain Note You may loop the trigger connections of multiple Parasound power amplifiers without overloading the surround controller or preamplifier trigger outputs Level Input gt Loop e THX Ref 2no e THX Ref R Right and L Left Level Knobs You can adjust the listening level for each channel by turning its Level knob clockwise to increase gain or counter clockwise to reduce gain The maximum settings correspond to THX Reference Level where the gain is 28 28 1 volt at the input jacks corresponds to a 28 28 volts at the speaker terminals THX recommends this setting whenever the 2250 is installed with other THX certified components Note You may wish to experiment with different gain settings on your preamp or a non THX surround controller and on the Model 2250 to find a combination of gain settings where your system s background noise is lowest Sound professionals call these adjustments gain staging Note Only the R channel Level knob is used for bridged mono operation REAR PANEL CONNECTIO
9. always be turned off before moving this switch For normal operation the Bridging switch must be set to Stereo For bridged mono operation set it to Mono Note Stereo sound will be faint and very distorted if you accidentally leave the Bridging switch in its Mono position Mono Operation We recommend an 8 ohm minimum speaker load for bridged mono operation For mono the Model 2250 5 n bridges the R channel to amplify only the positive half Stereo Mono of the audio signal and the L channel to amplify only the negative half of the audio signal In effect each channel sees only half of the speaker s rated impedance so that an 8 ohm speaker in bridged mono is only a 4 ohm load and a 4 ohm speaker in mono is only a 2 ohm load This is why the mono power output is much higher than the sum of the L and R channel outputs for stereo operation Bridging Mono Input and Speaker Connections Turn the unit off and remove the AC cord Connect the single cable from the preamp or controller to the R channel Input jack Set the Bridging switch to its Mono position Connect the positive lead of the speaker wire to the red R channel speaker pair A terminal Connect the negative lead of the speaker wire to the red L channel speaker pair A terminal Do not connect anything to either the L or R speaker terminals If you have a second mono speaker repeat steps 4 6 with the speaker pair B terminals Reconnect the AC cord dodo OP ON
10. ancisco CA 94111 Customer Service 415 397 7100 Technical Dept 415 675 7272 Fax 415 397 0144 www parasound com rev 0 91 2005 Parasound Products Inc
11. ct may fall causing bodily injury and damage to the product A product and cart combination should be moved with care Quick stops excessive force and uneven surfaces may cause the product and cart to overturn 9 Ventilation Slots and openings in the cabinet are provided for ventilation to ensure reliable opera tion of the product and to protect it from overheating These openings must not be blocked or covered This product should not be placed in a built in installation such as a bookcase or rack unless proper ventilation is provided 10 Power Sources Operate this product only from the type of power source indicated on the label If you are not sure of the type of power supply to your home consult your dealer or local power company This product is equipped with a three prong grounding plug This plug will only fit into a grounding power outlet If you are unable to insert the plug into the outlet contact your electrician to replace your obsolete outlet Do not defeat the safety purpose of the grounding plug 1 Power Cord Protection Power supply cords should be routed so that they are not likely to be walked on or pinched by items placed upon or against them 2 Lightning Unplug the unit from the wall outlet for added protection during a lightning storm and when it is left unattended and unused for long periods of time This will prevent damage to the product due to lightning and power line surges 3 Overloading Do
12. e the unit and try to avoid crowding or stacking the Model 2250 tightly between other components A ventilation fan is also recommended where other equipment must be mounted close to the Model 2250 Do not place the unit on carpeting or any other material that could obstruct air flow into the ventilation holes in its chassis bottom Rack Mounting The Model 2250 front panel occupies only three rack spaces in a standard 19 equipment rack For rack mounting you ll need to use the Parasound RMK33 rack mounting kit purchased separately We recommend that you use the 8 insulated shoulder washers with the four mounting bolts which are included with the RMK33 Position these washers on both sides so they sandwich the front panel before the mounting bolts are screwed into the rack rail This will eliminate metal to metal contact between the Model 2250 chassis the equipment rack and the other components in the rack O REAR PANEL CONNECTIONS AND CONTROLS Connection Precautions Disconnect the AC cord before making or changing any input trigger or speaker wire connections Make sure there is no strain or tension on any wires that could cause them to pull loose E o o MN Re PARASOUND an Francisco CA USA a E A A a A i A E 00090 0000 4 tmon 24 4 4 mono 4 In J
13. ing Auto turn on increase the sensitivity of the audio trigger ls the Hi Temp or Protect or both illuminated Check for excessive temperature short circuited speaker wires low impedance speaker load and inadequate ventilation to remove heat Background Hum Move the Ground switch to Lift Move audio cables and AC cords away from each other Try different routes for the audio cables and AC cords Make sure insulating shoulder washers are used if unit is rack mounted Try reversing the direction of each other component s AC plug one by one Overheating Remove any external sources of heat Increase ventilation around the Model 2250 Reset the Load Impedance switch to 2 3 Ohms IF YOU REQUIRE ASSISTANCE Call your Parasound dealer first If the dealer can t help you with your problem we encourage you to call Parasound s Technical Service Department toll free at 1 866 770 8324 Monday Friday 8am 4pm Pacific time We can suggest other diagnostic tests you can easily perform If we determine that your Model 2250 should be returned to Parasound or an Authorized Parasound Warranty Center for inspection and possible servicing we will provide the location of a warranty center near you or shipping instructions and a Return Authorization number for its return to Parasound Before You Return Any Unit to Parasound for Service Before you send your unit to Parasound you will need to obtain a specific Return Authori
14. ling Mounting Mount the product to a wall or ceiling only as recommended 21 Heat The product should be situated away from heat sources such as radiators heat registers stoves and other products including amplifiers that produce heat www parasound com TABLE OF CONTENTS Unpacking and Accessories 2 115v 230v AC Selector Switch 3 Ventilation Requirements 3 Rack Mounting 22 8 3 2 20000 pia RAR BE ARR Sk Les Oy OE et 3 Rear Panel Connections and Controls 4 Input and Loop Out Jacks 4 Level KnobS ieo crit A es A AAA RE A A 4 High Pass Filter Switch 4 Speaker Connections 2 0 00 00 ee ee 5 Bridging Switch Stereo Mono 5 Mono Input cs cog oe eae ela a ee ee as de Bh WA oo A ee ae 6 Speaker Connections 6 Load Impedance Switch 6 AutoTurmn0Oni he da i ee Bde IG ede te Nw WR a AI et eg 6 Sensitivity Adjust Knob 8 Ground Switeh arean se tate a Boe eh al deg ot eS Pe le E 8 Front Panel Power Button and Speaker Buttons 9 Front Panel Status Indicators
15. lter settings enable the 275 to drive them with ease Speaker Connections There are separate speaker terminals for two pairs of speakers labeled Speaker Pair A and Speaker Pair B Each and speaker terminal will accept bare speaker wire up to AWG 12 a wire terminated with a spade lug or with a single banana plug dual banana plugs which are 19mm apart may be used for each speaker Speaker Pair A Speaker Pair B If you use bare wires remove only enough insulation about 12mm for each exposed bare wire to insert through the small hole in the side of the binding post Before inserting a bare wire twist the strands tightly between your fingers to prevent strays that might touch the chas sis or another terminal and cause a short circuit If you have soldering experience you may want to tin the stripped bare wire with solder for a cleaner termination and to prevent the wire from oxidizing O REAR PANEL CONNECTIONS AND CONTROLS continued Correct Speaker Polarity is Important As you connect the speaker wires you can see that the insulation on one of the two wires in each pair has either printing or a raised ridge The marking lets you know which wire you con nected to the positive speaker terminal at its other end Make sure the wire you attach to each Model 2250 speaker terminal is attached to the terminal of the speaker for that channel Bridging Switch Stereo Mono The Model 2250 power should
16. nit is not eligible for repair under the terms of the Parasound warranty if Unit was not purchased from a Parasound Authorized Dealer or Parasound Authorized Reseller You are not the original owner The warranty is not transferable Unit s serial number was removed modified or defaced Unit shows evidence of abuse and or misuse Unit was modified in any way D0P0N gt A prior repair was attempted by an unauthorized repair station PARASOUND MODEL 2250 SPECIFICATIONS Continuous RMS Power Output 20 Hz 20 kHz Both Channels Driven 250 watts x 2 8 Q 385 watts x 2 4 Q 250 watts x 2 2 Q Continuous RMS Power Output 20 Hz 20 kHz Bridged Mono 600 watts 8 Q 600 watts 4 Q Current Capacity 45 amps peak per channel Frequency Response 20 Hz 50 kHz 0 3 dB 1 watt Dynamic Headroom 1 6 dB Total Harmonic Distortion 0 02 at full rated output 0 015 at average listening levels IM Distortion 0 05 Transient IM Distortion Not measurable S N Ratio 114 dB at rated output IHF A weighted 106 dB at rated output unweighted 93 dB at 2 828 V output IHF A weighted 84 dB at 2 828 V output unweighted Input Impedance 33kQ Input Sensitivity 1 V for 28 28 V out THX standard Inter Channel Crosstalk 85 dB 1 kHz 73 dB 10 kHz 67 dB 20 kHz Damping Factor Over 150 at 20 Hz Auto Turn On DC 9 12V 15 mA Auto Turn On Audio 1 2 mV 12 V adjustable 15 minute turn off delay AC P
17. o high Protect Indicator Protect will illuminate red when the Model 2250 has experienced either an internal or external fault condition which has also activated its protection circuit to prevent internal damage Note lt is normal for Protect to flash for a few seconds right after the unit is turned on Hi Temp Indicator Hi Temp will illuminate red when the Model 2250 reaches its maximum safe operating temperature If the heat persists the unit will soon shut itself off for protection and will remain off until the temperature drops If Hi Temp appears the unit has been over driven at too high a listening level and or too low impedance speaker load or has not been provided with sufficient ventilation Maintaining Your Model 2250 Your Parasound Model 2250 power amplifier requires no periodic maintenance other than the knowledge that you are bragging about it to your friends It has no user serviceable parts inside To avoid the risk of electric shock do not remove its top cover The exterior can be cleaned with a soft cloth pre moistened only with a few drops of water or glass cleaner PROBLEMS AND REMEDIES No sound Check that AC is live ls the unit on Check the setting of the Auto Turn On switch Doesn t turn on with the Auto Turn On Audio Try the 12V trigger instead Check that input cables and speaker wires are secure at both ends Make sure the control preamp receiver is switched to the correct input If us
18. ower Requirement 110 120 V 220 240 V 50 60 Hz 3 watts standby 1000 watts full output Dimensions 17 Wide 16 Deep with connectors 2 High with feet 1 panel only 437 x 406 x 63mm 44 1 mm panel only Net and Shipping Weight XXXXXXXXX Rack Mount Accessory May be Purchased Separately RMK44 Before any home theatre component can be THX Ultra certified it must pass a rigorous series of quality and performance tests Only then can a product feature the THX Ultra2 logo which is your guarantee that the Home Theatre products you purchase will give you superb performance for many years to come THX Ultra2 requirements cover every aspect of the product including performance and operation IHX Ul Roky THX and Ultra2 are trademarks of THX Ltd which may be registered in some jurisdictions All rights reserved Note Specifications are subject to change or improvement without notice CONNECTION AND SETUP NOTES Notes We invite you to visit www parasound com for the most up to date information on your unit and to find out about other Parasound products Learn why Parasound has been a quality and value favorite of magazine reviewers sound professionals and listeners like you since we were founded in 1981 ye HALO PARASOUND G 3 eries PARASOUND NEWCLASSIC CUSTOM PARASOUND Parasound Products Inc 950 Battery Street San Fr
19. re reference OWNERSHIP REFERENCE INFORMATION Parasound Serial Number Date of Purchase I Name of Dealer Dealer Street Address Dealer Phone AC VOLTAGE INSTALLATION AND RACK MOUNTING O 115v 230v AC Voltage Selector Switch This switch is found on the chassis rear panel The 115V position of this switch is correct for North America most other regions require setting it to 230V Make sure the 115 230V switch is set for the correct AC line mains voltage before you connect the Model 2250 s power cord and before you install it The unit may be seriously damaged if this switch is set incorrectly Protective Cover AC Voltage e l 115V 230V 60Hz 50Hz Installation and Ventilation Requirements Install your Model 2250 away from heat sources such as heating ducts radiators or other heat producing components Always position it horizontally Observe the following ventilation guidelines when installing the Model 2250 in an equipment rack or any other enclosed space You should never install the Model 2250 in an unventilated equipment cabinet or compartment because hot air will not exhaust adequately to prevent overheating Air won t often circulate adequately in a cabinet or enclosure whose front and back sides are open pockets of intense heat can still develop around any heat producing equipment Therefore a ventilation fan is high ly recommended Allow a few inches of empty space on each side and abov
20. rent drawn by each of the com ponents you ve looped together Controllers can typically supply 150 mA at their trigger outputs Audio Trigger Sens Sensitivity Knob The Auto Turn On Audio Sensitivity knob adjusts the incoming audio level or the threshold required to turn on the Model 2250 lts 12 o clock position will be suitable in most cases To increase sensitivity for response to lower level audio signals turn the knob counter clockwise toward Turn the knob clockwise toward to decrease its sensitivity This will prevent spurious noise and switching transients in your system from false triggering the Model 2250 Note Plugging in the 2250 s AC cord for the first time will usually create an internal power surge that false triggers its Audio auto turn on even if there s no audio signal at its input jacks and it will remain on for 10 15 minutes after you switch it off This is normal Ground Switch Ground is the normal position for this switch If you hear background hum in the speakers connected to the Model 2250 try setting the Ground Lift Switch to its Lift position The Ground Switch disconnects or lifts the audio circuit ground from the chassis ground This often helps to eliminate audible hum that results from ground loops Ground loops are multiple ground paths such as the metal to metal contact with the panels or chassis of other components combined with the ground connections of the audio cables or even the
21. tically When a suitable voltage is applied to its 12V In input jack When an audio signal is present at the L and R audio Input jacks Note Vhen either automatic turn on method is selected the Model 2250 front panel Power but ton is disabled so that on off is determined solely by the triggering preamp or system controller 12V Position When the Auto Turn On switch is set to its 12V position the Model 2250 is turned on and off with an external 9V to 12V voltage from your preamp or controller When the external volt age ceases the Model 2250 will turn off immediately The 12V switch position disables the front panel Power button Man Manual Position When the Auto Turn On switch is in its MAN manual position the auto turn on function is disabled and the Model 2250 must be turned on and off manually with the Power button on its front panel Audio Position When the Auto Turn On switch is set to its Audio position the Model 2250 will be turned on whenever an audio signal is present at its Left and Right Input jacks After the audio signals cease the Model 2250 remains on for about ten minutes This prevents unintended turn off during pauses in your music or movies The Audio position of the Auto Turn On switch also disables the front panel Power button Note You will achieve more consistent auto turn on operation by using the 12V DC trigger if the Model 2250 is driving the surround center or rear channels At the beginning
22. zation RA number and shipping instructions from Parasound s Technical Department The RA number must be clearly marked on the outer carton Use the original factory packing materials and arrange adequate insurance to cover its value You must include a copy of your purchase receipt since this document establishes the validity of this unit s warranty Warranty repairs are only performed by Parasound or Parasound Authorized warranty centers when your purchase receipt is from a Parasound Authorized Dealer or Parasound Authorized Reseller Units Will Be Refused by Parasound Under the Following Conditions Unit was sent without the Parasound assigned RA number marked on the carton Unit was sent in an unsuitable shipping carton likely to have been damaged in transit Unit has inadequate packing unit likely to have been damaged in transit Unit was shipped collect for shipping charges We do not accept collect shipments Unit was shipped via the US Postal Service Unit was sent to an address other than the address instructed by our Technical Department oa fF WN Note The shipping address is not the same as Parasound s office address Warranty Repair Read your accompanying Parasound Limited Warranty carefully to understand the applicable rights and limitations This section provides instructions for obtaining repairs both for units covered under the Parasound Limited Warranty and for units or situations which are outside the Warranty U
Download Pdf Manuals
Related Search