Kenwood 9000 G (1975–1977)

The Kenwood 9000G was the top receiver in Kenwood's lineup in the mid-1970s. Collectors prize it mostly for the FM tuner section. The tuner is widely regarded as one of the best ever put in a receiver, and fmamateur.org describes it as the pinnacle of Kenwood's analog FM tuner development. The front end uses a 4-gang variable capacitance, dual gate MOSFET design, with four ceramic filters in the IF section and a stereo demodulator built around three ICs with a phase lock loop. It is quiet and sensitive. The monaural signal-to-noise ratio is rated at 100 dB, which fmamateur.org notes makes it the only receiver in the world with that figure. Tuning linearity and separation are reportedly excellent, and you can find the center frequency by feel thanks to a pronounced aurally detectable "sweet spot." The one complaint is that the FM muting threshold is a bit high, so you get an audible click when muting engages during tuning.

The amplifier is no slouch either. It's rated at 80 watts per channel into 8 ohms (20Hz-20kHz) with THD of 0.05%, and 100 W/ch into 4 ohms, though the Kenwood official PDF also lists 70W/ch at 8 ohms. The amplifier section uses four hybrid IC modules and a newly developed vertical differential type VMOS power transistor. All stages from input to final are DC amplifiers, with a slew rate of ±60V/µs. The power supply circuit doubles as the power amplifier, which is an unusual choice. A Japanese audio blog review translated on fmamateur.org describes the sound as pure and natural, with wide dynamic range and no coloration, and calls it a "sleep amplifier" whose quality surpasses 1980s digital tuner era models. Audio (June 1998, p.79) lists the Kenwood 9000(G) at $1500 in its classified section. The unit connects to Kenwood's "High Technology Series" and has a full logic F.L. (fluorescent) display.

Kenwood made two versions of this receiver: the 9000 and the 9000G. The 9000G was essentially a 9000 with improved FM tuner specs and a different faceplate. Sources give the model name both with and without the "G" suffix. The original price was $799.95. Dimensions are 20-3/4"W × 7"H × 16-1/4"D, and it weighs 43.6 lbs.

Known specs:

Power output: 80 W/ch RMS @ 8 ohms, 20Hz–20kHz; 100 W/ch @ 4 ohms (Kenwood official PDF also lists 70W/ch at 8 ohms)
THD: 0.05% at rated power
Phono frequency response: 20Hz–20kHz ±0.5dB (RIAA)
Tone control frequency response: 5Hz–100kHz ±1dB
Phono S/N ratio: 73dB; FM S/N (stereo): 70dB
FM usable sensitivity: 11.1 dBf / 1.9µV
Damping factor: 50
Speaker impedance: 4–16 ohms
Tone controls: Bass ±10dB at 100Hz; Treble ±10dB at 10kHz
Inputs: Phono, Tuner, Aux, Tape 1, Tape 2
Outputs: Speakers A/B, 2 tape decks, stereo headphone jack
FM antenna: 300 ohm and 75 ohm