Owner`s manual

ADDITIONAL INFORMATION
Running In
Most high fidelity equipment works better after it has been run in for some
time. In the case of valve amplifiers the period of running in is much more
important. Components that go into valve equipment work at voltages and
temperatures far higher than their solid-state counterparts and when new
they should spend an extended period at those working temperatures to
bed in properly. This is especially the case with the output valves and the
output transformer.
We recommend an initial running in period of at least four and preferably
twelve hours before you first use the equipment. If you decide to run in
your equipment for an extended period, make doubly sure that all the
safety conditions covered in this manual are fully met. Supervise the
equipment for the first hour or so and if you have to leave the equipment
unattended thereafter, have someone to look in every so often to make
sure all is well.
The patience and care that you devote in these initial stages will be amply
rewarded by many years of outstanding performance from your QUAD
valve equipment.
Valve lifetimes
Valves contain a heating element. This heats up the valve's cathode, which
is specially coated to give off a steady stream of electrons. This coating
will eventually become exhausted and the valve's performance will
deteriorate. In the QUAD II – forty power amplifier the KT88 output
valves are most likely to deteriorate first but the 6SH7driver valves will
also eventually wear out. As the valves start to wear out the sound will
become softer and less well defined and a lack of dynamics and power
will become evident.
The KT88s should last over 6,000 hours and the 6SH7s 15,000 hours of
listening but a longer life can be expected. The 6111WA used in the QC -
twenty four is a military type with a lifetime of 60,000 to 100,000 hours so
it should not need to be replaced for a long time into the future.
When replacing valves it is essential to use the highest quality available.
Poorly manufactured KT88s will adversely affect the sound quality and
may damage the amplifier. Before the amplifiers leave the factory they
are fitted with balanced sets of valves to ensure optimum performance.
These tests are performed with sophisticated analysis equipment so, to
ensure that your amplifiers always perform as they were intended, please
return them to an authorised QUAD Service Department for servicing.
Output Transformer
The output transformer is the most expensive component in a valve power
amplifier. It is designed to match the high voltage, low current conditions
in which output valves operate to the low voltage high current
requirements of a loudspeaker. Although robust and capable of lasting a
lifetime, an output transformer can be damaged and, in extreme cases
wrecked, by careless use.
If you operate a solid-state amplifier into a short circuit something
dramatic is likely to happen fairly quickly. If you play a valve amplifier
into a short circuit, the output transformer will soak up a lot of energy
before failing but if the short persists the transformer could be damaged
catastrophically.
Paradoxically, operating a valve amplifier at high output levels with no
loudspeaker connected can damage an output transformer. The analogy
here is to an engine racing away with no load - sooner or later it will burn
out.
IMPORTANT NOTES
European Union Directives:
QUAD equipment is designed to comply with the legal provisions of EU
Directives 89/336/EC and 72/23/EEC. The standards that have been
applied were those in force at the time of the introduction of the product.
The product bears the CE mark
Compliance cannot guarantee perfect performance. In the very rare
circumstance that you experience problems you should first try to locate
and remedy the origin of any disturbance. A further option is to relocate
the QUAD equipment in order to reduce the interference. Your dealer
should be able to provide assistance if the problem persists.
FCC Rule 15 Class B:
This equipment has been tested and complies with the limits for a Class B
device, pursuant to Part 15 of the FCC Rules. These limits are designed to
provide reasonable protection against harmful interference in a residential
installation. This equipment generates, uses and can radiate radio
frequency energy and, if not installed and used in accordance with the
instructions, may cause harmful interference to radio communications.
However, there is no guarantee that interference will not occur in a
particular installation. If this equipment does cause interference to radio or
television reception, which can be determined by turning the equipment
off and on, the user is encouraged to try to correct the interference by one
or more of the following measures:
Reorient or relocate the receiving antenna.
Increase the separation between the equipment and the receiver.
Connect the equipment into an outlet on a mains circuit different to
that to which the receiver is attached.
Consult the dealer or an experienced Radio/TV technician for help.
Information to the user:
Alteration or modifications carried out without appropriate authorisation
may invalidate the user's warranty.
It is always good practice to switch off equipment before connecting or
disconnecting signal leads. This will prevent unpleasant and loud noises
coming from the loudspeakers and avoid the risk of damage to equipment.
It is important that any unit connected to this equipment is earthed
according to the manufacturer's instructions. This becomes more
important as the number of units that are connected together increases.
Noise Pollution:
Please be aware that very high sound pressure levels can cause permanent
damage to your hearing and also severe annoyance to neighbours.
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