BSS Audio
MSR-604ii User Manual version v1.4
Page 10
5 MSR-604ii Controls
Phantom On/off
The MSR-602ii power supply provides each MSR-604ii with 48v DC for phantom
powering capacitor microphones. This is selected by operating the individual
channel switch and it is connected across the ‘input’ connector in the standard
phantom powering manner. Typical current availability is 10mA per channel for a
40 channel system.
Phantom power is indicated by a front panel LED.
It should be noted that phantom powering is interlocked to the LINE/MIC switch so
that when LINE input is selected phantom power and the LED indicator are
disabled.
Line/Mic
This switch introduces a 20dB pad into the input circuit of the unit, and raises the
input impedance to suit line level signals. In the mic position the maximum signal
level is +13dBu (with the GAIN set to -10dB). In the line position phantom
powering is disabled and the maximum permitted signal level is +33dBu (with the
GAIN set to -10dB).
Gain
The GAIN switch allows the input amplifier gain to be changed in 10dB steps from
-10dB to +30dB to precisely match the input signal to the internal headroom of the
MSR-604ii. Combined with the very low inherent noise of the input stage this
ensures that none of the dynamic range of the source is lost.
The absolute system gain is dependent upon the internal system configurations
chosen, but with factory default settings and in the MIC position the gain indicated
on the GAIN switch setting is correct, i.e. with a mic input, 0dB gain selected and
default jumper settings the output level is the same as the input signal.
Clip LED
The CLIP LED which is situated below the GAIN switch illuminates when the peak
signal level approaches within 1dB of clip. It features a fast acting full wave
rectifier and a hold circuit which ensure that all transient peaks are unambiguously
indicated.
Remote attenuator
A 10dB input pad is activated when the channel detects a +48v phantom signal is
present on the MAIN OUTPUT. This allows the front of house mixing engineer to
remotely reduce the input signal if he detects that the channel is being overdriven.
This is a not uncommon occurrence in live rock and roll, when musicians get into
the spirit of a performance and sing louder than during sound checks.
A front panel LED indicates when REMOTE ATTENUATOR is active.
