User Manual
Radial Engineering Ltd. PZ-DI™ User Guide
USING THE HI-CUT FILTER
Another extra feature that is included on the PZ-DI is a
high frequency lter. This is used to warm up the sound of
the instrument by gently rolling off high frequencies above
3kHz while allowing lower frequencies to pass. The high-cut
(low pass) lter is primarily used on buffered instruments
such as acoustic guitars or violins that have a built-in pre-
amp. Engaging the lter will smooth out the top end and
eliminate the edginess that can be problematic with some
lesser quality preamps.
USING THE 180° POLARITY REVERSE
One of the most challenging aspects to using orchestral
instruments on stage is managing feedback. This is particu-
larly difcult when sharing the stage with electric guitars and
drums. As you increase the level of the acoustic instrument,
sound waves from the PA, monitors, and wall boundaries
combine at certain frequencies to create hot-spots known
as room modes. This can cause feedback. The 180° polarity
reverse comes to the rescue by enabling you to reverse
the electrical phase which in turn can move the room mode
out of the way. Best of all, it eliminates feedback without
resorting to using some form of radical lter.
USING THE GROUND LIFT SWITCH
One of the unique features that is built into the PZ-DI is the power system. This converts 48V phantom power using a
switching supply that increases the signal handling capability while enabling the ground lift switch to be engaged without
disconnecting the 48V phantom power. This means that should you encounter a ground loop, you can lift the ground
without having to resort to an external power supply or battery.
8
-20
-15
-10
-5
+0
+5
+10
20 20k50 100 200 500 1k 2k 5k 10k
Hz
PZ-DI Hi-Cut Filter Response
NORMAL PHASE INVERTED PHASE