SANSUI 661
¥ 69,800 (around 1972)
Commentary
This is a high-quality receiver developed using Sansui's accumulated technology.
Each circuit is integrated into three printed circuit boards, and ICs are used everywhere to eliminate troubles such as failure and improve reliability and durability.
In particular, the volume and switches of the control section of the preamplifier are directly mounted on the printed circuit board for reliable operation.
All stages are directly connected with pure complimentary service OCL system for the circuit configuration of the power amplifier.
The coupling capacitor that causes distortion is removed, and a differential amplifier circuit and ± 2 power supply are used.
The equalizer amplifier section uses a 2-stage direct-coupled circuit system using carefully selected low-noise transistors.
The tone control circuit is CR type.
The protective circuit consists of four short-cut fuses, plus an electronic circuit and relay to protect the speakers and power transistors.
This circuit also functions to prevent pop noise when the power is turned on.
The FM front MOS FET is used in the first stage of the FM front part, and it is combined with a linear frequency varicon to catch weak radio waves.
To maintain high stability, the power supply for the local oscillation stage is supplied from a dedicated stabilizing power supply to prevent frequency fluctuations and interference with other circuits.
Selectivity characteristics are also improved by using a two stage ceramic filter and a dedicated IC for the IF section.
The MPX section, which separates FM stereo signals into left and right, also uses an IC to ensure stable separation.
The AM tuner section uses a highly selective 2-element ceramic filter.
Two tape decks can be connected for recording and playback respectively.
In addition, DIN terminal is mounted.
It is equipped with a high filter switch that effectively cuts out unpleasant scratch noise and tape hissing in the high range of the record and makes it easier to listen.
Equipped with a loudness switch that maintains sound balance at low volume levels.
Audio muting is installed and -20dB attenuation is obtained when the switch is turned ON.
Equipped with a Stereo / Mono mode switch.
Equipped with an FM muting switch to eliminate inter-station noise.
The FM antenna input terminal has a balanced type of 300 Ω and an unbalanced type of 75 Ω.
Two speaker outputs are installed, and A/B/A + B is possible.
Two spare outlets and two large grounding terminals are mounted.
Model Rating
Type | FM/AM stereo receiver | ||||
Amplifier Unit | |||||
Rated output |
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Total harmonic distortion factor (at rated output) | Not more than 0.5% | ||||
Intermodulation distortion factor (at rated output) | Not more than 0.5% | ||||
Power Band With (IHF) | 15 Hz ~ 40 kHz | ||||
Frequency characteristic | 15 Hz to 30 kHz + 1 -1dB | ||||
RIAA deviation (30 Hz to 15 kHz) | ± 1.0 dB | ||||
Load impedance | 4 Ω ~ 16 Ω | ||||
Damping factor | 60 (8 Ω) | ||||
Hum and noise | Phono : 70 dB or more AUX : 80 dB or more |
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Input Sensitivity / Impedance (1 kHz) | Phono : 2.5mV/50k Ω (total harmonic distortion rate 0.5% or less) AUX : 100mV/50k Ω |
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Maximum allowable input | Phono:150mV | ||||
Output voltage | Tape Monitor Pin:100mV Tape Monitor Din:30mV |
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Tone control | Bass : ± 10 dB (50 Hz) Treble : ± 10 dB (10 kHz) |
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High filter | -10dB (10 kHz, 6dB/oct.) | ||||
Loudness | + 10 dB at 50 Hz, + 8 dB at 10 kHz | ||||
FM Tuner Section | |||||
Sensitivity (IHF) | 2.2 μ V | ||||
Total harmonic distortion factor | mono:0.5% stereo:0.7% |
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Signal-to-noise ratio | 60 dB or more | ||||
Capture ratio | 2.5 dB or more | ||||
Image Rejection | 55 dB or More (83 MHz) | ||||
IF Rejection | 60 dB or More (83 MHz) | ||||
Spurious response rejection | 60 dB or More (83 MHz) | ||||
Stereo separation | 35 dB or More (400 Hz) | ||||
Frequency characteristic | 30 Hz to 12 kHz + 1 -3dB | ||||
<AM Tuner Section> | |||||
Sensitivity (bar antenna) | 50dB/m(1kHz) | ||||
Selectivity | 28 dB or More (1 kHz, ± 10 kHz) | ||||
Image View Rejection | 80dB/m or more (1 MHz) | ||||
IF Rejection | 80dB/m or more (1 MHz) | ||||
<General> | |||||
Rated power consumption | 70W (210 VA max) | ||||
External dimensions | Width 444x Height 135x Depth 300 mm | ||||
Weight | 10kg |