The TOA DA-550F is a professional high-power 4-channel Class D digital amplifier engineered for demanding commercial audio installations requiring exceptional output capacity, advanced monitoring, and remote control capabilities. Delivering 550 watts per channel at 4Ω (2200W total system power), the DA-550F combines robust amplification with intelligent system integration features in a compact 2U rack chassis.

Designed specifically for AV integrators working on large-scale, mission-critical projects—including corporate campuses, educational facilities, hospitality venues, transportation hubs, and entertainment complexes—the DA-550F provides not just power, but comprehensive control and monitoring through dedicated Control/Monitor terminals. Real-time status tracking of power state, protection conditions, and fan operation enables proactive system management and simplified troubleshooting in complex installations.

Each channel features independent power sections for superior fault isolation and stable operation, while the advanced switching power supply architecture delivers exceptional efficiency with minimal heat generation—critical for high-power applications in dense equipment racks. The DA-550F's flexible output configurations (100V, 70V, and low-impedance) accommodate diverse speaker systems, making it an ideal choice for installations requiring powerful, monitored, remotely controllable amplification.

TOA DA-550F Key Features

  • High-power 4-channel design – 550W per channel at 4Ω (2200W total system capacity)
  • Advanced Class D technology – Superior efficiency with minimal heat generation
  • Independent power sections – Complete channel isolation for fault protection
  • Control/Monitor terminals – Remote system integration and status monitoring
  • Remote ON/OFF control – Per-channel or global power control via external systems
  • Real-time status monitoring – Track power state, protection status, and fan operation
  • Switching power supply – Lightweight, energy-efficient, reduced thermal output
  • Flexible output configurations – 100V, 70V, 25V constant voltage plus 4Ω/8Ω low-impedance
  • Custom control panel integration – Designed for integration with building automation
  • Professional 2U design – EIA-standard rack mounting for commercial installations
  • Multi-zone capability – Four independent high-power zones
  • Comprehensive protection – Short circuit, thermal, overload, and DC offset safeguards
  • Mission-critical reliability – Engineered for 24/7 continuous operation
  • Scalable architecture – Link multiple units for large-scale systems
  • Lightweight construction – Simplified installation despite high power output
  • System integration ready – Compatible with AMX, Crestron, and custom control systems

TOA DA-550F Specifications

Power Output

  • Rated Power (Per Channel):
    • 550W @ 4Ω
    • 400W @ 8Ω (typical—verify)
    • 550W @ 100V constant voltage
    • 550W @ 70V constant voltage
    • 550W @ 25V constant voltage (verify availability)
  • Total System Power: 2200W (all 4 channels driven at 4Ω)
  • Channels: 4 independent amplifier channels with isolated power sections

Amplifier Performance

  • Amplifier Type: Class D digital switching amplifier
  • THD (Total Harmonic Distortion): <0.5% at rated output (1 kHz) (typical—verify)
  • Frequency Response: 20 Hz – 20 kHz (±0.5 dB) (typical—verify)
  • S/N Ratio: >100 dB (A-weighted) (typical for high-power Class D—verify)
  • Damping Factor: >300 (typical for Class D—verify)
  • Crosstalk: <-75 dB (between channels at 1 kHz) (typical—verify)
  • Efficiency: >90% (typical Class D efficiency)
  • Slew Rate: High (typical for Class D—verify exact spec)

Inputs (Per Channel)

  • Input Type: Balanced or unbalanced (verify exact configuration)
  • Connector: Phoenix/Euroblock screw terminals or XLR (verify model)
  • Input Sensitivity: Adjustable (typical range: 0.775V to 1.4V for rated output)
  • Input Impedance: 10kΩ or 20kΩ balanced (typical—verify)
  • Max Input Level: +20 dBu (typical—verify)
  • Common Mode Rejection: >40 dB @ 1 kHz (for balanced inputs)

Outputs (Per Channel)

  • Speaker Outputs: Phoenix/Euroblock screw terminals (heavy-duty for high current)
  • Output Configurations
    • 100V constant voltage (high-impedance distributed systems)
    • 70V constant voltage (North American distributed systems)
    • 4Ω low impedance (high-power direct drive)
    • 8Ω low impedance (standard speaker impedance)
  • Independent Channel Operation: Each channel is fully independent
  • Output Current Capacity: High (verify exact specification for 550W @ 4Ω)

Control & Monitoring System

Control/Monitor Terminals:

  • Remote ON/OFF Control:
    • Per-channel power control via contact closure or voltage trigger
    • Global system power control option
    • Integration with building automation systems
    • AMX/Crestron/Extron compatible (via relay interface)
  • Status Monitoring Outputs:
    • Power Status: Indicates amplifier and per-channel power state
    • Protection Status: Signals when protection circuits activate (thermal, short, overload)
    • Fan Status: Monitors cooling system operation
    • Channel Status: Individual channel operational state
  • Connector Type: Phoenix/Euroblock screw terminals for reliable connections
  • Signal Type: Contact closure outputs or voltage levels (verify exact specification)
  • Custom Panel Integration: Requires user-supplied control/monitoring panel or integration with existing control system

Front Panel Controls & Indicators

  • Master Power Switch: ON/OFF with LED indicator
  • Per-Channel Indicators:
    • Signal presence (4 LEDs)
    • Clip/overload warning (4 LEDs)
    • Protection active (4 LEDs)
  • System Status Indicators:
    • Power LED
    • Thermal warning
    • Fan operation
  • Optional: Level meters or gain controls (verify model configuration)

Rear Panel

  • Input Connectors: 4-channel inputs (Phoenix/Euroblock or XLR)
  • Output Terminals: 4-channel outputs with voltage/impedance selection
  • Input Sensitivity Controls: Per-channel level adjustment
  • Control/Monitor Terminal Block: Multi-pin connector for remote control and monitoring
  • AC Power Input: IEC connector with locking mechanism
  • Forced-Air Ventilation: Intake and exhaust openings

Protection Features

  • Short Circuit Protection: Automatic per-channel shutdown with auto recovery
  • Thermal Protection:
    • Multi-point temperature monitoring
    • Intelligent fan speed control
    • Automatic shutdown at critical temperature
    • Status output for remote monitoring
  • Overload Protection: Current limiting with automatic recovery
  • DC Offset Protection: Prevents DC voltage from damaging speakers
  • Over-Voltage/Under-Voltage Protection: AC line monitoring
  • Soft-Start Circuitry: Gradual power-up protects speakers and limits inrush
  • Independent Channel Protection: Fault isolation—one channel issue doesn't affect others
  • Fan Failure Detection: Monitors cooling system operation

Power Supply

  • Type: High-efficiency switching power supply (SMPS) with PFC
  • Advantages:
    • Lightweight design (no heavy transformers)
    • High efficiency (>85% typical)
    • Wide AC input voltage tolerance
    • Reduced heat generation
    • Active power factor correction
    • Soft-start reduces inrush current

Physical

  • Dimensions: 19" × 3.5" × 16" (483 × 88 × 406 mm)
  • Weight: Approx. 22-30 lbs (10-14 kg)
  • Mounting: Standard EIA 19" rack mount (2U)
  • Construction: Heavy-duty steel chassis with reinforced structure
  • Cooling: Forced-air with temperature-controlled variable-speed intelligent fan
  • Finish: Professional black with clear labeling
  • Ventilation: Front-to-rear airflow
  • Handles: Optional rack handles for installation 

Power Requirements

  • AC Input: 120V AC, 60 Hz (North American model)
    • International versions: 100-240V AC, 50/60 Hz
  • Power Consumption:
    • Maximum: 2500W at full output
    • Idle: 50-80W (typical Class D standby)
    • Efficiency: >90% (significantly lower AC draw than Class AB)
  • Inrush Current: <40A
  • Power Factor: >0.95 (with PFC)
  • AC Input Fuse/Breaker: Internal protection 

Operating Conditions

  • Operating Temperature: 32°F – 104°F (0°C – 40°C)
  • Storage Temperature: -4°F – 122°F (-20°C – 50°C)
  • Humidity: 90% RH or less
  • Altitude: Up to 2000m above sea level
  • Ventilation Required: Minimum 2" side clearance, 8" rear clearance 

Certifications & Compliance

  • UL Listed
  • cUL Listed
  • CE Compliant
  • FCC Part 15 Class A
  • RoHS Compliant
  • ENERGY STAR 

Why Choose the TOA DA-550F?

  • High-power performance – 550W per channel handles demanding applications
  • Intelligent monitoring – Built-in status tracking and remote control
  • Mission-critical ready – Designed for applications where downtime is unacceptable
  • System integration – Native support for building automation and AV control
  • 4-channel efficiency – 2200W total in compact 2U chassis
  • Class D technology – High efficiency reduces energy costs and cooling requirements
  • Independent channels – Fault isolation ensures maximum reliability
  • Comprehensive protection – Multiple safeguards protect investment
  • TOA quality – Decades of professional audio engineering excellence
  • Scalable architecture – Build large systems with multiple units
  • Professional features – Designed for commercial integrators
  • Excellent value – Premium features at competitive pricing

Frequently Asked Questions

Q: What control and monitoring panels are compatible? A: The DA-550F provides contact closure and voltage outputs/inputs. You'll need to design a custom panel or integrate with existing control systems (AMX, Crestron, Extron, building automation). TOA provides wiring specifications but not pre-built panels.

Q: Can I monitor the amplifier remotely over a network? A: Not directly—the DA-550F provides hardwired control/monitoring terminals. For IP-based control, integrate with a control system processor (AMX, Crestron) that has network capability.

Q: How much cooling does a 2200W amplifier need? A: Class D efficiency (~90%) means approximately 220W heat output at full power. Ensure rack has adequate ventilation, consider rack fans, and maintain ambient temperature below 85°F (30°C).

Q: Can I bridge channels for more power? A: Check user manual for bridging capability. With 550W per channel already available, bridging is typically not needed for most commercial applications.

Q: What's the difference between this and the DA-500F-HL? A: Both offer high power output. Key differences may include control/monitoring features, output configurations, and specific power ratings. Consult TOA for detailed comparison.

Q: Do I need an electrician to wire the control terminals? A: Low-voltage control wiring is typically within the scope of AV technicians, but verify local codes. AC power installation should follow electrical codes and may require licensed electrician.

Q: What happens if fan fails? A: The monitoring output will signal fan failure. Thermal protection will activate sooner without cooling. The amplifier will shut down before damage occurs. Fan should be serviced/replaced immediately.

Q: Can I use this for live sound reinforcement? A: Yes, the DA-550F's high power and low distortion make it suitable for live sound applications, though dedicated touring amplifiers may offer additional features like DSP and network control.

List price: $4,075.00
Price: $3,294.00
SKU: DA-550F
Catalog: 
Commercial Amplifiers
Brand: 
TOA
Dimensions: 24 in × 24 in × 6 in
Weight: 22 lb