Sound Performance Lab Area 5.1 - Manual (Page 7)

7
Operation
Preamplifier
Ch. 1-4 Lock
To activate the master mic gain control, press the Ch.1-4 lock
button in the channel 5 section. Now the mic gain control of
channel 5 is the master control for all five channels. The mic gain
controls allow amplfications from 24 dB up to 60 dB.
Pad
The Pad switch (long life gold plated relais) attenuates the input
signal by -25 dB, allowing high-level signals to be preamplified.
This may apply to loud drum or brass recordings. Line-level
signals (like keyboards or other preamplified signals) may be
processed as well.
Rev
The phase reverse switch (long life gold plated relais) reverses the
polarity of the microphone signal. If the switch is pressed the
phase is rotated through 180º. Incorrect polarity leads to an unna-
tural tone and to drastic tonal changes, if the distance to the
microphone is varied. We recommend that you check the polarity
and correct it if necessary before commencing recording.
48 V
The 48 V phantom power button serves to supply condenser
microphones which are equipped with in-built preamplifiers. A
precise construction and disturbance free electrical supply are
the main requirements for their trouble free operation. The vol-
tage is maintained precisely at 48 V and delivers a maximum
current of 14 mA, sufficient for all types of microphones.
WARNING: All microphones with balanced, ground free output
(including tube microphones) can be operated with phantom
power switched on. The following procedure is to be adhered to:
Firstly connect the microphones to the Area 5.1, then switch on
the phantom power – you can now commence work. When recor-
ding has been completed firstly switch off the phantom power
then wait 30 seconds before disconnecting the microphone from
the Area 5.1. This allows residual voltages to be discharged and
improves operational safety. Phantom powering is only used
with condenser microphones. With any other type of micro-
phone it is to be switched off! An unbalanced microphone is
not to be used with phantom power switched on!
Sub/LFE channel
In the Sub/LFE channel the Sub signal can be composited from
any combination of L/R, C or SL/SR inputs. The gain control allows
to adjust the Sub/LFE channel output level between -26 dB and
+6 dB.
Operation
Sub/LFE channel
Area 5.1