QSC ISA 280, Technical & Service Manual

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Technical Service Manual 5
ISA Series Power Amplifiers
ISA Series Performance Specifications
ISA280 & ISA300Ti ISA450 & ISA500Ti ISA750 & ISA800Ti ISA1350
OUTPUT POWER in watts
FTC: 20 Hz–20 kHz @ 0.1% THD, both channels driven, direct outputs
8W per channel 185 260 450 800
4W per channel 280 400 650 1300
FTC: 50 Hz–16 kHz @ 0.5% THD, both channels driven, transformer outputs
70V or 100V (per channel) 300 (ISA 300Ti) 500 (ISA 500Ti) 800 (ISA 800Ti)
25V (per channel) 240 (ISA 300Ti) 400 (ISA 500Ti) 640 (ISA 800Ti)
FTC: 20 Hz–20 kHz @ 0.5% THD, both channels driven, direct outputs
70V (per channel) 1500
EIA: 1 kHz @ 0.1% THD, both channels driven
8
Ω
per channel 200 280 500 850
4
Ω
per channel 300 450 750 1400
1 kHz @ 1% THD, typical, both channels driven
2
Ω
per channel 430 700 1200 2000
Bridge Mono:
8
Ω
, 20 Hz–20 kHz, 0.1% THD 530 800 1300 2600
8
Ω
, 1 kHz, 0.1% THD 600 900 1500 2800
4
Ω
, 1 kHz, 1% THD, typical 830 1400 2400 4000
140V or 200V, 50 Hz–16 kHz, 0.5% THD 600 (ISA 300Ti) 1000 (ISA 500Ti) 1600 (ISA 800Ti)
140V, 20 Hz–20 kHz, 0.5% THD (direct outputs) 3000
50V, 50 Hz–16 kHz, 0.5% THD 480 (ISA 300Ti) 800 (ISA 500Ti) 1280 (ISA 800Ti)
DYNAMIC HEADROOM 2 dB @ 4
Ω
2 dB @ 4
Ω
2 dB @ 4
Ω
2 dB @ 4
Ω
DISTORTION
SMPTE-IM < 0.01% < 0.01% < 0.02% < 0.02%
FREQUENCY RESPONSE 20 Hz–20 kHz, +0/-1 dB
(at 10 dB below rated output power) -3 dB points: 5 Hz and 50 kHz
DAMPING FACTOR > 300 @ 8
Ω
> 300 @ 8
Ω
> 300 @ 8
Ω
> 250 @ 8
Ω
NOISE (unweighted 20 Hz to 20 kHz, below rated output) 100 dB 100 dB 100 dB 100 dB
VOLTAGE GAIN 31.6× (30 dB) 40× (32 dB) 50× (34 dB) 64× (36 dB)
INPUT SENSITIVITY, V RMS
full rated power @ 8
Ω
1.15v (+3.4 dBu) 1.15v (+3.4 dBu) 1.23v (+4.0 dBu) 1.24v (+4.1 dBu)
7. Schematics and diagrams ..................................................................................................................................................71
7.1 ISA Series Chassis Assemblies ...................................................................................................................................................................... 71
7.2 ISA280 (1st generation) Schematics ............................................................................................................................................................. 94
7.3 ISA280 (revised) Schematics ........................................................................................................................................................................... 97
7.4 ISA300T Schematics ......................................................................................................................................................................................... 100
7.5 ISA300Ti Schematics ........................................................................................................................................................................................ 103
7.6 ISA450 (1st generation) Schematics ........................................................................................................................................................... 106
7.7 ISA450 (revised) Schematics ......................................................................................................................................................................... 109
7.8 ISA500T Schematics ......................................................................................................................................................................................... 112
7.9 ISA500Ti Schematics ........................................................................................................................................................................................ 115
7.10 ISA750 (1st generation) Schematics ........................................................................................................................................................ 118
7.11 ISA750 (revised) Schematics ...................................................................................................................................................................... 121
7.12 ISA800T Schematics ...................................................................................................................................................................................... 124
7.13 ISA800Ti Schematics ..................................................................................................................................................................................... 127
7.14 ISA750, ISA800T, ISA800Ti Component locations .................................................................................................................................. 130
7.15 ISA1350 Schematics ....................................................................................................................................................................................... 132
7.16 ISA1350 Component locations .................................................................................................................................................................... 136
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