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Operation PHONE-AMP G109
THE AMPLIFIERS
The input signals are fed to a transitorized stereo amplifier specially designed
for this purpose.
Its operating range covers DC to 200 kHz (-3dB corner frequency) in order to
ensure optimum linearity within the audible frequency spectrum.
Overall gain is set to +8 dB to enable the unit to drive high-Z headphones at
sufficient volume.
To match different headphone characteristics the overall gain may be altered
with the aid of jumpers.
(see page 26 “Jumper Settings” for details).
SPECIAL FEATURES
Please note:
The following chapters refer to internal settings of the PHONE-AMP G109. To
alter these settings, a TORX screwdriver T10 or a 2,5 mm allen key is required.
The more, you should by all means
PULL THE MAINS CORD !!!
after which all settings can be performed without any hazard.
There's hum...
Among other reasons, hum results from equalising currents caused by ground
loops, e.g. due to the system being connected to separate mains outlets.
This can be avoided by "hard" grounding of the PHONE-AMP G109:
It is achieved by setting the ground lift jumper to the GND position.
See page 26 in the technical appendix.
