4
SETTING UP YOUR AMPLIFIER – LINE INPUTS
The 912 has six line inputs in total, including the tape monitor. Two of the inputs are
balanced, but they all have the same sensitivity. This means that any of them is equally
suitable for any line-level source (CD player, tuner, analogue or digital recorder, etc).
Because of the very low noise, high headroom and high input impedance of the 912, plus
its relatively high gain when the volume control is at maximum, compatibility problems
with any line-level source, of any type or age, are highly unlikely.
Two problems may very occasionally occur. First, transformer coupling is not forgiving
of source components which have a high level of DC (more than a few millivolts) present
at their outputs. Such components can only be regarded as faulty and should be repaired
at once, but such a faulty may look at first like a fault with the 912. The most obvious
symptom would be a serious lack of bass, due to saturation of the transformer core by the
DC. If you suspect that one or more of your source components is producing a DC offset
at its outputs, have the equipment checked by a qualified technician.
The second possible problem relates to equipment with certain types of ‘pseudo-balanced’
outputs which cannot work properly unless they are connected to a ground referenced
input. Because the 912’s balanced inputs are fully floating, such components when
connected to it will produce little or no sound and a very odd frequency response. Again,
this is not a fault with the 912 and should be rectified at source (or simply use an
unbalancing lead to one of the 912’s unbalanced inputs, if this does not result in hum).
SETTING UP YOUR AMPLIFIER – CABLES
Yoshino does not make or market cables and does not endorse any particular brand. In
fact the 912, in common with all Yoshino amplifiers, will work with any cables we are
aware of. This means that you are completely at liberty to select cables which match
your tastes. However, the following guidelines may be helpful.
Interconnect cables should be low capacitance and well screened. High capacitance
cables can give a slight subjective treble loss with many source components, while
unscreened cables have a greater tendency to pick up interference. Avoid excessively
long cables. If interconnects longer than approx. 1ft (30cm) are being used, it is wise to
twist the right and left channel cables together to minimise the chance of hum pickup.
With screened cables, this will not have any adverse effect on channel separation.
The balanced inputs and outputs of the EAR 912 allow for optimum performance when
connected to suitably equipped partnering components (source components and/or power
amplifiers). The most important advantage of balanced cables over unbalanced is that
over long runs they are much less prone to picking up interference, especially mains hum
and they are less likely to introduce unwanted ground connections between equipment
which can themselves produce hum. However, be aware that many source components
