*RARE* Vintage Carver Model C-1 Sonic Holography Preamplifier The Carver C-1 Sonic Holography preamplifier is basically a conventional high-quality control center. The C1 has separate bass and treble tone controls for each channel, with switchable turnover frequencies (8 or 2 kHz for the treble, 40 Hz or "loudness" for the bass). The control contours have been designed to provide maximum utility to the listener, with a limited amplitude of control range and asymmetrical boost and cut c...haracteristics. The Carver C-1 is 19 inches wide, 3-1/2 inches high and 10 inches deep. Inaddition to the four tone-control knobs on the front panel, there is a headphone jack (driven by its own amplifier), an input-selector knob, a small balance knob, and a large volume control. The program sources include two magnetic-phono inputs (phono 1 for conventional moving-magnet or moving-iron cartridges, and phono 2 with 25 dB additional gain for moving-coil cartridges).The phono 1 input impedance is 47, 000 ohms, with additional amounts of input capacitance (0, 180, or 390 picofarads) selectable by a slide switch in the rear of the unit. This makes it easy to match the input of the preamplifier to almost any phono cartridge. The phono 2 input is terminated by 39 ohms. The otherinput sources are identified as tuner, aux 1, and aux 2. The other front-panel controls are small rectangular push buttons. A group of six controls the Sonic Hologram, silences the speakers for headphone-only listening, and switches the power to the C-1. The Sonic Hologram controls, besides turning the circuit on and off, select different internal operating conditions whose significance is explained in the instruction manual. We received a Carver system on consignment from a customer. These items were bought in the early to mid 90s by her deceased husband. Approximately 7 to 10 years ago he packaged everything up in working order with bubble wrap, in boxes, and put it in a climate control closet. They have sat there until last weekend, at which time we unpacked the items and tested. Please understand that we are no way stereo or vintage audio experts. We were able to turn on all the components, we were able to plug this unit in and the light comes on. However, it does seem to NOT function properly. Bass and treble seem to not operate and speakers make a poping noise when you adjust the volume. THIS UNIT WILL NEED REPAIR!!!!!Thanks