Thank you for choosing a Harman Kardon Tunnel Cooled amplifier. This is a superb piece of high fidelity equipment that has been meticulously designed to provide you with many hours of enjoyment. Harman Kardon's Tunnel Cooled amplifiers are the result of an extensive engineering project to create the finest automotive highfidelity amplifiers available. These amplifiers provide superior performance, can operate under extreme environmental conditions, and are highly adaptable to various system configurations. This manual describes the features and capabilities of your new amplifier. In addition, it describes the proper methods for connecting your amplifier to your system. Please read this owner's manual and carefully follow the instructions for connection. Table of Contents Harman Kardon design philosophy ........2 TC600, TC300, and TC304 features .......3 introduction ............................................. 5 Installation precautions .................... .. 6 Charging system considerations .............7 Mounting location ................................... 7 System configurations............................. 8 Connecting the TC-series amplifier ........I I General information ............................ I I Power connections .............................. 13 Audio input connections ..................... 17 Speaker output connections ................. 18 Controls and operation ............................ 19 Application drawings .............................. 22 Series-Parallel and minimum impedance speaker connection ..............................29 Troubleshooting checklist ....................... 1 3 Fan reversal for multiple amplifier installations ......................................... 33 Specifications .......................................... 34 4 O 1990 Harman Kardon. Inc. 1 Harman Kardon design philosophy The TC Series amplifiers employ the key Harman Kardon design principles of highinstantaneous current capability (HCC), ultrawidebandwidth, low negative feedback, and fully discrete preamp and output circuitry. HCC (High-instantaneous Current Capa,bility) While reproducing dynamic music signals, the instantaneous impedances of nearly all loudspeakers drop to less than a third of the nominal rating. These low momentary impedances typically require three to six times more current from the amplifier than would a nominal Cohm resistive load. The TC600 amplifier can supply 100 amperes of instantaneous current, while the TC300 and TC304 can supply 50 amperes. This HCC provides control over the low impedance and fluctuating phase angles produced by normally operating speakers, ensuring that your speakers will be able to continually reproduce the entire dynamic range of music without premature clipping or current limiting. Bridgeable All TC Series amplifiers are designed to provide increased power into 2 ohms stereo or 4 ohms bridged. Unlike many lower-quality amplifiers, the TC Series amplifiers can be bridged for increased power. Stable, reliable operation in these higher power modes is assured by the TC Series' wide-margin Safe Operating Area (S.O.A.), which anticipates the toughest operating conditions. Ultrawidebandwidth Unlike conventional automotive amplifiers, the TC600, TC300, and TC304 can reproduce musical frequencies ranging from less than lOHz to more than 100kHz. This ultrawidebandwidth improves the accuracy of reproduction of transient signals and ensures phase linearity. Low negative feedback This design philosophy is used by the world's most exclusive amplifiers. It requires the highest quality internal components, and results in an extremely stable amplifier with unmeasurable TIM distortion and absolutely outstanding imaging characteristics. Fully discrete circuitry Rather than employing inexpensive integrated circuits, which reduce bandwidth and increase required negative TC600, TC300, and T C 3 0 4 Features feedback, the TC Series amplifiers use completely discrete (separate) electronic components for greatly improved linearity and less distortion. Ultrawidebandwidth combined with low negative feedback and fully discrete curcuitry maintains the correct harmonic and phase relationships in your music, providing superior imaging and definition. Transverse tunnel fan cooling Major heat-producing components in the amplifier are mounted directly to the center heat sink, localizing the area to be cooled. Harman Kardon's exclusive transverse tunnel cooled design employs a fan to eliminate heat directly from the heat sink, enabling the amplifier to remain cool to the touch and permitting installation in restricted spaces, such as under car seats. This exclusive design not only protects the preamplifier and power supply components from high temperatures, but also keeps dust and dirt from contaminating the inside of the amplifier, further ensuring reliable operation. Two-stage music-linked cooling fan speed The music link whisper fan operates inaudibly until the music volume rises, then goes to a higher speed for more efficient cooling without interference with your listening pleasure. The fan returns to its inaudible state between musical passages. Reversible fan For side-by-side multi-amp installations, the fan in each TC Series amplifier can be reversed, providing control over the direction of the cooling air flow. This enables you to prevent the warm air from one amp from being vented into the tunnel of the next amp. Designed and manufactured in the U.S.A. The TC Series amplifiers were designed with the aid of CADICAM computer systems at Harman Kardon's state-of-the-art industrial complex. The result is rugged, high-performance amplifiers employing only the highest-quality parts and materials, including double-sided fiberglass-epoxy printed circuit boards and high-current capacity bipolar transistors. Simultaneous stereo plus bridged mono operation For one-amplifier stereo satellite/mono subwoofer systems, the TC Series amplifiers can provide stereo and bridged mono operation simultaneously, eliminating the need for electronic crossovers and additional amplifiers. Fully regulated highcapacity power supply The high-capacity power supply is fully regulated, ensuring stable amplifier operation over a wide voltage range and cornpletely eliminating damage to speakers due to DC leakage. Balanced differential variable-gain inputs The input circuitry on TC Series amplifiers isolates signal cables from potential ground loops and radiated noise. In addition, it allows preamp or high-level (speaker) inputs to be directly connected to the amplifier inputs. 50Hz boost All TC Series amplifiers provide 50Hz boost equalization, enabling you to adapt your sound to your personal taste and compensate for acoustic limits inherent in the automotive environment. B+ and remote-on power noise filtering The TC Series amplifiers contain powersupply filters that effectively reject any power-supply-related noise, such as alternator whine. The 12-volt B+ main power input is filtered by a bank of capacitors and a large high-current inductor. Introduction This manual covers all three of the Harman Kardon TC Series amplifiers: the TC600, TC300, and TC304. Because of their clean, powerful design, these amplifiers can be used full-range or in specialized multi-amp systems as bass, midrange, or treble amplifiers. The TC600 and TC300 are two-channel (stereo) amplifiers that can be bridged into a single channel. The TC304 is a fourchannel amplifier that can be configured for four, three, or two discrete channels. All of the TC Series amplifiers are capable of operating in simultaneous stereo plus bridged mono mode, which allows for immense flexibility in system design and future upgrade potential. Please read this manual for information about system design considerations, connections, and operation. Before you begin your installation, determine your speaker configuration, wiring route, and location of the amplifier(s). Retain this manual for future reference. Important The TC Series amplifiers are professionalquality amplifiers that can be incorporated into any automotive system, from the simplest to the most complex. We strongly recommend professional installation of your TC Series amplifier to ensure that you obtain the optimum performance from your entire system. Warranty card Fill out the warranty card and suve your sules receipt. Your sales receipt is your proof of purchase and you will need it to establish the date on which your warranty begins. You will be required to show it if service is necessary during the duration of the Limited Warranty. Caution Listening at extremely loud sound levels can cause a temporary loss in your hearing acuity. Continued exposure can eventually cause this loss to become permanent. We caution you to be aware of the long-term effects of sustained high-volume sound. and we recommend that you use discretion when listening for extended periods. Installation precautions Disconnect the negative (-) battery terminal before beginning your installation, and do not reconnect it until all connections have been made and you are completely finished with your installation. As the very last step before reconnecting the battery, connect the positive power lead (sometimes referred to as B+) from the amplifier to the battery terminal. Important: To prevent serious shortcircuits that can do major damage (including potential for fire), you must install a fuse within 18" of the positive (+) battery terminal on the positive B+ power lead to the amplifier. (See the "Connections" section for information about fuse size). Make sure that the inlets and outlets for the amplifier's cooling fan are unobstructed. You must install the amplifier in such a way as to allow free air flow through the cooling tunnel to ensure that the amplifier will be able to dissipate its heat. Pay particular attention to the power ratings of the speakers you choose. Many speakers are not capable of handling the high power produced by the TC Series amplifiers. Match your speakers to the power ratings of the amplifier(s) you will be using, and never operate your speakers at higher levels than specified. Charging system considerations The TC600, TC300, and TC304 are highperformance amplifiers whose current demands place an additional load on your car's battery and charging system. Depending on the volume at which you are playing your system, the amplifier can draw an average of 20-40 amperes, and under certain extreme operating conditions, can draw up to 90 amperes in the case of the TC600. Because of the additional demand, the life of your car's battery and charging system may be shorter than it would have been before you installed your music system. You may need to install a heavy-duty charging system and a high-quality heavyduty battery to support the higher demands on the charging system. Depending on your listening habits, you may want to install a second battery and an isolation switching system. Consult your Harman Kardon dealer for professional assistance. Mounting location Harman Kardon's tunnel cooled design keeps your amplifier cool to the touch. enabling you to install it even in a very confined space, such as under a seat with limited clearance. Just be sure that you don't block or restrict the inlet or outlet to the amplifier's tunnel, so air can be circulated freely by the fan. This cooling method allows the amplifier to be positioned in any orientation (horizontal, vertical, upside down). Do not install your amplifier in a location where it would be exposed to rain, moisture, or direct sun, and do not allow dirt or foreign objects to enter the cooling tunnel. Use the amplifier itself as a template for marking the mounting holes. Before you drill mounting holes, make sure that you know what is located directly behind the panel you're drilling through (e.g., gas tank, brake lines, wires, etc.). System configurations This section describes some of the system configurations possible with the T C Series amplifiers. Low-level input to amplifier TC-Series amplifiers are most commonly used with a low-level (preamp) input signal from the head unit. A control on the T C Series amplifiers enables you to adjust the input signal level for optimum performance. (See the "Controls and operations" section for information on adjusting input level.) High-level input to amplifier All T C Series amplifiers can also accept a high-level (speaker-level) input signal from a head unit that has no preamp-level outputs. In this situation, the leads from your head unit that would ordinarily connect directly to your speakers are instead connected to the input of the TC Series amplifier. A control on the T C Series amplifier enables you to adjust the input signal level for optimum performance. (See the "Controls and operation" section for information on adjusting input level.) Normal stereo or four-channel full-range operation ("Full-range" means that a single ...