Toa RXA-212, Руководство по эксплуатации

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Feedback Prevention
When the overall gain of a sound system is increased, feedback will occur at frequencies where
the system response has peaks. Suppose the system has uneven frequency response like that
shown in the following diagram.
The frequency at which feedback will occur when gain is increased is about 500Hz. In this
case, feedback may be prevented by attenuating levels at 500Hz by 3dB to 5dB with an
equalizer. If the overall gain is again gradually increased, feedback will occur next at about
125Hz. It may be stopped by attenuating the levels 3dB to 5dB at that frequency. In this
procedure, sufficient gain in the sound system is obtained before feedback.
Frequency Response (Measurement of source impedance 150
ohms)
LINE OUT (CH IN — LINE OUT) at +4dB*
+0dB, –0.5dB 50Hz to 15kHz
+0dB, –2dB 20Hz to 30 kHz
SPEAKER OUT (EXT IN — SPEAKER OUT) at 1W
+0dB, –0.5dB 30Hz to 30kHz
+0dB, –1.5dB 20Hz to 60kHz
Total Harmonic Distortion
LINE OUT
0.3% (+4dB*/600 ohms at 1kHz)
0.05% (+20dB*/600 ohms at 1kHz)
SPEAKER OUT
0.025% (120W/8 ohms at 1kHz)
0.3% (120W/8 ohms 20Hz to 20kHz)
Power Output
120W/8 ohms
Hum and Noise
LINE OUT (Input termination of 150 ohms, Input level sw at
BAL -60, Trim at "0", output termination of 600 ohms)
Equivalent Input Noise
-126dB* (20Hz — 20kHz)
-128dB* (IHF-A weighted)
S/N (Program fader and one input fader at nominal)
66dB (20Hz — 20kHz)
68dB (IHF-A weighted)
SPEAKER OUT (EXT Input short circuit, sensitivity
switch at "+4dB", output termination of 8 ohms)
Equivalent Input Noise
-104dB* (20Hz — 20kHz)
–111dB* (IHF-A weighted)
S/N
108dB (20Hz — 20kHz)
115dB (IHF-A weighted)
Maximum Voltage Gain
104dB CH IN to SPEAKER OUT
76dB CH IN to LINE OUT (PGM, FB)
82dB CH IN to ECHO SEND (+4)
56dB CH IN to REC OUT
Channel Equalizer (+15dB maximum)
LOW 100Hz Shelving
LOW MID 300Hz Peaking
HI-MID 3kHz Peaking
HIGH 10kHz Shelving
Graphic Equalizer (±12dB maximum)
Center Frequency
63Hz, 125Hz, 250Hz, 500Hz, 1kHz, 2kHz,
4kHz, 8kHz, 16kHz
Crosstalk
60dB at 1kHz, input to output
Internal Echo Unit
Delay Time SHORT 12msec— 40msec
LONG 40msec— 140msec
Peak Indicator
LED built into each input channel turns on when the pre-
fader, post EQ signal reaches 6dB before clip.
LED built into each built-in power amplifier turns on when
the output level reaches 3dB before nominal.
Meter ("0" = +4dB* output at LINE OUT)
2 pairs of fluorescent bargraph meter for PGM L, R AND FB
1,2.
Power Consumption
RXA-212 260W
RXA-216 500W
Finish
Black panel, rosewood trim
Dimensions (W×D×H)
RXA-212
574 × 751 × 206 mm 22-5/8" × 29-5/8" × 8-1/8"
RXA-216
694 × 751 × 206 mm 27-3/8" × 29-5/8" × 8-1/8"
Weight
RXA-212 29kg (64 lbs)
RXA-216 40kg (88 lbs)
Accessory
Fuse
*0dB is referenced to 0.775V RMS
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Channel and Graphic Equalizers
General Specifications (RXA-212, RXA-216)
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