Quad 306 Owners Manual

Page 1

306

POWER AMPLIFIER

INSTRUCTION BOOK

QUAD

Page 2

CONTENTS

WEC

page

INTRODUCTION ...................................... 2
GUARANTEE ....................................... 2
SERVICE ........................................... 2
ACCESSORIES SUPPLIED ............................. 3
INSTALLATION ...................................... 3
Checking the AC Power Supply .................... 3
Connecting to the AC Power Supply ................ 4

AC Power Out ................................... 4
Positioning the Amplifier .......................... 4
Connection to the Control Unit ..................... 4
Loudspeaker Connection ......................... 5
SWITCHING ON AND OFF .............................. 6
AMPLIFIER PROTECTION .............................. 6
LOUDSPEAKER PROTECTION ......................... 6
QUAD ELECTROSTATIC LOUDSPEAKERS ................ 6
LOUDSPEAKER PHASING ............................. 6
HEADPHONES ....................................... 6
MAINTENANCE ..................................... 6
FRONT AND REAR VIEW .............................. 7
Connecting Sockets ............................. 7
SPECIFICATION ...................................... 8
Power Output Graph ................... inside back cover
ACCESSORIES ............................ Inside back cover

Quad high lldelity equipment ls designed to reproduce music
at realistic levels. but there is a world of diherence between the
sound levels produced by a string quartet and a heavy metal group.

Please be aware that very high sound pressure levels can cause
permanent hearing damage, but such levels would also cause
severe annoyance to neighbours.

past-1

Page 7

SWITCHING ON AND OFF

AMPLIFIER PROTECTION

LOUDSPEAKER PROTECTION

QUAD ELECTROSTATIC
LOUDSPEAKERS

LOUDSPEAKER PHASING

HEADPHONES

MAINTENANCE

mos

Switching On - Press the onloff button. This has a sequential action so
pressing it again will switch the amplifier off. Leave the amplifier switched on.
In normal use it will be controlled via the on/oflswitch on the Quad control unit.

The 306 amplifier is protected by a resettable current trip which interrupts the
incoming AC Power supply it the amplifier is grossly overloaded for a period of
time. To restore operation simply press the red reset button on the back panel.
It is thus fully protected against gross overload. short-circuited output etc. but not
necessarily against seriously inadequate ventilation.

The laudspeaker manufacturer will usually state a maximum recommended
amplifier power output. but as the maximum sale power for most loudspeakers
is time and frequency dependent it is difficult to define precisely for a musical
signal. Some manufacturers will permit their loudspeakers to be used with
amplifiers exceeding the quoted handling provided certain precautions are
observed. This can sometimes be an advantage in enabling short duration
peaks to be handled without overload. The advice of the loudspeaker
manufacturer should always be obtained if in any doubt.

The 306 amplifier is fully compatible with the Quad ESL63 loudspeaker. lt
sh0uld not be used with the earlier model ESL which could be damaged by signal
peaks. A protection circuit is available to prevent Such damage and is fitted
inside each loudspeaker - please contact Quad Electroacoustics Ltd for details.

If there is any doubt about theway the loudspeakers are connected their phasing
can easily be checked by playing a mono source when the sound should appear
to emanate from a point midway between the two loudspeakers. If this is
indefinite then the connections to one of the loudspeakers should be reversed.
When correctly connected the loudspeakers will give a definite centre sound
source with more full bodied tenor and bass registers.

Headphones will normally be used in place of loudspeakers and there are a
number of suitable switch units available designed to enable the loudspeakers
to be switched off when the headphones are plugged in. Most of these
incorporate a simple attenuator circuit to permit operation at normal settings of
the control unit volume control.

Electrostatic or other types of headphones requiring a high level input should be
operated in accordance with the manufacturers instructions.

No routine maintenance is required. If necessary the case can be cleaned with
a soft brush or, for more stubborn marks. a slightly moistened lint-free cloth. in
this case remove the mains plug from the supply socket. Do not use cleaning
agents. solvents or abrasives.

Page 11

Power Output Graph

ACCESSORIES

'Y-MEFGIE IHEMWM

l2 I! I! IS

Quad accessories are designed to match Quad equipment and to provide
the best possible performance. Please contact your dealer or Quad direct

for further information.

Item
Quad rack 34/FM4/306
Quad pedestal
Double sleeve for FM4134 (grey)
19' rack mounting panel for 34/FM4/306 (grey)
Signal lead Phono (0.5m)
Signal lead Phono (1m)
AC interconnect supply lead Euro/Euro (0.45m)
AC interconnect supply lead Euro/Euro (1m)
AC supply lead Euro/tree end (2m)
AC Euro output connector
Speaker plug 4 mm red
Speaker plug 4 mm black

Order No
QRACKC3
OPEDASG
OTUCOVG
M20341 A
QPZPZSA
OP2P21 A
QSPESSB
OSPE81 B
OESOEZA
PPROM 3
PP6091 2
PP60920