Hafler TRM6.1CE manual Qualified Service Personnel Only, Woofer Crossover, Thermal Protection

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Woofer Crossover

Qualified Service Personnel Only

Woofer Crossover

The input signal at U4A pin 1 connects to the 3200Hz 2nd order low-pass filter at U112B. Approximately 2dB of additional gain can be added to this stage by adjusting R136 against the divider resistor, R137. The next stage is a 30Hz–60Hz switchable sub-sonic high-pass filter. This is followed by an adjustable low-frequency shelving filter which defaults at +6dB gain, according to the feedback resistors R129 and R134, and dividers R131 and R128. DS9–DS12 will switch in various reactive feedback networks to accomplish +4dB, +2dB, -2dB, or -4dB of gain shelving below 200Hz. The last stage is another 3200Hz 2nd order low-pass filter at U2A, which cascades with the previous filter at U112B to produce an overall 4th order slope of 24dB/octave for the woofer amplifier.

Thermal Protection

The thermal protection is activated, and shuts down audio operation, when the amplifier heatsink reaches an exces- sively high temperature. The voltage divider R22 and R23 establishes the reference voltage on pin 5 of U5B. The control voltage on pin 4 is established by the voltage divider TS1 and R25. TS1 is a NTC (Negative Temperature Coefficient) thermistor mounted on the heatsink. As TS1 warms and the resistance falls, the voltage on pin 4 rises. When the voltage on pin 4 exceeds the voltage on pin 5, the output on pin 2 goes low, shutting down the Soft Start switches Q8 and Q24, and lighting the CLIP/THERMAL indicator red.

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Contents Page to the above Directives and Standards EN60065 safety2-channel Audio Power Amplifier/Speaker Declaration of ConformityPower Rating PERFORMANCE SPECIFICATIONSDimensions Net WeightC A U T I O N NOTICE - IMPORTANT SAFETY INFORMATIONESPAÑOL ADVERTENCIA - INFORMACION DE SEGURIDAD IMPORTANTERANÇAIS ATTENTION INFORMATIONS IMPORTANTES DE SÉCURITÉDEUTSCH ACHTUNG - WICHTIGE SICHERHEITS - INFORMATIONENITALIANO NOTARE - IMPORTANTI INFORMAZIONI SULLA SICUREZZASERVICE REFERENCE TABLE OF CONTENTSINSTALLATION SCHEMATIC DIAGRAMSINTRODUCTION TECHNICAL DESIGN FEATURESAmplifie MEHSATransana MOSFET DevicesTweete Phase CoherentWave Guide Shielded MagnetTweeter Wave Guide Status LED Balanced Input Unbalanced Input Input Switch SensitivityFront Panel View Rear Panel ViewOPTIMUM INSTALLATIONLOCATION INADEQUATEINPUTFROM SOURCE Pin 1 = GND Pin 2 = + Pin 3 = GND XLR Balanced InputINPUTFROM SOURCE Pin 1 = GND Pin 2 = + Pin 3 = XLR Unbalanced InputNOTES Unless specified otherwise 1. All resistors in ohms SCHEMATIC DIAGRAM2. All capacitors in microfarads 3. Channel 1 only shown Qualified Service Personnel Only NOTES Unless specified otherwise 1. All resistors in ohms SCHEMATIC DIAGRAM2. All capacitors in microfarads 3. Channel 1 only shown Qualified Service Personnel Only SCHEMATIC Diagram PC BOARD LAYOUT +1dB Input OPERATIONINPUT SENSITIVITY +4dB Input+2dB with the same type and rating as indicated in the parts listBASS SHELVING +4dBCOLOR Power onPOWER SWITCH CLEANING and MAINTENANCEPART # PARTS LISTDESIGNATOR VALUERES 280 OHM 1/10W 1% MODEL TRM6.1CE 230 VAC 50/60 Hz TRM6.1 FUNCTIONAL BLOCK DIAGRAM CALIBRATION SERVICE REFERENCECIRCUIT OPERATION transana ImplementationTweeter Crossover Input CircuitThermal Protection Woofer CrossoverOn Indicator Clipping IndicatorPower Switch Wave Guide AssemblyTWEETER REPLACEMENT CAUTION Reconnect wires as indicated in each diagramTRANSFORMER REPLACEMENT Qualified Service Personnel OnlyAMPLIFIER REPLACEMENT CAUTION Reconnect wires as indicated in diagramWhat is NOT Covered SERVICE POLICY AND LIMITED WARRANTYLength of Warranty What is CoveredHAFLER A DIVISION OF MADE IN THE USALIT 11382 11/00 E.W.R