Kenwood Basic C2 Preamp #2 - $250 (Hubbard)

Kenwood Basic C2 Preamplifier #2

I'm selling two of these. See my other ad for the second unit.

This has low self-noise and distortion and wide frequency response. The phono preamp supports MM and MC cartridges and has 5 impedance settings.

Works great. Looks good, with the exception of minor wear on the top edge of the front panel and a couple of scratches on that panel. Minor scratches and scuffs on other sides of the case. Minor surface corrosion on parts of the cabinet that are not normally visible. The electronics do not appear to be corroded. Many hours of work have gone into bringing this unit into proper operating condition.

I will sell this with the matching Basic M1D power amp for $500 total (that one is listed separately as well).

I am an electrical engineer and have done the following work, mostly since August 2026:

• Replaced polarized electrolytic capacitors with Panasonic FC or FR (105°C), Panasonic film, or WIMA film, as appropriate.
• Replaced bipolar electrolytic caps with Nichicon Muse ES.
• Replaced NJM4560DN op-amp in phono preamp with NE5532 in a DIP socket. This has lower noise than the original and is less likely to be damaged by the 18.6V power supply (the 4560 can sometimes fail and take out the JFETs on the input).
• Bypassed the balance pot with solder jumpers and 180K metal-film resistors. The pot had failed and there is not a drop-in replacement; this is a typical mod on these units. The pot is still in place but its leads have been removed.
• Cleaned all switches and potentiometers with appropriate DeoxIT products.
• Removed, disassembled, and thoroughly cleaned the Tape and Source selector switches. Each has 52 solder joints and six moving contacts. This part of the project required several hours, but is essential to prevent crackling and dropouts. It is not sufficient to spray DeoxIT from the outside of the switch. The Phono selector is similar but easier to clean from the outside, and it isn't in the signal path, so it's less important to clean it thoroughly.
• Cleaned all RCA jacks, inside and out, with DeoxIT.
• Tested all inputs, outputs, and switch positions.
• Installed new Penn-Elcom heavy-duty rubber feet in the front two positions. The original parts had been removed by a previous owner.
• Cleaned exterior. 

 Partial specifications:

• Input Sensitivity/Impedance/Signal-to-Noise Ratio (IHF A Curve)
  • Phono MM: 2.5 mV/30 k, 47 k, 100 k ohms/88 dB
  • Phono MC: 200 µV/100 ohms, 200 ohms/70 dB
  • CD, AUX, TUNER, TAPE: 150 mV/47 k ohms/110 dB
• Signal-to-Noise Ratio Unweighted at 50 mW (DIN)
  • Phono MM & MC: 73 dB
  • CD, AUX, TUNER, TAPE: 79 dB
• Maximum Input Voltage for Phono MM: 200 mV, T.H.D. 0.002%
• Maximum Input Voltage for Phono MC: 15 mV, T.H.D. 0.002%
• Frequency Response
  • Phono MM & MC: 20 Hz - 20 kHz ± 0.3 dB
  • CD, AUX, TUNER, TAPE: 1 Hz - 350 kHz (– 3 dB)
• Tone Control
  • BASS turnover: 400 Hz: 100 Hz ± 10 dB
  • turnover: 200 Hz: 50 Hz ± 10 dB
  • TREBLE turnover: 3 kHz: 10 kHz ± 10 dB
  • turnover: 6 kHz: 20 kHz ± 10 dB
• Filter
  • Subsonic: 18 Hz, 12 dB/Octave
  • Low: 40 Hz, 12 dB/Octave
  • Subsonic + Low: 58 Hz, 12 dB/Octave
  • High: 8 kHz, 12 dB/Octave
• Transient Response
  • Rise Time: 1.0 µs
• Total Harmonic Distortion
  • CD, AUX, TUNER, TAPE
    • 20 Hz - 20 kHz: 0.001% at 1 V Output
  • Phono MM & MC
    • 20 Hz-20 kHz: 0.002%
• Output Voltage & Impedance
  • TAPE REC: 150 mV, 220 ohms
  • PRE OUT: 1,000 mV, 100 ohms
• Loudness Control
  • (at VOLUME - 30 dB): 100 Hz, + 6 dB
  • (at VOLUME - 40 dB): 100 Hz, + 9 dB

I can demonstrate this unit in Hubbard. I am available most evenings, and some other times, Monday through Saturday. Click the “more ads by this seller” link to see other items I’m selling.

Keywords: amp, amps, power amp, Rotel, Pioneer, Marantz, Sony, Denon, NAD, Sansui, Yamaha, preamplifier