Mono Input Channel 1
Front Panel Features
Mono Input channel features are identical for both the X 18R and the X 20R.The X 18R has 14 Mono inputs and the X 20R has 12 Mono inputs.
Line Input (Mic Pad)
With this switch in the UP position, the input preamp circuit is set up to accept a mic-level signal. This signal is brought in via the XLR mic-input connector located on the rear panel.The 1/4" TRS input jack is ignored.
When the switch is depressed, a Pad is inserted into the signal path and the input preamp circuit is set up to accept a line-level signal from either the XLR mic-input connector or the 1/4" TRS input jack, both located on the rear panel.The XLR signal is normaled to the 1/4” TRS jack. If nothing is plugged into the TRS jack, the XLR sig- nal is fed to the preamp when the LINE switch is pressed. Since the TRS signal is always padded down by 26 dB, this feature allows the LINE switch to act as a PAD switch for bringing very hot microphone signals down to a controllable level, avoid- ing overload.When a plug is inserted into the 1/4" TRS input jack, the XLR mic-input signal is disconnected and the signal present on the 1/4” plug is fed to the preamp. If plugs are inserted into both the XLR and TRS jacks, this switch acts as an input selector switch between the two jacks.
Gain
The Input Gain control is used to establish proper gain structure in the channel. For best results, use the Solo system to monitor the channel while you set the gain.The goal is maximum gain without distortion. Both the main LED meters (during Solo) and the channel’s Level/Peak indicator can be used for adjusting gain.
70 Hz Lo-Cut Filter
This filter reduces or eliminates unwanted low frequencies without substantially affecting the program material. Quite often, such unwanted low frequencies are included with mic- or line-input signals. For example, stage rumble or wind can be picked up through vocal mics.The cut-off frequency of the filter is 70 Hz and the slope is -18 dB per octave.This type of filter is also referred to as a Hi-pass filter (HPF). It allows the high-frequencies to pass, but stops the low-frequencies.
Lo Cut Switch
Lo-Cut filter is bypassed.
Lo-Cut filter is on.