Lake People G109P Bedienungsanleitung Seite 23

Operation PHONE-AMP G109
By this measure, the internal reference ground is directly connected to the case
/ earth potential. Whereas LIFT means that the unit becomes insensitive to low-
frequency inter-ference. High-frequency interference however is still bled off to
ground or case respectively.
In all cases full electrical safety is maintained, since the case is permanently
grounded via the 3-pin mains plug !!
Too loud ? Too soft ? ... the PRE-GAIN concept
The G109 is specially designed to drive headphones. However, these can
present loads between 8 ... 2000 ohms and efficiency factors between
85 ... 115 dB/mW. This makes it a little bit difficult to fulfil all desires, because ...
... owners of high-efficiency headphones may rarely turn the volume control
over the nine-o'clock position without risking hearing damage, while even
the max setting may be too soft for low-efficiency headphones ...
... all users expect maximum quality at lowest noise and distortion ...
Therefore the circuitry must be able to adapt to these conditions, since
headphones won´t !
PRE-GAIN
THAT'S WHAT WE CALL
The adjustment is made in the preamp section, where the signal can be boosted
or attenuated in three steps.
See page 26 in technical appendix.
In case you find that the G109 could well be somewhat softer - e.g. in order to
widen the setting range of the volume control - set the corresponding jumper to
the -12dB position.
23