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 STR 2800

 For the audiophile looking for a budged-prieced quallity receiver, Sony's STR-2800 is the ideal solution. It offers many of the features you'd expect to find on a higher priced receiver, with enough power to drive most speakers. The STR-2800 delivers true stereo sound - the same quality sound that has made Sony famous.
RF front-end electronics unitized into tuning capacitor assembly.
FET-RF amplifier for high sensitivity and high interference rejection.
4-element, permanently aligned uni-phase IF filters and IC amplifier.
Phase-Locked-Loop IC stereo MPX stage.
Center station and signal strength meters
FM interstation muting
Easy toread frequency linear FM and AM dial scales with flywheel tuning knob
Directcoupled 2-stage phono equalizer.
Connections for phono and tape deck
Tape monitor switch
Loudness compensation switch
Separate bass and treble controls with click stop for flat position
Direct coupled, true complementary symmetry Darlington connected power output circuit
Outputs for 2 pairs of speakers
2 AC convenience outlets
Moder, low profile styling with 2 wooden side panels included.
Tuning.
When it comes to techno;ogical breakthroughs leave it to Sony to develop the most reliable circuitry built into every component they make. The STR-2800 is no exception, offering the latest in RF technology. This affords the listener crisp, clean FM reception with simple and accurate tuning. The FET RF amplifier provides higher sensitivity and higher interference rejection. High selectivity, good capture ratio and reduced multipath interference are the result of Sony's special 4-element, permanently aligned uni-phase IF filters and IC amplifier. And to guarantee that the STR-2800 produces life-like stereo separation, high stability and low distortion, the MPX stage utilizes a phase-locked-loop IC.


Perfect tuning couldn't be any easier - the STR-2800 offers a frequency linear tuning dial with flywheel tuning knob for both FM and AM listening. This receiver also offers a visible guide to accurate FM tuning with a center atation and a signal strength meter. The STR-2800 leaves no room for error - to assure the best possible FM reception there's  an FM interstation muting switch which minimizes interstation noise and static.
 Preamplifier and Control Sections.
The STR-2800 measures up to the high standards you'd expect from Sony - including accurate RIAA equalization, low noise and wide dynamic range provided by the direct coupled 2-stage phono equalizer. The human engineered front panel offers a variety of convenience features including an illuminated dial pointer, stereo indication light and signal strength meter. The back panel provides phono input jacks plus inputs and outputs for a tape deck. A tape monitor switch provides instant tape monitoring and instant tape/source comparison. Precise tonal compensation and a flat position are easily achieved with separate bass and treble controls with click stops. The loudness compensator boosts bass and treble levels, insuring that there is no loss in tonal fidelity when listening at alow levels.

Power Amplifier Section.
True complementary, Darlington connected power output circuit with direct speaker coupling provides the listener with wide-band response, low distortion and high stability operation. There are also outputs for two pairs of speakers with a front panel selector switch allowing for either individual or simultaneous listening of both pairs of speakers.
Specifications
FM Tuner Section
Antenna Terminals:  300 Ω (balanced);  75 Ω (unbalanced)
Usable Sensitivity (IHF '58):  2,0 µV
50 dB Quieting Sensitivity:  4,0 µV (mono);  50 µV (stereo)
S/N Ratio:  70 dB (mono);  68 dB (stereo)
Capture Ratio:  1,5 dB
Selectivity:  50 dB
Image Rejection:  45 dB
IF Rejection:  90 dB
Spurious Rejection:  75 dB
AM Suppression:  54 dB
Harmonic Distorton:
At 100 Hz, 1 kHz, 10 kHz - 0,2% (mono)
At 100 Hz, 1 kHz - 04% (stereo)
At 10 kHz - 0,8% (stereo)
IM Distortion:  0,2% (mono);  0,4% (stereo)
Frequency Response:  30 Hz - 15 kHz  =1 -3 dB
Stereo Separation:
At 100 Hz :  30 dB
At 1 kHz :  35 dB
At 10 kHz :  30 dB
RF Intermodulation:  55 dB
Power Amplifier Section
Continuous Power Output (RMS):  20 W per channel, (minimum RMS at 8 Ω form 20 Hz - 20 kHz with no more than 0m5% THD)
IM Distortion:  No more than 0,5% at 20 watts (no more than 0,3% at 1 watt)
Damping Factor:  25 at 8 Ω
Speaker Outputs:  2 (A,B) per channel
Headphone Output: 1 (8 Ω or 10 k Ω)
Residual Noise:  No more than 0,08 µW
Preamplifier Section
Input Sensitivity?Impedance:
Phono :  2,5 mV/50 k Ω
Tape :  250 mV/80 Ω
Phono Overload:  100 mV at 0,5% THD
Output Level and Impedance
Rec Out : 250 mV/4,7 k Ω
Total harmonic Distortion:  no more than 0,5% ata rated output
IM Distortion: no more than 0,5% at rated output
Frequency Response:
Phono :  RIAA standard ±1,0 dB
Tape :  10 Hz - 40 kHz  +0,5 -3 dB
Tone Control range:
Bass : ±10 dB at 100 Hz
Treble :  ±10 dB at 10 kHz
Loudness Compensation (at -30 dB level):
+8 dB at 50 Hz
+3 dB at 10 kHz
Signal-to-Noise Ratio (A-network weighted):
Phono :  69 dB at 2,5 mV Input
Tape :  90 dB at 250 mV Input
General
Semiconductors:
1 FET; 2 IC's; 36 transistors; 15 diodes
Power Requirements:  AC 120 V, 60 Hz,
Power Consumption:  95 W
Dimensions (W x H x D):  48s x 145 x 327mm (19-1/32 x 5-23/32 x 12-7/8 inches)

Weight:  9,5 kg (20 lbs 15 oz)

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