Lake People SYM-AMP F12 Bedienungsanleitung Seite 6

GAIN AMPLIFIER
The input signals are fed to active buffer sta-
ges. To suit nearly all possible applications,
their gain can be set individually between -1
and +21 dB. The affilliated trimpots are located
on the front panel and denoted with upward
pointing arrows, "L" / "R" and "A", "B" and "C"
for section assignment.
Section "A" is equipped with an additional RIAA
preamp for direct connection of magnetic car-
tridge turntables.
It is inserted into the signal path by jumpers in-
side the unit. Gain is fixed to 40 dB at 1 kHz.
Further gain control is provided by the section
"A" trimmer on the front panel.
BALANCING STAGE
Depending on the option ordered, signal balan-
cing is provided either electronically or by ba-
lancing transformers.
HINT:
In case of unbalanced termination of the elec-
tronically balanced outputs pin 3 of the XLR
connector may not be shortened but must be
left open!
In case of unbalanced termination signal level is
reduced by 6 dB!
OPTION:
As an option the SYM-AMP may be equipped
with high quality output transformers. These
transformers are controlled by a special circuitry
to achieve low inner resistance, very good fre-
quency range and low distortions. They exceed
IRT recommendations.
OUTPUTS
The balancing stage outputs are fed to XLR ter-
minals on the rear panel.
The polarity of the outputs meets AES 14-1992:
1= ground, 2= in phase (+), 3= out of phase (-)
The output impedance is aprox. 30 ohms.
The outputs are denoted sectionwise as "L" and
"R".
In order to avoid ground loop problems, ground
can be lifted by pulling jumpers on the circuit
board.
THE DIFFERENTIAL AMPLIFIERS
INPUTS
The stereo input signals are injected via XLR
terminals on the rear panel.
The polarity of the inputs meets AES 14-1992:
1= ground, 2= in phase (+), 3= out of phase (-)
The input impedance is aprox. 10 kohms.
They are denoted "L" and "R" and assigned to
the sections.
While the standard version has electronically
balanced inputs, a transformer balanced versi-
on is available as an option.
OPTION:
As an option the SYM-AMP may be equipped
with high quality ZFT (zero-Field)- Transformers
in ist inputs. The technical data of these trans-
formers exceed IRT recommendations.
AMPLIFICATION
The input signals are fed to a differential ampli-
fier for 'unbalancing', followed by an inverting
amplifier stage.
Signal attenuation can be adjusted by front pan-
el trimpots from -21 to +1 dB in order to achieve
optimum level matching for any purpose. The
trimpots are denoted "L" and "R" and assigned
to the sections.
OUTPUTS
The differential amplifiers' output signals are
available via cinch sockets on the rear panel.
These sockets are again denoted "L" and "R",
according to the respective section. Section "B"
and "C" outputs are additionally fed to parallel
outputs on the front panel.
The impedance of the unbalanced outputs is <
50 ohms.
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