User manual KENWOOD KAC-721

[. . . ] Do not remove caps from unconnected cables or connectors to prevent short circuits. · Connect the speaker cables to appropriate speaker connectors separately. Sharing the negative cable of the speaker or grounding speaker cables to the metal body of the car can cause this unit to fail. · After installation, check that the brake lamps, winkers, and wipers work properly. Installation Self-tapping screw (ø4 × 16 mm) Installation board, etc. [. . . ] As generally accepted positions for its installation, places such as inside the trunk, etc. (Optional) Length 0. 5m 1m 2m 4m 5m 6m Type RCA cable CA-2SL CA-12SL CA-22SL CA-52SL RCA cable (ø7mm) CA-3WL CA-13WL CA-23WL CA-53WL RCA cable (ø12mm) CA-5W CA-15W CA-25W CA-45W CA-65W 2CAUTION · Do not install the unit under the carpet. · Install this unit in a location which allows heat to easily dissipate. · Install the unit securely in a location that does not interfere with driving. 3 Controls Operations of the following control and switches are required in accordance with the center unit and speakers connected with this unit. FUSE(20A) POWER IN BATT 20 GND SERVO P. CON(REMOTE) SPEAKER OUTPUT SERVO FUSE(20A) 20 12 3 4 5 6 SPEAKER LEVEL INPUT LEFT RIGHT 15Hz OFF 25Hz INFRASONIC LPF INPUT FREQUENCY(Hz) SENSITIVITY(V) 100 70 50 200 150 1 2 3 4 0. 5 0. 3 LINE IN L GND R 5 0. 2 MONO POWER AMPLIFIER 7 8 90 ! @ 1 FUSE (20 A × 2) 2 Battery terminal 3 Ground terminal 4 Power control (REMOTE) terminal 5 Speaker output terminals As this unit accepts speakers with a minimum impedance of 2 ohms, connect speakers with 2-ohm or higher impedance to these terminals. 2CAUTION The rated input of the speakers should be no less than the maximum output of the amplifier. Otherwise malfunction may result. 6 SIGMA SERVO FEED BACK terminals (See p. 8) 2CAUTION Be sure to make proper connections to the SIGMA SERVO FEED BACK terminals. Incorrect connection may result in lack of sound output or other malfunctions. 7 INFRASONIC FILTER switch Ultralow frequencies that cannot be reproduced even by a subwoofer speaker do not become sound but become unnecessary oscillations, which affect the sound by causing distortion, etc. Setting this switch to "15 Hz" or "25 Hz" cuts the frequencies below the respective frequency. This improves the reproduction performance of the speakers by eliminating unnecessary oscillations which will not become sound. 8 LOW PASS FILTER FREQUENCY control This control adjusts the frequency band output from this unit. 9 INPUT SENSITIVITY control Set this control according to the pre-output level of the center unit connected with this unit, or to the maximum power output of the genuine-accessory car stereo. NOTE For the pre-output level or the maximum power output, refer to the "Specifications" in the instruction manual of the center unit. 15 10 0. 5 1 2 3 4 0. 3 25 5 (V) 0. 2 (W) 4 0 RCA cable ground lead terminal !· The power cable should be thick enough to supply the required current and connected directly from the battery. Speaker output cable terminal Connect the speaker output cables to these terminals. Lead terminal (Commercially available part) Speaker output cable Power terminal Pass battery and ground cables through supplied terminal cover and connect to respective terminals. After completing connections, fasten terminal cover over terminal bracket. Round terminal (Medium) Round terminal (Small) 7 Sigma servo feed back The sound reproduced through conventional amplifiers is distorted due to the counterelectromotive force produced in the oscillating system of the speaker. The counterelectromotive force is particularly high with the woofer which requires a large drive mass. The sigma servo connection reduces distortion caused by the counterelectromotive force by including the circuit up to the speaker terminals in the negative feedback loop. This makes it possible to drive speakers with more fidelity to the input signals and create a sharp bass sound image with few feeling of noise interference. NOTE The speaker cables and sigma servo cables should be distributed along the same paths. 2CAUTION · The extension of the negative feedback loop to include the speaker terminals makes it necessary to connect the sigma servo terminals correctly. Incorrect connection may result in sound degradation or other malfunction. If sound is not reproduced normally, check the connection of the sigma servo terminals, etc. · If the Sigma servo terminals are not connected, the sound may fluctuate or noise may occur. · When connecting speakers in a parallel configuration, use speakers with an impedance of 4 ohms or more. [. . . ] · When connecting speakers in a parallel configuration, use speakers with an impedance of 4 ohms or more. Connecting speakers with smaller impedance than 4 ohms will cause malfunction. · The rated input of the speakers connected to this unit should be no less than the maximum output of the amplifier. Be specially careful in this when connecting speakers in a parallel configuration. s Basic sigma servo connection s Series connection 2CAUTION Make this cable as short as possible. s Parallel connection (1) s Parallel connection (2) 2CAUTION The speaker cables connected to this unit should be thick enough to supply the current capacity of two speakers. 2CAUTION This connection is possible only when the speakers are identical and the speaker cables are also of the same type and length. s Simplified sigma servo connection In case any of the connection examples above cannot be used or if the speakers cannot be connected to the speaker terminals, connect them to this unit as shown in the figure. 8 Troubleshooting Guide What might appear to be a malfunction in your unit may just be the result of slight misoperation or miswiring. [. . . ]