Sirus Live M416, Руководство пользователя

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channel fader becomes the source master to all monitors. In this case start with all channel faders set
to ‘0’.
11.16. Aux-Fed Subs
Driving the PA system sub bass speakers with their own mix has two main advantages. First, the mix
is much cleaner because only sources that generate the low frequencies, e.g. kick drum, bass guitar
and keyboards, are sent to the subs. Low frequency bleed from these sources into open microphones
such as vocals and snare is eliminated from the PA much more effectively than using just channel
filters. Second the subs bass amplifier is only working with the sources needed. It is not wasting power
reproducing unnecessary pickup.
The sub can be separately driven in several ways, for example using in a group, a mono or ’C‘ bus, or
using an aux. Using an aux send has become a popular method on the smaller consoles. Simply feed
the LR to a stereo crossover to drive the top speakers, and a post-fade aux send to a mono crossover
to drive the sub speakers. Refer to the speaker manufacturer for recommended crossover frequency,
usually within the range 80HZ to 120Hz. Align the system so that the normal unity gain position of the
channel fader and aux send result in the correct speaker balance.
For sources you wish to send to the sub, turn up the channel aux send to its unity 3 o’clock position.
Avoid the temptation to ride the aux send to create mono or less sub as this may upset the natural
speaker balance or cause problems for listeners in different parts of the room.
One problem with using the aux in this way is that it becomes difficult to balance the top and sub
speakers if you need to adjust the overall volume of the PA. Typically the LR (tops) uses fader
masters, and the aux is on rotary master. The mixing console overcomes this with an innovative mode
switch above the master faders that routes the AUX6 mix master through the M fader and on to the
XLR output. This switch is recessed for protection against accidental operation. The result is you get
three master fader aligned for simultaneous control, individual mutes, AFL and meters, and three
properly balanced XLR outputs. Note that the AUX6 rotary master does not affect the sub feed. IT
does however independently affect the AUX6 jack output. This gives you a further advantage that
another sub can be separately controlled using the rotary master, for example to supplement the stage
monitor mix.
11.17. Creating a separate C mix
As with the aux-fed sub mix described above, you can set the mode switch to create an independent
mix feeding a dedicated centre or mono speaker. The channel AUX6 sends become the routing to this
mix while the M fader with XLR output becomes the master, correctly aligned with L and R faders. Set
the channel aux sends to unity 3 o’clock position, and release the LR routing switches if you do not
want the signal in the LR speaker as well. The mixing console gives you the choice of either mixing