Pioneer
SA-5200 - A compact,
value-priced stereo integrated amplifier with advanced solid state circuitry
and top versatility.
In the
medium power and price range, few stereo amplifiers can match Pioneer's SA-5200 for value and versatility. Designed
for the person who is building his first set of home stereo components, this
solid state amplifier offers the very latest circuit technology distinguished
by superior stability and versatility. From the equalizer section to the power
amplifier stages, the SA-5200 offers improved circuit design. The equalizer is
unmatched in this price range for its precise RIAA equalization within +_0,5 dB
as well as its ability for handling large inputs. In the power amplifier
section, Pioneer has chosen complementary SEPP (Single-Ended, Push-Pull) ciruit
with silicon transistors, offering ghigh efficiency and low distortion while
delivering 13 watts + 13 watts of continuous power, both channel driven at 1
kHz into 8 ohms. The outstanding sound character of the SA-5200 makes it a
value and a half, and the extent of this value is more than apparent when you price
this amplifier. Another dynamic difference in true hi-fi components from
Pioneer.
Circuit
Description
Equalizer
Amp
The signal
from the Phono input terminal is fed to the input terminals of the equalizer
amplifier stage, which employs a two-stage direct coupled circuit.
Since
sufficient negative feedback from the second-stage collector is fed to the
first-stage emitter, characteristics accurate to within ±0,5 dB on the RIAA
curve can be provided. Compared with previous two-stage direct coupled
circuits, this system makes for greater stability in the bass range and
provides a surplus dynamic margin.
The
amplified signal from the second-stage collector is fed to switch circuit-A
ass'y through the Function Switch.
Control Amp
The signal
selected by the Function switch is fed to the control amplifier through the
Tape Monitor switch in switch circuit-A ass'y the loudness compensator circuit
in switch circuit-B ass'y, and a potentiometer. The Tone Control circuit
employs the nominal CR type configuration, and is connected after the one-stage
amplifier. As in the bass and Theble tone controls, click-stop volume controls
are employed, which provide high accuracy for flat frequency characteristics at
the middle point of control knobs. The output of the control amplifier is fed
directly to the power amplifier.
Power Amp
The power
amplifier stage consists of seven transistors for each channel. It is composed
of the thruout direct coupled circuit
with differential amplifier.
The signal
from the control amplifier ass'y is fed to one base in the differential
amplifier. The AC and DC negative feedabck from the output junction is fed to
another base in the diffecrential amplifier so that overall stability is
improved.
The
differential amplifier output connects directly with the pre-driver base and
amplifier. The signal from the pre-driver is amplifies by the driver and the
power output stage, and fes to the speaker terminals through the Speaker switch
in switch circuit-A ass'y.
Temperature
compensation in the power amp ass'y is accomplished by a three-element varistor
and the idle current adjustment by a semi-fixed variable resistor connected in
series to the varistor.
Power
transistor protection is accomplished by the fuse installed in series at the
B-power circuit.
Power Supply
A full-wave
rectifier circuits aupply all DC power. The rectified DC, with the ripple
component eliminated by means of a 4,700 µF capacitor, is supplied for the
output circuitry of the power amplifier circuit, and through CR filters for the
other stages. The muting circuit eliminates the unpleasant noise usually heard
when the power switch is turned On or Off. When the power switch is turned ON,
the first-stage transitor Q1 in the power supply circuit is cut off immediately
by the reverse bias caused by a diode
associated with the base.
When the
power switch is turned OFF, the negative bias which has kept the first-stage
transistor cut off is turned over to positive bias, and current entering the
driver-stage transistor makes the second-stage transitor base connect to
ground, the transitor cuts off the bias current entering the driver stage in
the power amplifier ass'y. thus the amplifier stops working and unpleassant
noise is eliminated.
A diode
connected between the base and the emitter of the second-stage transistor
permits discharge of the current charge in the power amplifier ass'y when the
second-stage transistor is cut Off (when the power switch is turend Off).
Specifications
Power
Amplifier Section
Circuitry: 1st Stage Differential Amplifier, Dirct
Coupled Quasi-complementary
Continuous Power Output (both channel driven
at 1 kHz):
15 W +
15 W at 4 Ω
13 W +
13 W at 8 Ω
Continuous
Power Output (each channel driven at 1 kHz):
20 W /
20 W at 4 Ω
16 W /
16 W at 8 Ω
Power Output
in 20-20,000 Hz (both channel driven):
10 W +
10 W at 8 Ω
Total
Harmonic Distortion:
At
continuous Power Output :
less than 0,8%
At 1 W + 1 W
Power Output : less than 0,2%
Intermodulation
Distortion:
At
Continuous Power Output :
less than 0,8%
At 1 W + 1 W
Power Output : less than 0,4%
Power
Bandwidth (both channel driven IHF): 10
Hz - 40 kHz (THD 0,8%)
Output
Speaker: A, B, A+B (4 - 16 Ω)
Output
Headphones: 4 - 16 Ω
Damping
Factor: more than 30 (1khz, 8 Ω)
Preamplifier Section
Circuitry
Equalizer-amplifier: 2-stage Direct Coupled NFB type
Control-amplifier: CR type
Frequency
Response:
Phono (RIAA
equalization): 30 Hz - 15 kHz ±0,5 dB
Tuner, Aux
1, 2; Tape Monitor : 15 Hz - 30 kHz ±1
dB
Hum and
Noise (IHF, Shsort-circuited, A-Network):
Phono : more than 70 dB
Tuner, Aux
1,2; Tape Monitor : more than 90 dB
Input
Sensitivity/Impedance:
Phono
Mag : 2,5 mV/50 k Ω
Phono
Overload Level : 100 mV/280 mV (rms/p-p)
Tape
Monitor: 150 mV / 100 k Ω
Tape Rec/Pb
(DIN connector): 150 mV/100 k Ω
Aux 1,
2 :
150 mV/100 k Ω
Tuner
: 150 mV/100 k Ω
Output
Level/Impedance:
Tape Rec
: 150 mV
Tape Rec/Pb
(DIN connector) 30 mV/80 k Ω
Bass
Control: +12 dB; -10 dB at 100 Hz
Treble
Control: +9,5 dB; -10,5 dB at 10 kHz
Loudness
Contour (-40 dB position): +10 dB at 100
Hz ; +6 dB at 10 kHz
Power
Requirements; AC 120 V 60 Hz or AC 110 V
, 120 V, 130 V, 220 V and 240 V 50/60 Hz (switchable)
Power
Consumption: 85 W max
AC
Outlets: 1 Switched, 1 Unswitched
Semiconductors: 22 Transitors; 7 Diodes
Dimensions
(W x H x D): 415 x 132 x 328 mm
(16-5/16" x 5-3/16" x 12-15/16")
Weight: 7,2 kg (15 lb 13 oz)
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