Yorkville PGM8 - Manuel (Page 4)

2
Input Channel Features
1. Microphone Inputs
All mono and stereo input channels have microphone XLR inputs. These microphone inputs
are bal anced for maximum noise suppression. The PGM8 active input circuitry accepts micro-
phones with impedances ranging from 50 ohms through 10,000* ohms. All low impedance
microphones are compatible. Phantom power (covered in the Rear Panel section of this man-
ual) is available on all Mic inputs when activated. This feature is for condenser microphones
but you can also connect dynamic microphones without any problems.
*Although it would be customary to plug high impedance microphones into the Line
jacks, most of them will also work in the Mic inputs, provided the microphone’s built-in
XLR connections are wired with the audio signal on pin 2 and pin 3 is connected to pin 1.
2. Balanced Line Inputs
Mono line-level sources, such as guitar amplifier line-level outputs, keyboards, and
hi-impedance microphones, connect to the mono or stereo channels through the line
input jacks. The Left and Right Line inputs on the stereo channels are wired internally
so that a single (mono) signal connected to the L/Mono input will also be patched over
to the Right input (as long as a phone plug is not plugged into the Right jack). This
simplifies connecting a mono source, should the need arise (in the situation where all
the mono channels are taken).
You can connect stereo audio sources such as a digital audio player, CD-player, MP3
player or tape deck to the Line inputs on the stereo channels. Use RCA to phone plug
adapters to connect RCA cables to the Line inputs. It is possible to connect stereo sourc-
es to the mono channels, however you will need to plug the L&R signals into separate
channels to avoid the risk of inter-modulation distortion. The inter-modulation distortion
may be caused by using a “Y” connector to combine the left and right signals into a sin-
gle Line jack. If you connect a stereo source to two mono channels don’t forget to adjust
the Pan controls so that one is set to L and the other is set to R. this will make sure that
the left and right music signals remain separate.
Channel 4 has a very high impedance, unbalanced ¼-inch input which is opti mized
for instruments such as acoustic electric guitars. Push the Hi-Z switch in to change
channel 4 to a high impedance input.
The balanced connector wiring is:
Tip (or XLR pin 2) = hot, in phase;
Ring (or XLR pin 3) = hot, reverse phase;
Sleeve (or XLR pin 1) = ground
You can connect an unbalanced source to the Line inputs with a standard unbalanced
shielded patch cable without any adverse affects.
A slight modification to a balanced patch cable will help achieve noise cancellation
when connecting the PGM8 to an unbalanced unit. Simply modify one end of a bal-
anced patch cord and de-solder the wire from the ring tab, then resolder the wire to the
1/4-inch Phone Plug
1/4-inch T.R.S. Phone Plug
XLR Plug
1
Line
2
Line
3
Line
4
Line Line Line
5/6
Mic Mic Mic Mic Mic Mic
7/8
Hi-Z