Sansui AU 20000 Brochure

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Sansuis AUITU Series of stereo in-
tegrated amplifiers and stereo FM/AM
tuners has received the highest praise,
and has gathered the most devoted fol-
lowing of audiophiles, of any series of
high fidelity components we have ever
manufactured. Since its introduction
more than a decade ago, the series has
always represented not only the latest
and most advanced technical develop-
ments and applications in the industry
but also the finest in user-oriented con-
veniences and design innovations.

In this brochure we are proud to in-
troduce the latest in the Sansui AU/TU
Series. They are the most powerful,
most accurate, most dependable stereo
components yet to join the series, and
they represent at the very highest pro-
fessional level the famed Sansui tonal
quality standards in every respect.

A020000

INTEGRATED STEREO
AMPLIFIER

HIGH-OUTPUT, LOW-DISTORTION
CIRCUITRY

The AU-ZOOOO is the most powerful
integrated amplifier in Sansui's dis-
tinguished AU Series. Its constant and
reliable power output is a cotinuous 170
watts, min. RMS, per channel, both
channels driven into 8 ohms, over a 20
Hz to 20kHz bandwidth with no more
than 0.05% total harmonic distortion.

POWERFUL TRIPLE PUSH-PULL
OUTPUT CIRCUIT DESIGN

No less than six hand-selected power
transistors are used in each output chan-
nel. The triple push-pull circuitry here is
guaranteed to deliver its rated output at
the lowest possible distortion» power to
spare, always.

DEPENDABLE POWER SUPPLY
Particularly close attention is paid
to the power supply design to ensure de-
pendability and stability. The circuit is
the plus-minus symmetrical voltage type,
coupling a low-magnetic-Ieakage toroidal
transformer with extra large capacitors.

DUAL-AMPLIFIER PHONO EQUALIZER
WITH LOW-NOISE TRANSISTORS

Dynamic response is improved by
the 8-transistor equalizer with differ-
ential amplifiers at its initial stages. Dis-
tortion is totally minimized, and the dual
amplifier design-a CR type for highs and
a NF type for lows-achieves very ac-
curate RIAA equalization.

TRIPLE TONE CONTROLS

The AU-20000 features Sansui's ex-
clusive Triple Tone Control design, con-
trolled by a CR type circuit. A wide dy-
namic range and excellent transient re-
sponse are assured by the use of a plus-

minus voltage supply.

COMPLETE TRIPLE PROTECTION
CIRCUITS

Damage and breakdowns are avoid-
ed entirely with the use of a temperature
sensing circuit, a DC voltage detection
circuit and an ASO (Area of Safety Oper-
ation) detection circuit. Shorts in speak-
er terminals or leads, or power/tempera-
ture emergencies instantly activate these
circuits for complete protection.

SELECTABLE PHONO SENSITIVITY/
IMPEDANCE

The phono input circuitry in the AU-
20000 incorporates two special selec-
tors, each with three positions, to allow
the selection of the correct sensitivity
and impedance to obtain optimum results
with any cartridge in use.

VERSATILE TAPE MONITOR CIRCUIT

The AU-20000 accepts up to thl .
stereo tape decks and provides individual
monitoring and deck-to-deck dubbing for
each. It also permits source monitoring
during the dubbing process.

OTHER USER-ORIENTED FEATURES

Provided are: Tone Defeat Switch;
3-Step Audio Muting Swich; 2-Step Low/
High Filters; Mode Switch; Meter Sensi-
tivity Switch, and Large, Self-Illuminated
Level Meters.

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INTEGRATED STEREO
AMPLIFIER

DEPENDABLE HIGH-POWER OUTPUT

The output stage of the AU-11000
features a parallel push-pull circuit de-
sign to ensure reliable high-power perfor-
mance with very low distortion. The
output is a continuous 110 watts, min.
RMS, per channel, both channels driven
into 8 ohms, over a 20Hz to 20kHz
bandwidth with no more than 0.08%
total harmonic distortion. This means
you enjoy the fullest dynamic range pos-
sible for accurate and faithful reproduc-
tion of all sound sources.

POWER SOURCE STABILIZATION
The plus-minus voltage power supply
in the AU-11000 provides constant sta-
bilization. The circuit combines a toroidal
1sformer having very low magnetic
'ilux leakage and a high efficiency with
extra large capacitors.

IMPROVED PHASE CHARACTERIS-
TICS IN PHONO EQUALIZER

Adifferential amplifier is used in the
first stage of the dual-amplifier phono
equalizer. The equalizer amplifier for
the highs is of the CR type and the other
for the lows is the NF type to obtain very
accurate equalization with low distor-
tion.

SANSUI-EXCLUSIVE TRIPLE TONE
CONTROL

An NF type circuit with 12 transistors
is found in the control section of this
sensitive and accurate tone control
stage. Its initial stage uses a differential
amplifier. The popular Sansui-exclusive
Triple Tone Control offers precise tonal
adjustment in three ranges, BASS, MID-
RANGE and TREBLE, and separately
adjustable switches are provided to se~

II IIIV'II'I San-u"

lect the turnover frequency for BASS
(600Hz, 300Hz or 150Hz) and TREBLE
(8kHz, 4kHz or 2kHz). A Tone Defeat
Switch is also provided.

QUADRUPLE PROTECTION CIRCUITS

Shorts in speaker leads, temperature
changes or fluctuations in AC line supply
pose no danger to the AU-11000 or
connected speakers, thanks to the use
of a four-part protection circuit. This
includes(1) a temperature sensing cir-
cuit, (2) a DC voltage detection circuit,
(3) an ASO (Area of Safety Operation)
detection circuit, and (4) an overload
detection circuit.

SELECTABLE PHONO SENSITIVITY/
IMPEDANCE

Phono input circuits can be adjusted
to accept and provide optimum perform-
ance results from virtually any phono
cartridge you choose. The phono circuit
has two 3-position selector switches, one
for impedance and the other for sensi-
tivity.
TWO-STEPPED LOW/HIGH FILTERS

The Low Filter has selectable posi-
tions for 12dB/oct at 20Hz or 60Hz; the
High Filter has selectable positions for
6dB/oct. at 7kHz and 12dB/oct. at
12kHz.

OTHER CONVENIENT FEATURES

The AU-l 1000 provides input/output
facilities for up to two stereo tape decks,
with full monitoring and deck-to-deck
dubbing. Also featured is a quick-access
Tuner Selector, a Mode Switch, a Level
Selector (with positions 0dB/~ 10dB/
-20dB) and an Audio Muting Switch.

INTEGRATED STEREO
AMPLIFIER

PARALLEL PUSH-PULL POWER
OUTPUT SECTION

The power amplifier section of this
robust stereo component features a dif-
ferential amplifier and a 3-stage Darling-
ton system designed in the parallel push-
pull format. The results include a con-
tinuous power output of 80 watts, min.
RMS, per channel, both channels driven
into 8 ohms, over a 20Hz to 20kHz
bandwidth with no more than 0.08%
total harmonic distortion.

STABILIZED, WELL-REGULATED
POWER SOURCE

The power supply section is one of
the most stable and dependable ever de-
veloped, providing plus-minus symmet-
rical voltages to all circuits as needed.
Oversized power capacitors help provide
extra stability, while the use of an ad-
vanced toroidal transformer further as-
sures better power regulation and excep-
tionally low induced hum.

EXCELLENT RIAA EQUALIZATION

The phono equalizer consists of two
amplifying sections each with a differen-
tial amplifier. High frequency roll-off is
made by the CR type circuit and low
frequency turn-over is made by the NF
type circuit, most accurately and with
very low distortion.

EFFECTIVE TRIPLE TONE CONTROL
Sansui's popular Triple Tone Control
circuit is featured in the AU-9900 to
provide the best, most flexible tonal ad-
justment control yet deveIOped. Twelve
transistors are used in the circuit, itself
built around an initial stage using a dif-
ferential amplifier. The individual con-
trols for BASS, MIDRANGE and TREBLE

are made still more convenient by the
selectable turnover switches for BASS
(600Hz, 300Hz or 150Hz) and TREBLE
(8kHz, 4kHz or 2kHz).

QUADRUPLE PROTECTION CIRCUITS

Changes in temperature, line voltage
supply or shorts in speaker leads or ter-
minals are instantly detected and can
cause no damage to the power transis-
tors or connected speakers thanks to the
use of four separate protection circuits.
These are: (1) a temperature sensing
circuit, (2) a DC voltage detection circuit,
(3) an ASO (Area of Safety Operation)
circuit, and (4) an overload detection
circuit.

TONE DEFEAT SWITCH

Like the AU-20000 and AU-11000,
this integrated amplifier provides the
convenience of being able to cancel all
tone control adjustments instantly with
3 Tone Defeat Switch.

TWO-STEPPED LOW/HIGH FILTERS

The Low Filter has positions for 12
dB/oct. attenuation at 20Hz or 60Hz;
the High Filter is selectable for 6dB/oct
cutoff at 7kHz or 12dB/oct. cutoff at 12
kHz.

OTHER VALUABLE FEATURES

The AU-9900 provides every con-
venience needed for professional and
semi-professional use. Included are a
hand-trimmed precision volume control,
input/output terminals for up to two
stereo decks, with full monitoring and
deck-to-deck dubbing, a quick-access
Tuner Switch, Mode Switch, Level Selec-
tor (0dB/-10dB/-20dB) and an Audio
Muting Switch.

TIIIIIIIIII

FM/AM STEREO TUNER

DEPENDABLE PLUS-MINUS POWER
SUPPLY

Musical reproduction from broadcast
sources depends heavily on correct and
accurate power supply circuitry. The
TU-9900 ~-finest of the Sansui TU Series
-incorporates an elaborate feedback
type stabilized power supply section for
this very reason. It is of the plus-minus
dual supply type to guarantee ideal cir-
cuit performance at all times.

SUPERLOW DISTORTION, 0.06%

A wide-band ratio detector and a PLL
(Phase-Locked L00p) circuit in the FM
multiplex demodulator are employed for
lower phase deviation. The TU-9900
thus boasts a very low distortion figure
of 0.06% (mono) and 0.08% (stereo) in
FM operation to bring its performance
up to the quality required by the very
best amplifier components.

SELECTABLE FM IF BANDWIDTH

To enhance both the tonal quality
and the reception ability of the TU-9900,
Sansui has provided a switch to select
either a WIDE or NARROW FM IF band-
width. In the former, two 6-pole LC block
filters are put on line to improve the
sound quality; in the latter, a narrow-
band ceramic filter is added for more ef-
fective rejection of adjacent signals.

AUTOMATIC NOISE CANCELLER

When receiving weak (or remote) sta-
tions, this circuit automatically blends
the left and right signals in optimum
proportion to the strength of an incom-
ing broadcast to deliver the same noise-
free reception of any station regardless
of its strength.

HIGH-PERFORMANCE FM FRONTEND
The TU-9900 features a sensitivity

of 1.5,.N (IHF) thanks to its linear-fre-
quency 5-gang variable capacitor and
the three dual-gated MOS FETs and a
transistor employed in the high-perform
ance FM frontend.

QUALITY AM RECEPTION

AM broadcasts are received cleanly
and quietly with the lowest noise or inter-
ference possible thanks to the use of a
double-tuned circuit and a dual-element,
dual-coil ceramic filter in the AM section.

POSITIVE ACTION TUNING

The feel and accuracy of the special
tuning mechanism in the TU-9900 will
be appreciated for years of hard and fre-
quent use. It features an oversized

tuning knob a special tension mecha-
nism, and a heavyweight, high-inertia
sintered iron flywheel.

SPECIAL FEATURES FOR TAPE
RECORDING

Tape buffs will
three special features:

(1)A built-in recording test signal
generator is provided to facilitate pre-
recording calibration of Optimum record-
ing levels.

(2) A |ow~pass filter is included to
prevent the carrier frequencies of FM
broadcasts from interacting with the bias
frequencies of decks in use, thus avoid-
ing the annoying beat noise otherwise
heard. The filter can be defeated by a
front panel switch when not recording.

OTHER IMPORTANT FEATURES

The TU-9900 has an FM Antenna
Attenuator Switch to cut down the
strength of excessive incoming signals,
a Multi-Path Detection circuit to help
align antennas, highly accurate Twin
Tuning Meters, FM MUTING SWITCH,
DOLBY FM output terminals, and an Out-
put Level Control.

appreciate these