The following audio systems are available for the 1999 Corvette:
Remote compact disc changer (available with ULO or UNO)
The following is included in each audio system:
The Electronically Tuned Receiver (ETR) utilizes a programmer and synthesizer to provide optimum sound reproduction. The ETR incorporates an electronic memory for preselected station and digital clock function. Reset the memory whenever the battery is disconnected.
Each system has a vacuum flourescent (VF) display that coordinates with the other instrument panel (I/P) displays. The Body Control Module (BCM) controls the dimming of the display based on inputs from the I/P cluster which reads adjustments of the I/P cluster dimmer switch (rheostat). The Light Emitting Diode (LED) and the back lighting of the radio face is done with incandescent light powered directly by the I/P cluster dimmer switch (rehostat).
The range of most Amplitude Modulation (AM) stations is greater than FM stations. This is especially true at night. The AM band tuning range is 530 kHz to 1710 kHz.
The Delco-GM/BOSE® audio system is an advanced automotive sound system that is tuned to the interior of the vehicle. The six speakers in four locations, two amplifiers in the forward speaker locations, and an amplifier incorporated into a signal processor are designed to deliver acoustically customized sound. The following are considered in the customization of the sound:
The result is a carefully calculated distribution of sound. The sound does not seem to come only from the speaker which results in a resemblance of a live concert performance.
When the system is turned ON the Bose® relay is energized through the radio receiver. The relay contacts close and apply current from the Bose® fuse to the two door mounted speaker/amplifier assemblies. This causes a slight delay from the time the system is turned on, until the sound is heard.
Loud bass volume is possible while maintaining sound clarity. Both forward speaker assemblies contain a specially designed amplifier and woofer (speaker) to assure clear sound reproduction at high volume levels. The following are some features of the system:
The Compact Disc (CD) player provides exceptional clarity and provides low background noise through digital reproduction. A selectable audio compression circuit processes the audio signal. This processed audio signal brings quiet and loud music passages into a more desirable listening range. This is especially useful in the automotive environment. When using compression, a demanding recording can be listened to without continually adjusting the volume.
The automotive environment can be a difficult one for sophisticated electronics. The CD player design takes into account many of the problems seen in automobiles. The player is designed to protect its optics from humidity and from excessive heat by automatically shutting down and ejecting the disc or displaying ERR. A special nylon filter across the disc opening protects the disc mechanism's optics from interference caused by moisture, dust and sunlight.
The loading system gently draws the disc into the mechanism. An ejected disc extends out almost halfway allowing the user to easily manage the disc. The loading system prevents damage to the disc if insertion of a second disc is attempted.
The use of a laser beam to read digital information means the disc will rarely wear out. There is no physical contact with the disc. An occasional skip due to rough roads will not damage the disc.
The remote compact disc (CD) changer is available with either the UL0 or the UN0. The remote (CD) changer is located in the cargo area in the center storage compartment. This CD changer features a 12 disc, removable magazine, and operation through the radio control head. The CD changer includes many of the quality design components found in the I/P mounted CD player (UN0).
The Delco-GM/BOSE® audio system uses ungrounded speakers. The Delco-GM/BOSE® system speakers and locations are described as follows:
The front location amplifiers equalize and drive the 8-inch woofers. The radio amplifier equalizes and drives both the front 3.5-inch Twiddlers™ and the rear 6.5-inch Twiddlers™.
The Corvette features a diversity antenna system designed to deliver the best radio signal reception possible.
Two antennas are used to form a diversity system. The primary antenna is attached to the rear lift window similar to a defogger grid. This antenna is used to receive both AM and FM signals. The secondary antenna is attached to the windshield in the same manner as the primary antenna. This antenna is used to receive only FM (diversity) signals. The antenna reception signals are sorted by a reception processing module. The module then sends the clearest, strongest signal to the radio control.
Multipath or signal flutter is the quickly fading in and out of FM radio signal reception. Multipath or signal flutter most often occurs in down-town areas or wherever large obstructions are present. A radio signal reflects off of buildings at various angles. When one signal crosses paths with a same signal (at a different angle) they will cancel each other out. The signal will be received and then not received very rapidly by a vehicle audio system. This causes a fluttering effect to be heard through a vehicle's speakers. With the Corvette diversity antenna system one of the two antennas will virtually always receive a strong signal and widely limit mutipath.
Both of the Corvette radios come with the THEFTLOCK® radio security system. THEFTLOCK® is designed to discourage theft of the radio by using a secret code to disable all radio functions whenever battery power is removed.
The radio feature THEFTLOCK® may be used or ignored. If ignored, the system plays normally and the radio is not protected by this feature. If THEFTLOCK® is activated, the radio will not operate if stolen.
When THEFTLOCK® is activated, the radio will display LOC to indicate a locked condition anytime battery power is removed. If the system loses battery power for any reason the radio must be unlocked with the secret code before it will operate.