FEATURES

• Four models for low-impedance applications

• ISA 1350 drives 70V lines directly with 1500 watts / channel

• Three "Ti" versions include low-impedance and isolated 25, 70, and 100 volt outputs for distributed audio systems

• Rear panel gain controls for tamper resistant operation with 2 dB detents for quick and repeatable settings

• XLR and detachable Euro style input connectors

• DataPort V2 for use with DPV2-compatible signal processing accessories (XC-3, SF-3, LF-3) and DSP-3/DSP-4 (with external power supply)

• Independent defeatable clip limiters for reduced distortion

• Selectable high-pass filters protect speakers and prevent speaker transformer saturation with minimal effect on program material (30 Hz or 70 Hz on non-"Ti" models, 50 Hz or 75 Hz on "Ti" models)

• Class H complementary bipolar output circuitry reduces AC power draw and waste heat by 40% on ISA 750 and 800Ti, and by 50% on ISA 1350

• Front panel indicators include power, signal, and clip (and protect on ISA 1350)

• Covered barrier strip output connectors for safety agency compliance

• Automatic variable-speed fan for quiet normal operation with maximum cooling on demand

• Rear-to-front air flow keeps equipment racks cool

• Stereo, Bridge, or Parallel operating modes

• Comprehensive protection circuitry including DC, infrasonic, thermal overload and short circuit protection

• 3-year warranty plus optional 3-year extended service contract

"Ti" Models

• 25, 70, 100 volt, and low-impedance outputs available simultaneously

• Simple barrier strip connection determines output mode

• "Ti" models have fully isolated 25, 70, and 100 volt outputs

 

ISA SERIES AMPLIFIERS

• ISA 280

• ISA 450

• ISA 750

• ISA 1350

• ISA 300Ti

• ISA 500Ti

• ISA 800Ti

 

DOCUMENTS

ISA Users Manual (PDF 13MB)
ISA Specifications (PDF 143K)
 

HI-RES IMAGES

Front Panel (4572x1426, 928K) 
Rear Panel (4200x1456, 1MB) 
Rear Panel (Ti models) (4438x1582, 1.1MB) 
 

RESOURCES

Architect's & Engineer's Specifications
Loudspeaker Impedance Calculator
 

ACCESSORIES

Handle:
3RU

DataPort Accessories:
DSP-3* | DSP-4* | DPX-4 | DDI-3

Analog Signal Processing:
Crossovers: XC-3

Low Frequency: LF-3

Subwoofer: SF-3

Limiters/Attenuators:
SPA-3* 

*Requires External Power, DPX-1 Recommended
 

RoHS Compliant

 

SPECIFICATIONSISA280ISA450ISA750ISA1350ISA300TiISA500TiISA800Ti

 STEREO MODE, Both Channels Driven

8 ohms 20 Hz-20 kHz 0.1% THD185W260W450W800W185W260W450W

4 ohms 20 Hz-20 kHz 0.1% THD280W425W650W1300W280W425W650W

2 ohms 1 kHz 1% THD430W700W1200W2000W430W700W1200W

 DIRECT POWER, STEREO MODE

70V 20 Hz-20 kHz +0/-0.3 dB 0.5% THD---1500W---

 XF OUTPUT POWER, STEREO MODE

70V or 100V 50 Hz-16 kHz 0.5% THD----300W500W800W

25V 50 Hz-16 kHz 0.5% THD----200W300W500W

 BRIDGED MONO MODE

8 ohms 1 kHz 0.1% THD600W900W1500W2800W600W900W1500W

4 ohms 1 kHz 1% THD830W1400W2400W4000W830W1400W2400W

 XF OUTPUT POWER, BRIDGED MONO MODE

140V or 200V 50 Hz-16 kHz 0.5% THD----600W1000W1600W

Signal to Noise (20 Hz-20 kHz)100 dB100 dB100 dB100 dB100 dB100 dB100 dB

Distortion (SMPTE-IM)Less than 0.01%Less than 0.01%Less than 0.02%Less than 0.01%Less than 0.01%Less than 0.01%Less than 0.02%

Input Sensitivity @ 8 ohms1.15v
(+3.4 dBu)1.07v
(+2.8 dBu)1.07v
(+2.8 dBu)1.24v
(+4.1 dBu)1.15v
(+3.4 dBu)1.07v
(+2.8 dBu)1.07v
(+2.8 dBu)

Voltage Gain @ 8 ohms

 33.4x
(30.5 dB)44.7x
(33 dB)56.2x
(35 dB)64.0x
(36.1 dB)33.4x
(30.5 dB)44.7x
(33 dB)56.2x
(35 dB)

Output CircuitryClass ABClass ABClass HClass H, 3 TierClass ABClass ABClass H

THX Approved-----

Weight - Net

 36 lbs
(16.3 kg)42 lbs
(19 kg)47 lbs
(21.3 kg)68 lbs
(30.8 kg)44 lbs
(20.0 kg)49 lbs
(22.3 kg)57 lbs
(26 kg)

Weight - Shipping

 42 lbs
(19.1 kg)48 lbs
(22 kg)53 lbs
(24.0 kg)77 lbs
(34.4 kg)50 lbs
(22.7 kg)55 lbs
(25 kg)63 lbs
(28.6 kg)

 ALL MODELS

Distortion (Typical)
  20 Hz-20 kHz: 10 dB below rated power
  1.0 kHz and below: full rated powerLess than 0.03% THD, 4 ohms and 8 ohms

Less than 0.03% THD, 4 ohms and 8 ohms

Frequency Response
10 dB below rated output power

 ISA 280, 450, 750 and 1350: 
20 Hz-20 kHz, +0/-1 dB; -3 dB points: 5 Hz and 50 kHz
 ISA 300Ti, 500Ti and 800Ti: 
Direct outputs: -3 dB @ 50 Hz, -0.5 dB @ 20 kHz; XF outputs: 50 Hz-16 kHz, +1/-3 dB

Damping Factor (direct outputs)Greater than 200 at 8 ohms, ISA 1350 greater than 250

Output Regulation (isolated outputs)Less than 1.5 dB

Input Impedance10 k ohms unbalanced, 20 k ohms balanced

Input Clipping10 Vrms (+22 dBu)

CoolingContinuously variable speed fan, back-to-front air flow

Connectors, each channel
 Input: Active balanced; 3-pin Euro-style detachable terminal block and XLR (pin 2+)
Output: Covered barrier strips 
DataPort V2: HD-15 connector

Controls
 Front: AC switch
Rear: Ch. 1 and Ch. 2 gain knobs, 10-position DIP switch

Indicators
 PWR-ON: Green LED; SIGNAL: Green LED (1 per channel);
CLIP: Red LED (1 per channel)

Dimensions
 19" (48.3 cm) rack mounting, 5.25"(13.3cm) tall (3 rack spaces), 
15.9" (40 cm) deep (from front mounting rails)

Amplifier ProtectionFull short circuit, open circuit, thermal, ultrasonic, and RF protection;
Stable into reactive or mismatched loads

Power Requirements120, 230, VAC, 50-60 Hz

Load ProtectionOn/off muting; Triac crowbar: ISA 750, 1350 and 800Ti; AC coupling: ISA 280, 300Ti, 450 and 500Ti

All Specification Subject to Change Without Notice.

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