Sansui AU 999 Owners Manual

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Congratulations on Joining the thousands of proud. satisfied owners of quality Stereo
components from Sansui.

The AU-999 is the most advanced professional control amplifier ever manufactured by
Sansui. Designed specifically for an ardent audiophile like you, it features the refined dull
black panels common to all AU series professional control amplifiers from Sansui.

The preamplifier section is constructed of carefully selected low-noise PNP silicon tran~
sisters, while the power amplifier section features direct-coupled circuits specially de
veloped with the improvement of tone quality in mind. Together, they permit the AU-999
to deliver a full 180 watts (4Q)in music power output with unprecedentedly good tone
quality.

The AU-999 is lavishly endowed with accessory circuits. These include a Tone Selector
circuit, an improved form of the Triple Tone Control circuit that offers a choice in selec-
ting the critical frequencies of tone control; a Speaker Selector which permits connecting
three sets of speaker systems; a Balance Check Switch which simplifies the job of adjusting
for optimum balance of the right and left channel sound volumes; facilities to connect
two phonographs and two tape decks; and a tape reprint circuit which makes it possible
to copy a recorded tape by utilizing two tape decks. Special provisions have also been
made to permit the amplifier to be built up into an electronic crossover stereo system and
permit comparing such a system with a standard stereo setup.

From the superior performance characteristics to the careful finish of control knobs,
Sansuis tradition of quality is evident. Packed with the most advanced circuits throughout,
the AU-999 comes to you with the full confidence and guarantee of the manufacturer.

It is now up to you to read the contents of this manual carefully before setting out to use
it, so you may operate it correctly and obtain the maximum performance it is capable
of offering for many years to come.

CONTENTS

SWITCHES AND CONTROLS .......................................... 3, 4, 5, 6
OPERATIONS .................................................................. 7, 3
----SPEAKER CONNECTION
-RECORD PLAYING
OPERATIONS ................................................................ 9, 10
-RADIO RECEPTIONS
-MICROPHONES
OPERATIONS ................................................................ 11, 12
--TAPE PLAYBACK
--TAPE RECORDING
ELECTRONIC CROSSOVER SYSTEM .................................. 13, 14
MAINTENANCE .................................................... 15, 16, 17,18
ACCESSORIES ........................................................................... 18
SPECIFICATIONS .............................................................. 19
CHARACTERISTICS .......................................................... 20
TROUBLESHOOTING CHART .......................................... 21, 22
CUSTOM MOUNTING ...................................................... 23, 24
DISASSEMBLY PROCEDURE ................................................ 25
BLOCK DIAGRAM/LEVEL DIAGRAM ...................................... 26
ALIGNMENT ................................................................ 27, 28
--TEST POINTS
-MAIN AMP. SECTION OUTPUT BALANCE/CURRENT ADJUSTMENT
PRINTED CIRCUIT BOARDS AND PARTS LIST ...... 29, 30, 31, 32, 33, 34
OTHER PARTS .............................................................. 35, 36

OTHER PARTS AND THEIR POSITION ON CHASSIS .............. 37, 38

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ElEBTRflNlC CROSSBVER SYSTEM

Electronic Crossover System

The electronic crossover system is said to be the
best hi-fi sound reproduction method available,
featuring the following advantages:

1. Since the tweeters, midranges and woofers have
their own amplifier, any speakers of different im-
pedance and efficiency can be used for stereo ar-
rangement.

2. This system has better filter characteristics than
the conventional LC crossover network. You can
determine the Optimum crossover points for the
speakers used.

3. Since there is no component between the ampli-
fier and speaker, the damping factor of the amplifier
is not affected and it is directly coupled to the
speaker.

4. This System allows use of the power amplifiers
effectively and efficiently. For instance, a big-power
amplifier can be used for woofers, and ones with
good characteristics for midranges and tweeters.
You can select the amplifiers suitable for each of
the woofers, midrangas and tweeters.

The AU-999s preamp and main amplifier sections
can be used separately by simply removing a pair
of connectors from the PRE OUTPUT and MAIN
INPUT jacks on the rear panel. This feature en-
ables you to use the Ali-999 as a component of an
Electronic Crossover System in the following man-
ner:

1. Set the SPEAKERS switch to SYSTEM C.

2. Remove the two connectors from the PRE OUT-
PUT and MAIN INPUT jacks.

3. Connect an electronic crossover unit (Sansui
CD-S) to the PRE OUTPUT jacks.

4. Connect the low-frequency output of the electro-
nic crossover unit to the MAIN INPUT jacks on the
AU-999.

5. Connect the right and left woofers to the SYS-
TEM C terminals on the AU-999.

6. Connect the mid-frequency output of the elec-
tronic crossover unit to the inputs of the second
separate power amplifier (Sansui BA-90), and the
right and left midrange speakers to the said power

amplifier.

7. Connect the high-frequency output of the elec-
tronic crossover unit to the inputs of the third sepa-
rate power amplifier (Sansui BA-90), and the right
and left tweeters to the said power amplifier.
Notes:

1. You can connect speakers to the SYSTEM A
and B terminals in addition to the SYSTEM C
and directly compare the sound of the Electronic
Crossover System with that of the ordinary stereo
arrangement by turning the SPEAKERS switch
between the SYSTEM A, B and C positions.

2. The connection of an additional pre-amplifier to
the MAIN INPUT jacks Cuts off all front panel
switches and controls except the BALANCE
CHECK and SPEAKERS switches. Thus, to adjust
the tone and volume, Operate the controls of the
additional pre-amplifier connected to the ALI-999.
When an additional power amplifier is connected to
the PRE OUTPUT jacks, the tone and volume can
be adjusted by the controls of the All-999.

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CUSTOM MOUNTING

How to Install the Amplifier in a Wooden Cabinet

1. As illustrated right, make a cabinet window of 450mm or 1733/32 in
width and 145mm or Ss/g. in height.

2. Place two square pieces of wood (20 X 20 x Z70mm or /3, x lag x 10-
%) for supporting the amplifier in the bottom board of the cabinet.

3. Cut two holes for attachment bolts in the bottom board of the cabinet.
4. Remove the four rubber feet from the amplifier.

5. Place the amplifier in position through the cabinet window.

6. Make sure the amplifier is in position, then put the washers in butterfly
bolts (supplied) and fix the amplifier to the cabinet with butterfly bolts.
Note:

When the amplifier is built into the cabinet. the four rubber feet are not
used. Retain them for future use.

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