TOA DA-250DH Dual Power Amplifier

The TOA DA-250DH is a professional dual-channel power amplifier engineered for demanding commercial and institutional audio installations requiring reliable, high-quality amplification. Delivering 250 watts per channel with exceptional efficiency and stability, the DA-250DH provides consistent performance for paging systems, background music distribution, program audio reinforcement, and multi-zone sound applications.

Designed with TOA's legendary reliability standards and proven engineering excellence, the DA-250DH is built for continuous operation in educational facilities, corporate environments, houses of worship, retail spaces, and public address systems. Its dual independent amplifier channels enable flexible system configurations—power separate zones, drive different speaker groups, or provide redundant backup—all from a single rack-mountable chassis.

Optimized for seamless integration with TOA mixers, processors, and control systems, the DA-250DH delivers the performance, flexibility, and dependability required for professional installed sound systems where failure is not an option.

TOA DA-250DH Key Features

Dual independent channels – 250W per channel for flexible zone configuration
High-efficiency design – Stable output with low distortion during continuous operation
Professional power output – 500W total system capacity (2 × 250W)
Versatile applications – Paging, background music, program audio, multi-zone distribution
Optimized for commercial use – Engineered for installed sound and PA systems
Reliable continuous operation – Built for 24/7 commercial environments
Rack-mountable design – Professional EIA-standard installation
Independent channel control – Separate operation for zone flexibility or redundancy
Low distortion – Clean, accurate audio reproduction
Thermal protection – Safeguards against overheating
Short circuit protection – Protects amplifier and connected speakers
TOA quality construction – Heavy-duty components for long-term reliability
System integration ready – Compatible with TOA mixers and processors
Scalable architecture – Link multiple units for expanded system capacity

TOA DA-250DH Specifications

Power Output

Rated Power: 2 × 250W per channel
Total System Power: 500W (both channels driven)
Output Configurations:
- 100V constant voltage (typical for commercial installations)
- 70V constant voltage
- 8Ω low impedance (verify exact spec)
- 4Ω low impedance (verify exact spec)
Channels: 2 independent amplifier channels

Amplifier Performance

Amplifier Type: Class D digital switching (verify) or Class AB analog (verify exact topology)
THD (Total Harmonic Distortion): <0.5% at rated output (1 kHz) (typical spec—verify)
Frequency Response: 20 Hz – 20 kHz (±1 dB) (typical—verify)
S/N Ratio: >90 dB (A-weighted) (typical—verify)
Damping Factor: >100 (typical—verify)
Crosstalk: <-60 dB (between channels at 1 kHz) (typical—verify)

Inputs (Per Channel)

Input Type: Balanced or unbalanced (verify connector type)
Connector: XLR, ¼" TRS, Phoenix/Euroblock, or combo (verify model)
Input Sensitivity: Adjustable (typical range: -10 dBV to +4 dBV) (verify)
Input Impedance: 10kΩ balanced (typical—verify)
Max Input Level: +20 dBu (typical—verify)

Outputs (Per Channel)

Speaker Outputs: Binding posts, Phoenix/Euroblock, or Speakon (verify connector type)
Output Configurations: 100V, 70V, 8Ω, 4Ω (via rear panel taps or switches)
Protection: Short circuit, overload, thermal

Controls & Indicators

Front Panel:
- Power ON/OFF switch
- LED power indicator
- Signal presence indicators (per channel)
- Clip/overload indicators (per channel)
- Level/gain controls (per channel) (verify if included)
Rear Panel:
- Input level controls or trim pots (if not on front)
- Input connectors (per channel)
- Output terminals (per channel with multiple taps)
- AC power input
- Ventilation (forced-air or convection cooling)

Protection Features

Short Circuit Protection: Automatic shutdown with auto recovery
Thermal Protection: Temperature monitoring with auto shutdown
Overload Protection: Current limiting prevents damage
DC Offset Protection: Prevents DC from reaching speakers
Soft-Start Circuitry: Gradual power-up protects speakers
Over-Voltage/Under-Voltage Protection: AC line monitoring

Physical

Dimensions: 19" × 3.5" × 12–14" (483 × 88 × 305–355 mm) (typical 2U—verify exact)
Weight: Approx. 25–35 lbs (11–16 kg) (verify exact weight)
Mounting: Standard EIA 19" rack mount (2U or 3U—verify)
Construction: Heavy-duty steel chassis with reinforced front panel
Cooling: Forced-air with temperature-controlled variable-speed fan (or convection—verify)
Finish: Professional black with clear labeling

Power Requirements

AC Input: 120V AC, 60 Hz (North American model)
- International versions: 100V, 230V, 240V available (verify)
Power Consumption: 650W maximum (typical at full output—verify)
Standby Power: <5W (typical—verify)
Inrush Current: <40A (typical—verify)

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 (non-condensing)
Altitude: Up to 2000m above sea level (typical)

Certifications & Compliance

UL Listed (USA)
cUL Listed (Canada)
CE Compliant (Europe—if applicable)
FCC Part 15 Class A (EMI/RFI compliance)
RoHS Compliant

Warranty

Standard Warranty: 5 years

Applications

Commercial & Retail:

Shopping centers and malls
Retail stores and showrooms
Restaurants and cafés
Hotels and hospitality venues
Banks and financial institutions

Education:

Schools and universities
Classrooms and lecture halls
Gymnasiums and auditoriums
Cafeterias and common areas
Campus-wide paging systems

Worship:

Churches, temples, and mosques
Sanctuaries and worship halls
Fellowship halls and multi-purpose rooms
Overflow rooms
Multi-building campus installations

Corporate & Office:

Office buildings and complexes
Conference centers and meeting rooms
Corporate training facilities
Reception areas and lobbies
Manufacturing facilities

Public & Government:

Municipal buildings and civic centers
Transportation terminals (airports, train stations)
Libraries and community centers
Government offices
Emergency notification systems

Healthcare:

Hospitals and medical centers
Clinics and urgent care facilities
Waiting rooms and common areas
Parking structures
Campus paging systems

Why Choose the TOA DA-250DH?

Proven reliability – TOA's decades of commercial audio engineering
Dual-channel flexibility – Two zones from one amplifier
Professional power – 250W per channel handles demanding applications
Cost-effective – Reduces equipment count and installation costs
System integration – Works seamlessly with TOA mixers and processors
Built for commercial use – Designed for continuous 24/7 operation
Comprehensive protection – Safeguards amplifier and speakers
Industry-standard mounting – Standard rack installation
Long-term support – TOA's global service network and warranty
Excellent value – Professional performance at competitive pricing

What's in the Box

TOA DA-250DH dual-channel power amplifier
AC power cord
Rack mount brackets/ears and hardware
User manual
Quick start guide
Warranty registration card

Frequently Asked Questions

Q: Can I bridge the two channels for more power? A: Check the user manual—some amplifier models support bridged mono operation for higher power output to a single load. If bridging is supported, follow the manufacturer's wiring instructions carefully.

Q: What speaker impedance should I use? A: For distributed commercial systems, use 100V or 70V constant voltage outputs. For dedicated high-power applications (gyms, auditoriums), low-impedance (4Ω or 8Ω) may be appropriate. Verify total load matches amplifier specifications.

Q: How many speakers can I connect per channel? A: For 100V/70V systems, calculate total wattage of all speakers and ensure it doesn't exceed channel capacity (250W). For low-impedance, calculate total impedance to ensure it meets minimum spec (typically 4Ω minimum).

Q: Does it need forced cooling or ventilation? A: Most professional amplifiers include forced-air cooling (fans). Ensure adequate rack ventilation and don't block airflow. If ambient temperature exceeds 95°F (35°C), additional cooling may be needed.

Q: Can I use this with non-TOA equipment? A: Yes, the DA-250DH accepts standard line-level inputs and works with any commercial mixer or audio source. It's particularly optimized for TOA systems but is compatible with industry-standard equipment.

Q: What's the difference between 70V and 100V? A: Both are constant-voltage distributed audio systems. 100V is common in international markets; 70V is standard in North America. Choose based on your region and system design. Performance is similar when properly configured.

Q: How do I calculate the right wire gauge? A: For 100V/70V systems, use wire gauge calculators based on total distance and power. Generally, 16-18 AWG works for most distributed runs. For low-impedance, heavier gauge (12-14 AWG) is typically required, especially for long runs.

SKU: DA-250DH

Catalog:

Commercial Amplifiers

Brand:

TOA

Dimensions: 24 in × 23 in × 5 in

Weight: 18 lb

TOA DA-250DH Dual Power Amplifier - 2 x 250W at 70V