I have a Bob Carver High Performance C-4000 Sonic Holography - Autocorrelation Preamplifier and a copied manual. The preamplifier is one of Bob Carver top of the line preamplifier. The preamplifier is fully loaded and even has a surround sound control which I have never used. The unit has so many features. This is one amazing preamplifier. I'm selling only because I went a different route with my Carver home setup. The preamplifier is fully functional and very clean with some very nice sound https://offerup.com/redirect/?o=ZmVhdHVyZXMuSXQ= has dual phono ,dual, dual aux, Tape 1 and 2, tone control, loudness, mono, trim control, Tuner, daul poweramps, external processor and much more I have some specs at the bottom of this literature thanks for reading $525 Description At its heart the C-4000 is a high performance console preamplifier with precise RIAA phono equalization, low distortion, high slew rate, wide dynamic range, and a high degree of control flexibility. But its similarity to other fine preamps ends there. The C-4000 goes far beyond mere accuracy and fidelity: it's goal is a dramatically higher degree of realism than has ever been achieved before in audio reproduction. Thus its Peak Unlimiter undoes the dynamic compression which makes many recordings and broadcasts sound canned. It's Auto Correlator noise reduction system strips away the veil of low level rumble and hiss which form a perpetual psycho acoustic barrier to realism in the reproduction of musical timbres. And its Time Delay and revolutionary Sonic Hologram Generator break through the limits of listening-room acoustics and the two channel stereo medium itself to provide a remarkably three dimensional you are there realism, with a sonic image which subjectively extends far beyond the loudspeakers in both breadth and depth. Specifications Frequency response: 1.5Hz to 60kHz Total harmonic distortion: 0.05% Gain: 60dB (MC), 35dB (MM), 20dB (line) Input sensitivity: 0.05mV (MC), 0.9mV (MM), 50mV (line) Signal to noise ratio: 75dB (MC), 81dB (MM), 98dB (line) Dimensions: 19 x 6.75 x 8.5 inches Weight: 5kg