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





Pioneer SX-880 receiver

Stereo Receiver with DC Power Amplification

DC Power Amplifier

"DC with a Difference" Power Amplifier Pioneer Solves the TIM Problem

The adverse effects of Transient intermodulation Distortion, or TIM, are devastating to the delicate waveforms which make up musical signals on their way to your speakers. TIM accounts for the "muddy" quality of the music you reproduce through conventional audio amplifiers, those with the old-fashioned AC circuit configuration using capacitors in their NFB or Negative Feedback loops.

Pioneer's "DC with a Difference" power amplifier circuity found in our best amplifiers and receivers solves the TIM problem. Other forms of distortion, too, are eliminated by the fact that we use no phase-dalying capacitors in the NFB loops, but - and this is important - we retain the capacitors in the inputs.

Advantages include;

Connected speakers are protected from DC-caused breakdown without the assistance of an overly elaborate (and unnecessarily expensive) special protection circuit.

Tonal quality is not harmed by DC in any way.

Our use of selected input capacitors ensures that tonal quality is maximized at all times over the widest possible frequency range.

Low-frequency transient current, generated inside the preamp section when the unit is turned on and off, is eliminated. Noise is entirely avoided.

Musical quality is never threatened when you play warped records.

 

Power Amp Circuitry, Supply and Protection

The power output section circuitry of the SX-880 has a current-mirror-loaded differential amp input and a constant-current-loaded, Darlington-connected, direct-coupled OCL output. Two discrete power transistors in each channel are supplied from a large transformer and two 15,000 µF capacitors to ensure plentiful reserve for maximum dynamic range. A large heat-sink, and a newly-developed Pioneer IC (PA-3004), are among the sophisticated touches which guarantee stability and full protection. The IC, in fact, not only safeguards speakers and circuitry from abnormal DC potentials at amp output terminals, it serves also as a muting device to and power on/off noise. The circuit is entirely self-restoring

 


Twin Power Meters: Instant-by-Instant Readout of Left/Right Chanel Power Delivery

Here are two functional meters which more definitely , not "just for show". You can drive your speaker systems at their best-sounding, best-performing levels by observing the logarithmically-compressed scales of the twin power meters on the SX-880. they display instant-by-instant readouts of the power output in each channel over a range of 0,01 to 120 watts each.

 

Pioneer-Exclusive IC for Stereo Demodulator

The PA-101A, an integrated circuit with astonishing capabilities, is another example of how Pioneer's leadership in hi-fi technology benefits you. In the FM section of the SX-880, this remarkable IC serves as a part of the PLL stereo multiplex demodulator.

But it also contains a very special device to automatically cancel the 19 kHz FM pilot signal; if an ordinary filter were used for this job, it would severely limit frequency response in the highs. So, instead of the typical 15 kHz or lower cut off, you'll hear clean highs with flat response up to 20 kHz for truly hi-fi results.

 

Low-Pass Filter with 23 kHz Cut-Off

Since all 19 kHz signal components are cancelled by the Automatic Pilot Signal Canceller, mentioned above, the low-pass filter following the IC is required to filter out only sideband components. In the 23 kHz to 53 kHz range, on the main carrier. Thus audio range is never squeezed nor lopped off at the top.

 

High FM Sensitivity; Not Just a Promise

The high 1,8 µV sensitivity of the FM section in the SX-880 is not just a meaningless specification, nor is it an empty promise. You'll pull in the station you want no matter how distant its transmitter or weak its signal, and enjoy the highest possible sound quality in the bargain. Circuitry in the FM front end includes a three-transistor configuration with a dual-gate MOSFET in the first stage.

 

FM IF Amplifier; Excellent Phase Characteristics

Another state-of-the-art. IC is used to achieve sufficient gain and beter limiter characteristics in the FM IF amplifier of the SX-880. it is circuited between three two-pole ceramic filters which have excellent phase characteristics. One indicator of the superior performance of this design is found in the high capture ratio of 1,0 dB or better.

 

Superior Distortion/Noise Specifications for Better Listening

The three important functions of the Pioneer-exclusive IC in the FM tuner of the SX-880 are IF amplification, muting and FM discrimination. Proof of the ICs extraordinary performance is found in the listening. Distortion is a low 0,07% (mono), 1 kHz, 65 dBf. And the noise factor, expressed as an 80 dB or better Signal-to-Noise Ratio at 65 dBf, cannot be bettered in any other receiver in this price range.

 

Pleasing AM Sound; High Sensitivity and Signal-to-Noise Ratio

Pioneer has lowered noise, sharpened sensitivity and cleaned up low-frequency response to make AM pleasantly listenable. An IC and a newly-designed AM ferrite bar antenna are among the touches which raise sensitivity to 300 µV/m and the Signal-to-Noise Ratio to an excellent 50 dB.

 


Low Distortion Preamp

Phono Equalizer; Definitely High Fidelity Performance

Hi-fi purists still insist that the disc record is the only "true" musical medium for wide dynamic range and realistic Frequency Response . Reproducing disc-recorded musical signals on the RIAA

Equalization curve over the widest possible frequency range is possible in the SX-880 thanks to the use of a voltage-proff IC, very low-error resistors and capacitors and other top-quality parts. Phono overload is 200mV at 1 kHz, with only 0,05% T.H.D. or less.

 

Capture Ratio Tone Control: "OFF" Positions Ensure Ruler-Flat Response

The Bass and Treble tone controls each have a center-clicked position marked "OFF" which doubles as a "defest" to ensure a ruler-flat response. The tone control amp is of the Capture Ratio type for ideal response, low noise and low distortion. There is also a Capture Ratio-type Subsonic Filter with a low-cut frequency of 15 Hz, 6 dB/ot.

 

A Complete Music Control Center

You'll appreciate the versatility of the SX-880 all the more with use. The simple-to-operate controls include:

Tape Monitor/Duplicating switches, permitting monitoring of Tape-1 or Tape-2, dubbing from either deck to the other (even as you listen to Source), and direct recording into either or both decks from Source

Speaker Select switches, independent off/on pushbuttons for System A and B

FM Muting switch to end inter-station tuning noise

Mode Switch for Stereo or Mono

Balance switch has click-stop in center

Loudness switch for natural response at low volume

Twin Tuning Meters, in addition to Left/Right-channel Power Meters, for accurate AM/FM Tuning

LED indicators for AM, FM, Phono, AUX, and Stereo FM

Attractive Walnut-Grained Vinyl Cabinet

 


Specifications

Amplifier Section

Continuous Power Output: 

60 watts per channel at 8   (20 - 20,000 Hz, 0,05% T.H.D.)

60 watts per channel at 4  (20 - 20,000 Hz, 0,08% T.H.D.)

Total Harmonic Distortion no more than 0,05% (continuous rated power output)

Intermodulation Distortion:  no more than 0,05% (continuous rated power output)

Damping Factor: 30

input Sensitivity/Impedance:

Phono :  2,5 mV/50 k

AUX: 150 mV/ 50 k

Tape Play 1, 2 :  150 mV/50 k

Phono Overload Level:  200 mV ( 1 kHz  T.H.D. 0,05%)

Output Level/Impedance

Tape Rec 1, 2 :  150 mV

Speakers:  A, B, A +B

Headphones:  Low impedance

Frequency Response

Phono (RIAA EQ) :  20 to 20,000 Hz ±0,2 dB

AUX, Tape Play :  5 to 80,000 Hz +0 -1 dB

Tone Controls:

Bass :  +8 dB  -7 dB at 100 Hz

Treble :  +7 dB -6 dB at 10 kHz

Loudness Contour:  +6 dB (at 100 Hz) +3 dB (at 10 kHz)

Filter Low:  15 Hz (6 dB/oct)

Hum and Noise (IHF, short-circuited A network, rated power)

Phono :  76 dB

AUX, Tape Play :  95 dB

FM Tuner Section

Usable Sensitivity: 

Mono : 10,3 dBf (1,8 µV)

50 dB Quieting Sensitivity: 

Mono :  16,2 dBf (3,6 µV)

Stereo :  37,0 dBf (39 µV)

Signal-to-Noise Ratio

Mono :  80 dB

Stereo :  72 dB

Distortion (at 65 dBf)

Mono :  0,07% (at 100 Hz ); 0,07% (at 1 kHz); 0,12% (at 6 kHz)

Stereo :  0,15% (at 100 Hz); 0,15% (at 1 kHz ); 0,25% (at 6 kHz)

Frequency Response:  30 to 15,000 Hz +0,2 dB -0,8 dB

Capture Ratio:  1,0 dB

Alternate Channel Selectivity:  75 dB

Spurious Response Ratio:  65 dB

Image Response Ratio:  65 dB

IF Response Ratio:  90 dB

AM Suppression Ratio:  50 dB

Muting Threshold:  19,2 dBf (5 µV)

Stereo Separation:  45 dB (1 kHz); 35 dB (30 Hz -15 kHz)

Subcarrier Production Ratio:  55 dB

SCA Rejection Ratio:  65 dB

Antenna Input:  300   (balanced); 75   (unbalanced)

AM Tuner Section

Sensitivity:  300 µV/m (IHF, ferrite antenna); 15 µV (IHF, ext. Antenna)

Selectivity:  26 dB

Signal-to-Noise Ratio:  50 dB

Image Response Ratio:  40 dB

IF Response Ratio:  40 Hz

Antenna:  Built-in ferrite loop stick antenna

Semiconductors:  5 FETs; 9 ICs; 37 Transistors; 37 Diodes

Power Requirements:  110/120/220/240 V 50/60 Hz

Power Consumption:  190 W (UL), 340 VA (CSA)

Dimensions (W x H x D):  480 x 140 x 320 mm (18-7/8" x 5-1/2" x 12-5/8")

Weight:  12,2 kg (26 lb 14 oz)


 

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