Toa AX-1000A, Руководство по эксплуатации

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Channel Signal Flow (simplified)
Logic Output
Direct Output
Mute
Terminals
Input
Ch. 1
Threshold Adjustment
The heart of an automatic mixer is the circuit that determines which inputs should gate on and which inputs should
remain off. The AX-1000A does this by comparing constantly and rapidly an individual channel's level and the
levels of all the inputs. This adaptive threshold system results in very smooth mixing.
Channel threshold determines how easily an input gates 'on'. Once the channel is 'on', the gating circuit
incorporates a preset Hold, 200 msec long, to keep the mic channel open between words as an individual speaks.
Channel threshold settings will vary from installation to installation since they depend on the acoustics of the site. If
Threshold is set too low (too sensitive), ambient noise may cause a channel's gate to flutter open and closed
randomly. If it is too high, the input will not gate open reliably when presented with a low-level signal. However,
these represent extremes. The AX-1000A's mixing circuitry works well over a range of 'middle ground' threshold
settings.
If the Threshold control is turned fully counter-clockwise, the channel remains on all the time.
Off-Attenuation
When a channel gates 'off', the output of the channel is attenuated. The factory setting is maximum attenuation, 40
dB. This is considered 'completely inaudible' for all practical purposes.
There may be applications in which an absence of ambient noise in the mix would be objectionable, or
where switching to full-attenuation would sound overly disruptive. Therefore, the Off-Attenuation may be set
at a lower level, such as 10 to 15 dB.
You may have other applications where less-than-full channel attenuation is desirable.
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