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There
are two Quad pre-amplifiers, the 34 and 44 which share many features
in common, and differ only in the extent of facilities offered. They
represent the result of more than thirty years experience in the
design and use of pre-amplifiers. The refinements in circuit design
and ergonomics enables the listener to obtain maximum musical
enjoyment from the widest possible range of programme material.
The
pre-amplifier selects the desired programme input, providing optimum
matching for the programme source, amplifies the signal up to
amplifier level and permits the listener to adjust and apply tonal correction.
The
Quad 34 and 44 are normally used in conjunction with one or other of
the Quad power amplifiers, but can also be used with power amplifiers
of other makes.
Optimum
performance from disc depends upon accurate RIAA de-emphasis and
correct matching of both load and sensitivity. Quad pre-amplifiers
have a range of plug-in modules which provide correct matching for
any pickup cartridge, any output level.
It
is widely believed that music should be reproduced through a system
with a flat frequency response. While this may be "hi-fi' it is
seldom likely to reproduce the closest approach to the original
sound. It is only necessary to play a good recording on first class
equipment in two different rooms to realise just how much variation
there can be.
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While
a small number of records can be found which produce excellent
results in any one room without tonal correction, this is clearly
unsatisfactory if one wishes to choose records on musical rather than
technical merit.
Quad
has developed a system of tone controls and filters which used
intelligently  enable
the listener to achieve optimum results from a wide range of
recorded and broadcast programme material.
The
Quad filters cope with tracing distortion. Even with modern stylus
shapes, the tracing distortion from a gramophone record doubles for
every half octave increase in frequency, rising to as high as 5O% at
high frequencies and modulation levels. The filter characteristics
are carefully tailored to remove the unwanted distortion while
leaving the musical information. More of the music and less of the
"hi-fi'. The tilt and bass controls cope with problems of the
listening room and speaker placement.The tilt  control
operates exactly as its name implies and produces a very gradual
change in balance across the musical spectrum without changing the
overall subjective level. When set for ±1—1 there will be a
gradual fall of 2dB from bass to treble with a maximum rate of change
in the centre of not more than 1/2dB peroctave. This absence of
sudden change means that there will be no 'colouration' added to the sound.
The
sound will remain entirely natural but with a slight added warmth.
Such a setting will be used if the recording and/or the listening
room are slightly analytical or overbright. Conversely, if both the
recordingenvironment and the listening room are rather lush sounding,
the —1+1 (or even —2+2) would be used to restore detail.
 In
using this control the extreme bass and extreme treble should not
unduly influence judgement because they are separately adjustable.
The
bass control serves two purposes. In the lift position it acts as a
smooth progressive boost for use with small loudspeakers of
necessarily limited bass response, and the profile of the bass lift
response provides optimum equalisation. In the step mode the control
acts as a step filter which removes the characteristic 'honk' caused
by the excitation of the room's eigontones when the loudspeakers have
to be placed in or near a corner.
The
difference between the Quad 44 and 34 are confined to the input
facilities offered and choice between them should be governed by the
requirements of the system.
The
Quad 34 has four inputs, for disc, radio tuner, auxiliary and tape.
The disc input is supplied with two modules, one for moving magnet
pickup cartridges and the other for low output moving coil pickup
cartridges. Other modules are available for special requirements. The
Quad 34 represents the solution for a music system with up to four
programme sources.
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