Glyph GPM-216 - Manual (Page 13)

Glyph GPM-216
13
Many mics need phantom power applied. Phantom power can be applied from two places at the same time,
and everything should still work smoothly. The preamp with the higher phantom power output will end up
powering the mic, while the other will not add any more voltage to the wire.
A similar situation holds true when two microphone preamps are pre-amplifying a microphone signal. The
microphone signal is not ganged and there will be no audio degradation in the signal.
About Direct Outputs (D.I.) and Direct Boxes
It is important to point out that the GPM-216 does not have direct outputs included, and it will often be
necessary to use a direct box after the GPM-216.
A direct box is an electronic device utilizing a transformer or amplifier to change the electrical output of
an electric instrument (for example, an electric guitar) to the impedance and level usually obtained from a
microphone. The function of a direct box can also be built into another piece of gear and is sometimes
called a direct out.
If you plan on plugging an instrument (for example, an electric guitar) into one of the front panel universal
inputs, you would still need to patch a ¼” cable from the rear panel TRS Thru connector to a direct box.
The direct box would change the impedance from instrument to microphone level, which would allow you
to connect to the stage snake. You could not use the rear panel XLR Thru connector as a direct output.
Auxiliary Send/Return 1 and 2
The auxiliary send/return jacks are two ¼” TRS jacks on the back panel of the GPM-216. The tip is send,
the ring is return, and the sleeve is ground. The aux jacks act as per channel inserts for the two local A and
B inputs. The purpose is to provide an insert point for local processing units such as reverb, EQ and
dynamics into the musician's signal flow. These jacks are directly wired to the inputs on the GPM-216 so
that the musician can affect his own input signal in his monitor only. The affected signal is not broadcast to
other GPM-216s on the network, it can only be heard on that musician’s unit. You can use the input gain
control on the external processing unit to adjust the input level if the output from the GPM is too high or
too low. The return signal level will be determined by the output level control on the external processing
unit.
NOTE: The GPM-216 has built-in reverb for the local inputs. If the GPM’s internal reverb is applied to local
signals, they will be broadcast to the network with reverb.
Left and Right Main Insert
Similar to the aux jacks, the GPM-216 has Main Inserts that appear on the back panel. The Main Inserts are
used for adding local processing such as reverb, EQ and dynamics to the entire mix prior to being sent to
the Left and Right Main Outputs. Again, the effects are only heard on that musician’s unit and are not
broadcast to other units over the network. You can use the input gain control on the external processing
unit to adjust the input level if the output from the GPM is too high or too low. The return signal level will
be determined by the output level control on the external processing unit.
USB Port
The USB port is supplied for future functionality.