Sansui R-70 is an
AM/FM stereo receiver FTC rated 8ohms at 65 watts RMS per channel, 20 to 20,000
Hz, at a distortion no higher than 0,08% T.H.D. at any frequency
Features include a
stereo beacon, three-step LED FM center channel tuning indicator, five-step LED
AM/FM signal strength tuning indicator, leeft and right twelve-step LED output
power indicators calibrated 0; 0,005; 0,01; 0,02; 0,05; 0,1; 0,5; 1; 2; 10; 50
and 80 watts into 8 ohms, and automatic copy (dub) from/to either of two
recorders.
There are inputs for
magnetic phono, Aux, and two tape. Outputs for two speaker systems, two tape,
and phones.
Controls are
provided for tuning, concentric-clutched left and right volume (labeled
volume/balance), ganged bass, ganged treble, tape monitor/ copy selection,
input selection and speaker selection.
There are switches for high filter, loudness compensation, and FM muting (auto
for stereo, off for mono).
The FM antenna input
is 75/300 ohms. An internal antenna and external connection are provided for
AM. Switched and unswitched AC outlets are provided.
FM Tuner Section
Full limiting
measured 6 µV. The monophonic high fidelity sensitivity (60 dB quieting)
measured 13 µV. The stereo 55 dB quieting high fidelity sensitivity could not
be measured because unusually high pilot and MPX subcarrier leakage blocked the
test equipment at -38 dB. Full mute release was attained with 3 µV.
The stereo pilot and
subcarrier leakthrough is high and requires the use of an MPX filter when
recording with Dolby. This is no problem since all Dolby noise rduction systems
have the MPX filter; if yours is switchable make certain it is switched in.
At standard test
level the stereo frequency response measured +0,5/-0,4 dB from 20 to 15,000 Hz.
Monophonic distortion measured 0,18% T.H.D.; stereo distortion was 0,35%
T.H.D.. The Signal-to-Noise ratio measured 75 dB . Stereo separation was +40
dB. And selectivity was is good.
AM Tuner performance
- background noise level was higher than average.
Amplifier Section
performance
The power output per
channel at the clipping level with both channels driven 20 to 20,000 Hz into 8
ohms measured 43 watts RMS. The Frequency Response at 43 watts into 8 ohms
measured +0/-0,6 dB from 20 to 20,000 Hz
at a distortion no higher than 0,065% T.H.D. at any frequency.
The tone control
range measured +11/-12 dB at 50 Hz ; ±10 dB at 10,000 Hz
The magnetic input
hum and noise measured -58 dB; stereo separation was into the noise level.
The output power
meters are broadly calibrated - 1; 10; 100 watts, etc - and are reasonably
accurate at the calibration marks. The Frequency Response of the meters is
essentially "flat" 20 to 20,000 Hz, and can be relied on for tests if
the reference is one of the fast rise and a slow decay, providing a form of
semipeak indication.
Overall dimensions
are: 16-15/16" (wide) 5-13/16"
(high) 9-1-16" (deep)
Weight is 16,5 lbs