Crown Com-Tech 1610, Руководство по обслуживанию

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Com-Tech 810 and 1610 Amplifier Service Manual
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2-6
Rev. 0
Crown specifications are guaranteed for three years.
In an effort to provide you with as much information as possible about the high power-producing capabilities of your amplifier, we have
created the following power matrices.
Minimum Guaranteed Power Specifications
Crown’s minimum power specifications represent the absolute smallest amount of output power you can expect from your amplifier when
it is driven to full output under the given conditions. Some spaces in each matrix may be left blank because the same guarantee is not
provided for those conditions—however, your amplifier will perform well under all conditions listed in each matrix.
When measuring power, 0.1% THD appears to be the industry standard for distortion. Two of the maximum average power specifications
shown in each minimum power matrix are measured at 0.1% THD so you can easily compare Crown specifications to those of other
manufacturers. But this high level of distortion actually allows for some clipping which is undesirable. Because of this, a maximum average
power specification at 0.05% THD is included in each minimum power matrix which represents non-clipped conditions. Although most
manufacturers do not give you power specifications at 0.05% THD, we encourage them to provide these specifications so you will have a
more realistic representation of the way amplifiers should be used in the real world—without a clipped output signal.
Many manufacturers publish power specs with a tolerance of ±1 dB or worse. This means their amplifier can deviate more than 20% in
output! A 100 watt amplifier would meet their specification if it only produced 79.4 watts. Other manufacturers qualify their specs by saying
Figure 2.6 Com-Tech 810 Minimum Power Matrix
they are “typical,” “subject to manufacturing toler-
ances,” “single channel driven” or that they are
specified with “fuses bypassed.” Each of these
statements effectively removes any performance
guarantee. In fact, some manufacturers use these
tactics to generate large power numbers, and
they don’t even print a disclaimer. We take a dif-
ferent approach at Crown—our amplifiers are
guaranteed to meet or exceed their specifications
for three years. Further, because our published
specs are set below our “in-house” measure-
ments, you can expect
every Crown amplifier to
meet
or exceed
its published minimum power
specs. We believe you should get what you pay
for.
Minimum Power Notes:
All minimum power specifications are based on
0.5% regulated AC mains with THD of less than
1.0% and an ambient room temperature of 70° F
(21° C). Standard EIA power (RS-490) is not shown
here because it is identical to FTC Continuous Av-
erage Power.
1. A 1 kHz sine wave is presented to the amplifier
and the output monitored for nonlinear distor-
tion. The level is increased until THD reaches
0.1%. At this point, average power per chan-
nel is reported.
2. A sine wave is presented to the amplifier over
the range from 20 Hz to 20 kHz and the output
monitored for nonlinear distortion. The level at
each frequency is increased until THD reaches
0.1%. At this point, average power per chan-
nel is reported.
3. A 1 kHz sine wave is presented to the amplifier
and the output monitored for nonlinear distor-
tion. The level is increased until THD reaches
0.05%. At this point, average power per chan-
nel is reported.
4. Continuous power in the context of Federal
Trade Commission testing is understood to be
a minimum of five minutes of operation. Har-
monic distortion is measured as the RMS sum
total and given as a percentage of the funda-
mental output voltage. This applies for all watt-
ages greater than 0.25 watts.
Com-Tech 810 – Minimum Guaranteed Power (Watts)
Dual/Mono
Mode
Dual
(both channels
driven)
Bridge-Mono
(balanced output)
Parallel-Mono
FTC Continuous Average
At 0.1% THD
(See note 4)
1 kHz 20Hz-20kHz
Maximum Average
Load in Ohms
(Constant Voltage)
AC Mains
120 VAC, 60 Hz
1 kHz
At 0.1% THD
(See note 1)
At 0.1% THD
(See note 2)
20Hz-20kHz
Dual
(both channels
driven)
Bridge-Mono
(balanced output)
Parallel-Mono
At 0.05% THD
(See note 3)
1 kHz
100/120 VAC, 50/60 Hz
Dual
(both channels
driven)
Bridge-Mono
(balanced output)
Parallel-Mono
220/240 VAC, 50/60 Hz
12.5 (70V)
4
2
25 (140V)
8
6.25 (70V)
8
4
16
12.5 (70V)
4
2
25 (140V)
8
6.25 (70V)
8
4
16
12.5 (70V)
4
2
25 (140V)
8
6.25 (70V)
8
4
16
490
305
460
975
610
920
965
610
915
460
300
425
925
600
855
925
600
855
485
310
440
965
620
885
940
615
875
460
295
455
935
600
905
440
290
415
885
580
825
470
305
430
920
605
855
480
300
455
965
605
905
950
600
905
460
295
420
915
595
850
920
595
845
485
310
435
955
615
875
930
610
870
470
300
450
950
605
905
950
605
910
445
295
410
890
595
830
895
595
830
465
310
425
930
615
865
920
600
855
455
290
445
905
600
880
425
290
400
840
575
800
450
300
420
875
600
840