Switchable pre-attenuation 
The gain can be reduced by 12 dB. This is recommended when the subsequent micro-phone input is overmodulated or when the MZA 900 P’s output is strongly biassed by the subsequent device, e.g. due to high sound pressure levels from drums, brass instruments, etc.
Please note that when operating the MZA 900 P on 12V phantom powering, its output is considerably biassed by the power supply. If this is the case, and when high sound pressure levels occur, the pre-attenuation should also be switched on.
Switchable roll-off filter 
The roll-off filter allows the MZA 900 P to be adapted to Sennheiser HSP and clip-on microphones. With the roll-off filter switched on , the low-frequency signal portions (below 125 Hz) are attenuated, thus increasing speech intelligibility. In addition, pop and wind noise is effectively suppressed.
Using the MZA 900 P as a cable tester 
The MZA 900 P can also be used as a cable tester for XLR microphone cables. For this, there is no need to connect a microphone.
Connect one end of the cable to be tested to a mixing console with activated phantom powering. Connect the other end of the cable to the MZA 900 P.
LED lights up in green
The cable is OK
LED lights up in red
Possible errors:
One signal wire is broken
One signal wire is short-circuited to the shielding
LED does not light up
Possible errors:
Both signal wires are broken
The shielding is interrupted
Both signal wires are short-circuited to the shielding