What is stereo?

There are now two system of high fidelity, monophonic (monaural) and stereophonic. Monophonic is a system that starts from one microphone and is fed through a single high fidelity set. Stereophonic is a double system. Two separate microphones are placed at different sides of the orchestra and two different systems are used to keep the two signals or channels separated. Two separate speakers are used, placed on different sides of you room. Stereo is much like 3-D photography, two slightly different sound reach your ears giving you a new dimension in sound.

H.H. Scott '59

Sony ST-J 88B tuner

The Sony ST-J88B is a quartz-locked frequency synthesized FM stereo tuner that just happens to be one of the very finest FM tuners we seen in years. It is probably the precursor of what to expect in the next generation of precision FM tuners, for the ST-J88B is, in fact, the next generation. The sound quality is exceptional, low frequency overload characteristics for more then 100% transmitter modulation usually a problem in synthesized tuners, is similiarly exceptional. Dual IF selectivity-normal (wide) and narrow is provided. Unlike the usual dual selectivity which is fair (wide) and very good (narrow), this tuner's selectivity is very good and outstanding; in the narrow mode we received full band of signals on alternate spacing, hearing many signals we did not even know existed (they are generally buried under alternate channel interference). The frequency readout is a digital display, tuning is in standard USA increments of 200 kHz. Seven memories are provided which remember the frequency, desired selectivity, muting on or aff, and auto stereo or mono mode.  Labels for every frequency which can be slipped behind the bezel above each memory selector, are provided. Other features include a signal strength indicator directly calibrated in dBf (received signal strength). There is no tuning device because the frequency synthesizer is always precisely on the station frequency. There are three tuning modes: Automatic - the FM band is scanned until a signal is received.  Manual - frequency can be changed rapidly or stepped on channel at a time. Memory - pressing one of seven buttons selects a preprogrammed frequency and all its operating conditions. The memories are non-volatile 9remembers programming) as long as the power cord is connected.

Input Level (for Full Limiting):  3,0 µV
Mono Hi-Fi Sensitivity (60 dB quieting):  9 µV
Stereo Hi-Fi Sensitivity (55 dB quieting):  65 µV
Stereo Frequency Response Range:  30 to 15,000 Hz
Stereo Frequency Response Limits:  0/ - 0,5 dB
Distortion - Normal Selectivity at Standard test:
Mono :  0,08% T.H.D.
Stereo :  0,08% T.H.D.
Signal-to-Noise Ratio (at Standard test level):  80 dB
Midband Stereo Separation:
Normal Selectivity :  40 dB
Narrow Selectivity :  50 dB
Alternate Channel Rejection (Selectivity):  very good
Maximum Variable Output:  3,5 volts (level at 100% modulation)
Maximum Fixed Output Level :  0,68 volts (at 100% modulation)
Alternate Channel Reject on Narrow Selectivity:  Outstanding
Mono Distortion narrow Selectivity:  0,3% T.H.D.
Stereo Distortion narrow Selectivity:  0,15% T.H.D.
Antenna Inputs:  300 Ω antenna, 75 Ω antenna (coaxial)
Dimensions (W x H x D):  480 x 80 x 370 mm
Weight:6,6 kg

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