Mackie-SRM450-spk-sm 维修电路原理图.pdf

SRM450Powered SpeakerSERVICE MANUAL1999,2000 MACKIE DESIGNS, INC.820-184-00RadioFans.CN 收音机爱 好者资料库Page 3 is interactiveGo To Bulletins2 SERVICE ON THIS EQUIPMENT IS TO BE PERFORMED BY EXPERIENCED REPAIR TECHNICIANS ONLYRadioFans.CN 收音机爱 好者资料库3CONTENTSIntroduction . 3Block diagram . 4Specifications. 5Overview . 6Safety test . 8Bias adjustment . 9Test points. 10Parts. A-1Fold-out SectionsSchematics and PCB layoutsMain board . 227-1INTRODUCTIONThis manual contains basic service information. It is essential that you have a copy of theusers manual as this contains the complete operating instructions.SERVICE TECHNICAL ASSISTANCEMackie Designs, Service Technical Assistance, is available 8AM - 5PM PST, Monday throughFriday for Authorized Mackie Service Centers, at 1-800-258-6883. Feel free to call with anyquestions and speak with a carefully-calibrated technician. If one is not available, leavea detailed message and a qualified Mackoid will return your call asap.DISCLAIMERThe information contained in this manual is proprietary to Mackie Designs, Inc. The entiremanual is protected under copyright and may not be reproduced by any means withoutexpress written permission from Mackie Designs, Inc. SERVICE ON THIS EQUIPMENT IS TO BE PERFORMED BY EXPERIENCED REPAIR TECHNICIANS ONLYClick on any item to open that page4Block DiagramINPUTTHRU1J151HI-PASSLOW CUTCONTOURCOMPRESSORTHRESHOLDCOMPRESSORSWEEPINGFILTERLO-PASSDELAY176uSHI-FREQ40-120 HzLO-FREQUENCYDRIVERTWEETLO-FREQAMPHI-FREQAMPSENSERESISTORBASS CONTROL SERVO LOOPWOOFPEAKLIGHTPEAKDETECTIONTHRESHOLDLPFTHRESHOLD+MID VDC+LO VDC+HI VDCTOROIDAL POWERTRANSFORMERFUSEPOWERSWITCHONOFF+15VDCSIGNALSENSESIGNALSENSEMUTEON/OFFCONTROLMUTEMUTEPOWERLEDSTHERMALLEDTHERMALSWITCHLOW ACVOLTS SENSETIMEDTURNOFFSIGNALLED5SpecificationsLow-Frequency TransducerDiameter300mm (12”)Voice Coil Diameter63.5mm (2.5”)Sensitivity (1W1m)98 dBNominal Impedance8 ohmsPower Handling300WFrequency Range50Hz 3000HzHigh-Freq Driver and HornDiaphragm Diameter44.5mm (1.75”)Exit Throat Diameter24.5mm (1”)Diaphragm MaterialTitaniumSensitivity (1W1m)106 dBNominal Impedance8 ohmsPower Handling150WFrequency Range1000Hz 20,000HzLow-Freq Power AmplifierRated Power300 wattsRated THD 0.1%Cooling:Convection ExtrusionDesign:Class G, Parametric ServoFeedbackHigh-Freq Power AmplifierRated Power100 wattsRated THD 0.1%Cooling:Convection ExtrusionDesign:Conventional Class ABSystem specsInput TypeBalanced DifferentialInput ImpedanceLine: 20k ohmsInput ProtectionRFI and level protectedSensitivityLine: +4 dBu (centered)Mic: 36 dBuMaximum Input LevelLine: +22 dBuLow-Cut Frequency75Hz, Second-order filterEQPeaking +3 dB 55Hz,+3 dB 20kHzOver-Excursion ProtectionSecond-Order High-PassFilterThermal ProtectionAmplifier shutdown, auto-resetLow-Line Voltage Shut Down: 60% Nominal lineAcoustic Freq Response: 45Hz 20,000HzLow-Freq 3 dB Point:55HzMaximum SPL 1m:123 dBLow-Freq Crossover:24 dB/octave, time offsetcorrectedHigh-Freq Crossover:24 dB/octaveCrossover Frequency:1600HzDriver ProtectionIndependent LF and HFcompressorsLow-Freq Roll-Off:Dynamic-signal level de-pendentAccessory Interface15V DCOperating Temp Range10C - 45C (14F - 113F)Line Input PowerUS120V, 60HzEurope230V, 50HzJapan100V, 50/60HzDisclaimerSince we are always striving to make our productsbetter by incorporating new and improved materi-als, components, and manufacturing methods, wereserve the right to change these specifications atany time without notice.1999 Mackie Designs Inc.All Rights Reserved.6OverviewThe SRM450 is an active two-way loudspeaker system capable of extremely high soundpressure levels.The TransducersThe SRM450 active monitors feature a 12” high-power low-frequency woofer and a 1.75”titanium diaphragm high-output precision compression driver. This highfrequency driver is mounted on an acoustically non-resonant exponential waveguide,providing a wide, controlled dispersion and precise reproduction of the critical uppermid-range and high frequencies. The result is an unbelievably smooth off-axis responsethat allows everyone in the audience to experience the same high-resolution audio nomatter where they are seated.Each driver has been specifically designed by our engineers for optimum performance inthe lightweight high-strength cabinet.FR Series Power AmplifiersTo power these beautiful things, each SRM450 includes two of our acclaimed FR Series“Fast Recovery” power amplifiers. Our exclusive design uses low negative feedback, yetallows the amplifiers to maintain low distortion and stability and to quickly recover whendriven into clipping.The amplifiers include the following features:The low-frequency amplifier produces up to 540 watts peak (300 continuous)before clipping.The high-frequency amplifier produces up to 150 watts peak (100 continuous)before clipping.Each amplifier has its own compressor circuit that acts when the input signal is largeenough to cause clipping, distortion and excessive voice coil heat. The compressor willautomatically decrease the input signal to a safe level. The compressor in the low-frequency amp works independently from that in the high-frequency amp.The low-frequency amp uses a servo feedback loop which senses the current flowing inthe woofer coil. This controls the low-frequency response and maintains low distortion athigh output levels.The low-frequency amplifier also has a sweeping filter. This will automatically move thelow cut-off frequency up or down depending on the amplifier output. For example, if theamplifier is below clipping, the low-frequency cut-off point is 55Hz. As it approachesclipping, this shifts up smoothly to 120Hz, providing more power reserves and lessdistortion before clipping. This happens quickly and continuously, protecting the ampliferand the woofer and reducing any noticable distortion.Warning: Although the amplifiers have these protection circuits, you must still make surethe PEAK light is not blinking often or continuously. If it is, turn down your mixer faders, orpreamplifier gain, or turn down the SRM450 LEVEL control.7The CrossoverThe built-in electronic crossover is a 24 dB/octave Linkwitz-Riley design.Although more expensive than other crossover designs, the benefits provided by theLinkwitz-Riley design have been well documented. These benefits include:Absolutely flat frequency response throughout the bandpass, without the characteristicripple near the crossover point exhibited by other designs.The sharp 24 dB per octave roll-off of the filters ensures that the transducers arentreproducing frequencies outside of their capabilities.The acoustic sum of the two driver responses is unity at the crossover frequency, resultingin perfect power response.Our heroic engineers have worked carefully to ensure that the SRM450 also providesperfect phase response. This diligence has yielded phenomenal accuracy, even if you arestanding 20 feet away.The CabinetThe SRM450 cabinet was designed to be the strongest molded composite cabinet on theplanet. This material is as strong as concrete, and rigid enough to prevent unwantedvibrations in the cabinet. It has built-in fly points for hanging, and a socket in the bottomfor mounting on a tripod stand. Although it is an exceptional choice for installed soundsituations, its light weight and durable finish also make it ideal for portable sound systemuse. The asymmetrical trapezoidal design of the cabinet makes it easy to use as a floorwedge for stage monitor applications.8You must perform the following leakage test before returning the unit to your customer.Take every safety precaution to protect yourself while doing this test.1.Make a small loading RC circuit as shown in the diagram below, and connect the ACvolt meter between the AC power source ground and any exposed metal on the unitunder test.2.Connect the unit under test to an AC power source using a ground-lift adaptor, leavingthe units safety ground floating. Turn the unit on.3.The meter reading should be less than 750mVAC (note: this is equivalent to 0.5mA ofleakage current).4.Flip the plug over in the receptical so the hot and neutral are swapped.Verify that the reading is still less then 750mVAC.5.If either reading is greater than 750mVAC, then you must investigate and repair the unitbefore returning it to your customer.Safety test9Bias adjustment1.Place the SRM450 on its side so that the heatsink fins are horizontal.2.Connect the power cord and turn it on, with no inputsignal applied. Make sure that the TIMED TURNOFF switch isOFF.3.Let it sit this way for an hour or more to allow the heatsinktemperature to rise. You can play music through to speedthings up. If you have a thermometer, the bias adjustmentprocedure is best done when the heatsink temperature is 45 to50 deg C.4.Turn off the SRM450 and remove the power cord.5.Remove the complete amplifier/heatsink assembly from the plasticspeaker case but leave all wires connected, including the speaker wires.Support the amplifier so it can be safely turned on again.6.Replace the power cord and turn on the amplifier and take care not to touch anyexposed live AC components.7.No input signal is applied.8.Low frequency amplifier bias adjustment:While the heatsink is still warm, measure the DC voltage across the 2 pins of J21. AdjustR202 until a reading of 4mV to 4.5mV is reached. See sheet 2 for the location of J21 andR202.Important: When finished adjusting, secure R202 with a small drop of paint, such as nailvarnish.9.High frequency amplifier bias adjustment:Measure the DC voltage across the 2 pins of J20. Adjust R212 until a reading of 4mV to4.5mV is reached.Important: Secure R212 with a small drop of paint.10. This completes the adjustment procedure. Reassemble and perform a full test.The Amplifier Bias of every SRM450 must be carefully adjusted as follows.10LOW FREQUENCYBIAS TEST POINTLOW FREQUENCYBIAS ADJUSTMENT POTHIGH FREQUENCYBIAS TEST POINTHIGH FREQUENCYBIAS ADJUSTMENT POT+80V+15 VDC-15 VDC-80V+45V-45VA-1PART# DESCRIPTION PAGES090-132-xxMaster Parts A-2080-136-00Cabinet subassembly A-3055-227-00Main Board A-4SRM-450 PARTS LISTParts Numbering guide040-Cables055- Finished PCB Assy100- Pots and resistors200-Capacitors300- Semiconductors400- Jacks/Connectors500-Switches510- Fuses550- Chassis Metalwork600-Transformers601-Inductors610- Wires and Cables640- AC line cords700-Hardware760- Knobs/Plastic770-Fans790- Misc./Packing800- Printed Material860-EPROMComponents noted with this symbol shall be replaced only by the component specified.This is required to maintain product safety.Click on any item to open that pageA-2PART NO. DESCRIPTION REV QTYNOTES090-132-00 SRM450 120V 9 A3 1080-112-00 SA HTSK/XFMR/BD 12IN SPKR B1 A21080-112-01 SA AMP SRM450 230V A2 A2 1055-227-00-02 PCB ASSY SRM450 AMPLIFIER 2C A2 1 See Page A-4080-137-00 SA SW SRM450 B 1080-138-00 SA XFMR 600-034-00 B A1 1 For 120V units080-138-01 SA XFMR 600-034-01 A A1 1 For 230V units080-138-02 SA XFMR 600-034-02 A A1 1 For 100V units510-013-00 FUSE SB 7A 5X20MM 250V A 1 For 120V units510-011-00 FUSE SB 4A 5X20 250V IEC B 1 For 230V units510-024-00 FUSE SB 8A 5X20MM 250V A 1 For 100V units550-398-00 SCRN BACK PNL MAIN SRM450 A 1550-460-00 SHLD M6 PC SRM450 A 1550-488-00 SHLD .015 M6X 4 3/4 ID 1 A1 1551-071-00 PNT EXTR HTSK SRM450 A 1700-010-04 TF 6-32X3/8 PHP BLKZC A 9700-010-06 TF 6-32X1/2 PHP BLKZC A 4700-011-00 MCH 4-40X1/4 BTNSKT BLKOX A 3700-028-00 SEMS 6-32X1/4 PHP BLKZC B 8700-034-02 SEMS 4-40X3/8 PHP BLKZC A 4700-113-00 BOLT CAR 5/16-18 2IN STL A 1701-016-00 5-20X5/16 PHPII TYP B BLK A 4705-001-00 KEPNUT 6-32 A 2705-005-00 NUT LOCK 4-40 A 4705-018-00 NUT HEX 5/16-18 (GD-5) A 1710-005-00 WASHER INT STAR NO.6 BLK A 4710-017-00 WASH SPLTLCK 5/16 HEAVY A 1710-024-00 WASH FLAT 5/16 HARD (USS) A 1720-007-00 TAPE DS 30MIL X 1.0W URTH A AR (as required)730-001-00 THERMAL JOINT COMPOUND A AR730-025-00 LOCTITE 222 A AR740-001-00 TYRAP 3-1/4L A 1740-003-00 TYRAP 8IN BLK A 3760-018-00 KNOB 11MM DARK GRAY B 1780-052-00 INSULATOR PCB SRM450 A 1780-111-00 WASH RUB (W/TRANSFORMER) A 1080-136-00 SA SRM450 CABINET A 1 See next page (A-3)092-903-00 LC IEC SJT 1250W 10A/125V A 1640-002-02 LC JAPAN 12A 125VAC 8FT C 1 Linecord for 100V units550-397-00 PLATE COVER SRM450 A 1701-021-00 6X3/8 PHP PLASTITE BLK A 4730-035-00 ACTIVATOR NO.2287 NORTON A AR760-115-00 SIDE HANDLE GRIP SRM450 A 2760-116-00 PLASTIC SIDE HANDLE A 2800-139-00 SLEEVE SRM450 A 1820-158-00 OWN MNL SRM450 A 1Master Parts List 090-132-xxComponents noted with this symbol shall be replaced only by the component specified.This is required to maintain product safety.247bA-3PART NO. DESCRIPTION REV QTYNOTES055-280-00 PCB ASSY LED 1080-156-00 SA CABLE PCB LED BLK/WHT 1080-157-00 SA SUPPORT DRIVER THROAT 1080-158-00 SA HARNESS BLU & BLU/BLK 1080-159-00 WIRE YEL WOOFER 1490-025-00 COMP DRIVER 1 Comp driver490-042-00 WOOFER SRM450 1 Woofer490-047-00 SRM FRONT CASE MRB 1 Front case490-048-00 SRM REAR CASE MRB 1 Rear case490-052-00 POLE MNT KNOB 1490-053-00 FOAM D BLK&WHT 1550-408-00 TOP HANDLE PA SPKR 1 Top handle550-410-00 GRILL 12IN SPKR ACTIVE B 1 Grill700-123-00 SCREW SIDE HDL GRIP MNTG 4700-124-00 SCREW HDL MNTG TO CASE 4700-125-00 SCREW WOOFER 8701-021-00 6X3/8 PHP PLASTITE BLK A 4701-026-00 SCREWS FOR CASE 17701-027-00 SCREW BACK PANEL 12701-028-00 SCREW FEET GRILL CD-THR 13701-029-00 SCREW PCB ASSY LED 1705-031-00 FLYING HW INS NUTS GALV 8705-032-00 FLYING HW INS NUTS BLK 2710-049-00 WASH HDL MTNG TO CASE 4710-050-00 WASH FLAT WOOFER 8710-051-00 FLYING HW INS WASH GALV 8710-052-00 FLYING HW INS WASH BLK 2712-068-00 FLYING HW INSERTS 10712-069-00 GROMMET LEAD WIRE 1750-015-00 FEET 3760-115-00 SIDE HANDLE GRIP SRM450 A 2760-116-00 PLASTIC SIDE HANDLE A 2780-135-00 GASKET WOOFER SRM450 1 Woofer Gasket780-138-00 FOAM DA COMP DR TO CASE 1780-139-00 FOAM D COMP D TO THROAT 1780-140-00 GASKET FOR SPEAKER 1790-010-00 BAG 20 X 7 X 48 4MIL GUSS 1800-141-00 BOX SRM450 1810-088-00 CARDBD BTTM SRM450/C300 1810-089-00 TRIANG INS SRM450/C300 1840-249-00 LBL LOGO SPKR FRONT A 1840-250-00 LBL LOGO SPKR RUNNING MAN A 1840-251-00 LBL SPKR PWR ACTIVE A 1840-314-00 LBL INSERT COVER SRM450 A 10Cabinet Subassembly 080-136-00A-4055-227-00 Main pcb assembly227cPART NO. DESCRIPTION VALUE REFERENCE DESIGNATORS040-311-00 DIS 18GA 1010 GNYL 5 HKLG P1100-084-00 RES CF .125W 5% 30K OHM 30K 5% R189 R215105-464-00 RES MF .125W 1% 60K4 OHM 60K4 1% R177 R203110-025-00 RES CF .25W 5% 100 OHM 100 5% R266115-361-00 RES MF .25W 1% 5K11 OHM 5K11 1% R156 R238115-364-00 RES MF .25W 1% 6K04 OHM 6K04 1% R25 R45 R78115-389-00 RES MF .25W 1% 10K0 OHM 10K0 1% R256115-418-00 RESISTOR CF 20K0 1% 20K0 1% R220 R222120-097-00 RES MO .5W 5% 10K OHM 10K 5% R261 R263-264122-081-00 RES MO 2W 5% 2K2 OHM 2K2 5% R254-255123-009-00 RES MO 3W 5% .22 OHM 0.22 5% R183 R240 R249 R260123-056-00 RES MO 3W 5% 20 OHM 20 5% R248 R262125-030-00 RES WW 5W 5% .22 OHM .22 5% R152 R201130-021-00 POT TRIM 10KB HORIZ 10KB R62 R267130-038-00 POT TRIM 500B HORIZ 500-B R202 R212130-078-02 POT 12MM DUAL 10KZD REVLOG 10KZD R265140-025-00 RES TF