Line 6 XD-V75 Satellite Radio User Manual


 
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Note: Make sure all powered on Line6 TX units are a minimum of 2 meters away from scanning RX
antennas. This will avoid overload and incorrect scanning function while in this mode.
audio outPut & filteR adjustments
Receiver Output Level Adjustments
The default receiver output from the XD-V75 receiver is +0 dB or unity gain. This allows the wireless
unit to use the same mixer gain levels as the equivalent wired microphone, and connect to the mic-level
input of the mixer. If a boost or attenuation from this level is required, the level may be adjusted, using
the following procedure.
OUTPUT ADJUST:
+0dB (NORM)
Press the SETUP button, and under [SELECT FUNCTION] scroll with the ROTARY ENCODER to
[OUTPUT ADJUST]. Press the
ROTARY ENCODER to select. The bottom line of the display will
show a value ranging from -18dB to +12dB. In default mode it will show [NORMAL (+0 dB)], and will
increment in 1 dB steps through the range, going clockwise to increase the level and counterclockwise
to decrease it.
When the desired level is reached, press the
ROTARY ENCODER to select and return to the main
screen. As you turn the
ROTARY ENCODER and increase or decrease the gain, the level changes will
go into effect immediately.
Typically, you will use the [NORMAL] or unity gain position, and use the trim or gain control and the
channel knob or fader on the mixer to boost or attenuate the signal level. This setting will usually result
in the best overall audio system signal-to-noise ratio. With a mix of wired and wireless microphones,
using the [NORMAL] position will allow you to keep the channel faders and trim controls at similar
positions for similar audible levels. If your mixer just has channel level knobs with no additional trim or
gain control, you might choose to make modest level changes at the receiver.
Note, Raising the receiver’s output level, even to the maximum +12 dB, is not equivalent to a line-level
signal. Use the mic-level setting / input on the mixer or other audio device that is next in the signal
chain.
Boosting the output level at the receiver can give less headroom before clipping its output, adding
distortion on the microphone peaks. You will typically add gain at the receiver only when the user of the
microphone is either speaking too softly or is too distant from the microphone and it is more convenient
to add it there rather than at the mixer level control, or if your receiver’s signal is going to a device that
has no level control and you require more level. Return to [NORMAL] when the situation is corrected.
Attenuating the output level substantially can lower the signal-to-noise ratio, resulting in more noise
and hiss coming through the speakers. You will typically add attenuation at the receiver only when the
receiver output is clipping the mixer or other audio device input and there is no attenuation control
available at the mixer.
Note, The general rule of audio gain staging is to enable as much gain as possible at each stage of the
audio signal, while keeping the level below clipping at the input / program peaks. This process starts
with the microphone element itself, and making sure the user is providing a good signal by not having
the mic too far away or speaking too softly. In this case, the [NORMAL] setting on the XD-V75 receiver
should provide the next gain stage with adequate level with enough headroom to prevent clipping. The
trim or gain control on the mixer is the next stage to adjust level, keeping it below clipping on peaks.
The channel fader follows, and then either the subgroup fader or the main mixer output level to the
amplifier. Obtaining the best level at each stage in the audio chain means you will need less gain at the
amplifier to reach the same output level from the speakers, and will be amplifying less electronic hiss
and noise and more of the desired signal.