Sansui 661 FM/AM
Stereo Receiver
When Sansui
announced the price of this revolutionary new FM/AM stereo receiver, many
high-fidelity experts were greatly surprised, just as you were. The name Sansui
has long meant innovation and excellence in sophisticated audio electronics.
But it has also meant, usally, that any high-fidelity equipment bearing the
Sansui name also carried an expensive price tag. But now, thanks to a startling innovation
called CBM (Circuit Board Module) developed specifically by Sansui for finest
professional studio equipment, you can forget price and concentrate on the
outstanding Sansui quality and performance of the all-new 661.
This is a
budget-prieced stereo receiver that delivers "expensive" tonal
quality and performance. Its power amplifier is of a very advanced all-stage
direct-coupled OCL design providing RMS continuous power of 27 fully useable
watts per channel (total music power 110 watts) with a surprisingly wide power
bandwidth of 15 to 40,000Hz with very low overall distortion. Its MOS FET
equipped tuner and highly versatile preamplifier and control sections with two
stereo tape record/monitor circuits stereo AUX inputs and much more would
normally mean a far higher price tag. Check out the details of these and other
features of the Sansui 661 - your best bargain in Sansui stereo excellence.
Improved performance
and Reduced Costs with Sansui's CBM
Sansui's CBM
(Circuit Board Module) technique greatly increases electronic capability and
dependability, reduces wiring and size and significantly lowers the expense of
quality-controlled mass-production of highly sophisticated electronic circuits.
In tur, this means that the construction and chassis assembly of the 661 can be
performed in less time and at greater savings to you. The 661 incorporates four
CBM units, one each for its tuner, preamplifier, power amplifier and power
supply sections. Many ordinary receivers with considerably higher prices
require up to a dozen complicated and potentially troublesome circuit boards to
achieve the same results.
FM Fronted with FET
and Linear Variable Capacitor
A dual-gate
low-noise MOS FET (metal oxide semiconductor FET) and a frequency-linear
variable capacitor are used in the RF amplifier stage of the FM tuner in the
661. These combined with its 3-transistor converter stage composed of a local
oscillator and buffer circuit, each regulated by a separate constant-voltage
power supply provide excellent distortion characteristics, superior
signsl-to-noise ratio and very high FM sensitivity.
FM IF Amplifier with
Two Bi-resonator Ceramic Filters
The 661's
IC-equipped FM IF amplifier provides high station selectivity and reception of
both local and distant FM signals with exceptional clarity. The super-wide
selectivity bandwidth (1,1MHz peak to peak) and the sharp cut-off ceramic
filters in its circuits have vastly improved the dynamic range of the FM
section.
Newly Developed IC
Equipped FM Multiplex Demodulator
The 661's new FM
multiplex demodulator features a high-density IC for improved stability. Stereo
separation is better than 35dB and THD in stereo FM reception is less than
0,7%. An FM de-emphasis switch inside the chassis allows the 661 to be easily
converted for ideal reception of FM signals anywhere in the world.
AM Tuner Section
The enhanced
selectivity and sensitivity of the AM tuner in the 661 results from the use of
newly-developed, highly selective coils and a bi-resonator ceramic filter in
its IF amplifier stage. The tuner's design also eliminates the annoying whine
and boom of AM reception.
Stabilized FM/AM
Tuner Power Supply with Ripple Filters
Both the FM and the
AM sections of the 661 benefit from the elimination of ripples and fluctuations
in power supply thanks to a new stabilized supply technique. This results in a
greatly improved signal-to-noise ratio, as well.
Smooth-Tune
Mechanism and Linear Tuning Scale.
An attractive
easy-to-raed black-out dial panel of glare-free smoked glass is provided on the
661. Its tuning scale is FM linear, calibrated in equal sections of 250kHz each
for easy and fast reading. An oversized, brightly-lighted signal-strength meter
facilitates both AM and FM tuning. The smooth tune dial mechanism in the661 has
been engineered to incorporate an extra-large flywheel, special tension
mechanism and dial string of no-stretch/no-shrink polyester for stability under
all temperature and humidity conditions.
Direct Coupled
Low-Noise Phono Equalizer
Carefully-selected
low-noise silicon transistors are used in the phono equalizer amplifier of the
661 to provide excellent signal-to-noise ratio, minimum distortion and wide
dynamic range. Its phono overload capacity an important factor in any phono
equalizer for it determiners the ability of the unit to respond properly to all
signals no metter how strong or weak, is as high as 150mV RMS (420mV p-p),
allowing a wide dynamic range and reducing THD to less than 0,5%
More Precise Control
of Tone
The bass and treble
tone controls in the 661 are of the CR type in a carefully-engineered design to
minimize distortion and provide more precise control of tone coloration.
Two Tape
Record/Monitor Circuits with Reprinting and Stereo AUX
The 661 feature two
separate tape recording and monitor circuits. Thes are capable of handling two
stereo tape decks at the same time and permit tape-to-tape reprinting from
Tape-1 to tape-2 at the touch of a switch. Tape-1 can be connected either
through the pin-type jacks provided or through the DIN socket while Tape-2 can
be connected directly or coupled with a
4-channel adaptor (decoder). Separate tape monitor controls are provided on the front panel. The 661's stereo AUX
circuit also can come in handly for connecting an extra tape deck, cartridge
tape player, additional tuner or a number
of other units.
Independent Power
Amplification
The all-stage
direct-coupled OCL semi-complementary power amplifier provided in the 661
affords dependable and extremely clean stereo power to drive even the largest
of stereo speaker systems. The differential amplifier in the largest of stereo
speaker systems. The differential amplifier in the initial stage and the dual
plus/minus power supply system greatly improves the performance of this
advanced system. You have at your command a full 27 watts of continuous RMS
power per channel (into 8 ohms at 1kHz, both channel driven). Its power
bandwidth is surprisingly wide -from 15 to 40,000Hz- while its THD and
Intermodulation figures are both held to a low, low 0,5% or less.
Superior Power
Supply and Power Protection Circuits
Since the power
supply for the 661's power amplifier is entirely independent from those which
feed its preamplifier and tuner sections, two oversized capacitors of 4700µF
each and an extra large, closely-regulated power supply transformer see that
this supply remains stable and always available. The vital power transistors in
the all-stage direct-coupled OCL power amplifier are protected from damaging
power surges with several elaborate power protection devices. These include
four quick-acting fuses and a positive action relay circuit. The latter also
acts to protect your valuable speakers from damage or from the annoying
"popping" noise by providing a momentary delay between the time the
661 is switched on and the release of any signal to those speakers.
Other
SpecialFeatures of the 661 Receiver
Stereo/Mono Mode
Switch - which also by-passed FM multiplex demodulator when it is turned to
Mono position.
Balance Control - to
provide continuous balance of left and right channels.
Loudness Switch -
adjusts for low-volume listening
High Filter - to
eliminate tape hiss and record surface noise.
Stereo Headphone
jack - for private listening
FM Muting Switch -
to eliminate inter-station noise during FM tuning.
Terminals for Two
Pairs of Stereo Speakers - A and B with position for A,B or A + B
Two AC Outlets (one
switched)
Attractive
Champaigne-Gold Front Panel - with user-oriented control display
All-Wood cabinet-
-with cushioned no-mar feet.
Specifications
Audio Section
Power Output (at
rated distortion)
Music
Power (IHF) : 110 W (4Ω, 1kHz); 75 W (8Ω, 1kHz)
Continuous Power
Each
Channel Driven : 40/40 W (4Ω,
1kHz); 32/32 W (8Ω, 1kHz)
Both
Channels Driven : 27 +27 W (8Ω,
1kHz); 20 +20 W (8Ω, 20-20,000Hz)
Total Harmonic
Distortion (at rated power output):
Overall (fromAUX) :
less than 0,5%
Intermodulation
Distortion (at rated power output, 70Hz : 7,000Hz = 4 : 1 SMPTE method)
Overall (from AUX) :
less than 0,5%
Power Bandwidth
(IHF): 15 to 40,000 Hz
Frequency Response
(at 1 Watt power output)
Overall (from AUX) :
15 to 30,000 Hz, +1 -2 dB
Equalization (at
tape rec output): RIAA Curve (30 to
15,000 Hz ±1 dB)
Load
Impedance: 4 to 16 Ω
Damping
Factor: 60 (8Ω)
Channel Separation
(1kHz at rated power output)
Phono : better than
45 dB
Aux : better than 45
dB
Hum and Noise (IHF)
Phono : better than
70 dB
Aux : better than 80
dB
Input Sensitivity
and Impedance (1kHz for rated poer output)
Phono
: 2,5 mV/ 50 kΩ (Max. Input
capability 150 mV at rated distortion)
Aux :
100mV/50 kΩ
Tape-1
Play
Pin Jacks : 100 mV/50 kΩ
Rec/Play
DIN Socket : 100 mV/50 kΩ
Tape-2 (4-ch
adaptor)
Play
Pin jacks : 100 mV/50 kΩ
Recording Output
Tape-1
Rec Pin Jacks : 100
mV
Rec/Play DIN Socket
: 30 mV
Tape-2 (4-ch
adaptor)
Rec Pin Jacks : 100
mV
Switches and
Controls
Bass : +10 dB, -10
dB at 50 Hz
Treble : +10 dB, -10
dB at 10,000 Hz
Loudness : +10 dB at
50 Hz; +8 dB at 10,000 Hz
High Filter : -10 dB
at 10,000 Hz (6 dB/oct)
Tuner Section
FM Mode
Tuning Range: 88 to 108 MHz
Sensitivity
(IHF): 2,2µV
Total Harmonic
Distortion
Mono : 0,5%
Stereo : 0,7%
Signal-to-Noise
Ratio: better than 60 dB
Selectivity: better than 50 dB
Capture Ratio: 2,5 dB
Image
Rejection: better than 55 dB at 98 MHz
IF Rejection: better than 60 dB at 98 MHz
Supurous Response
Rejection: better than 60 dB at 98 MHz
Spurious
Radiation: les than 34 dB
Stereo
Separation: better than 35 dB at 400 Hz
Frequency
Response: 30 to 12,000 Hz; +1 -3 dN
Antenna
Input Impedance: 300Ω balanced (75Ω unbalanced)
AM Mode
Tuning Range: 535 to 1,605 kHz
Sensitivity (Bar
Antenna): 50 dB/m at 1kHz
Selectivity: better than 28 dB at 1MHz
Image Frequency
Rejection: better than 80 dB/m at 1Mhz
IF rejection: better than 80 dB/m at 1MHz
Others
Power Requirements
Voltage : 100,117,
220, 240 V 50/60 Hz
Consumption : 70 W
(rated), 210 VA (max.)
Dimensions (W x H x
D): 444 x 135 x 300 mm (17-1/2" x
5-3/8" x 11-13/16")
Weight: 10 kg (22,0 lbs ) Net; 12,4 kg (27,3 lbs) Packed