The D25 amplifier

Overview

The d&b D25 amplifier is a four-channel Class D amplifier featuring Digital Signal Processing (DSP) for advanced loudspeaker-specific configurations, equalization, and delay functions. It offers a dynamic range of 112 dB (unweighted) and is designed to drive high-voltage d&b loudspeakers, providing comprehensive management and protection.

The user interface includes a 4.3" (480 x 272 pixels) color touchscreen and a digital rotary encoder for configuration and status monitoring. The D25 incorporates enhanced energy-saving features and Automatic Wake-up for environmental responsibility.

Signal Processing and Connectivity

The amplifier supports advanced signal processing, including user-definable 16-band EQs and a delay capability of up to 10 seconds. The DSP unit has a fixed latency of 0.3 ms.

Connectivity includes one redundant Milan™™ Listener stream (up to eight channels), eight Milan inputs, four analog inputs, four AES3 inputs with link outputs, and two Ethernet ports (1 Gbit/100 Mbit) for remote control and system integration via d&b ArrayCalc and R1 Remote software. It supports the OCA/AES70 protocol.

A flexible Fallback structure ensures the transmission of a secondary signal when needed. For applicable d&b loudspeakers, d&b LoadMatch preserves tonal balance with cable lengths up to 70 m (230 ft).

Power and Protection

The D25 utilizes a switch-mode power supply with automatic mains range selection and active Power Factor Correction (PFC) for efficient and clean current draw. It features overvoltage and undervoltage protection, inrush current limiter, and internal fuse protection.

Protection circuits include overcurrent, DC offset, HF voltage limiter, and pop-noise suppression. Temperature-dependent fan control ensures cooling, with self-resetting overtemperature protection.

Specifications

Operating Conditions

• Operating temperature: -10 °C to +40°C (continuous), +50°C (short-term)
• Storage temperature: -20 °C to +70 °C
• Humidity (non-condensing): < 70%
• Maximum height: 2000 m / 6560 ft

Power Supply

• Switched-mode power supply with automatic mains range selection and active PFC
• Mains connector: powerCON® TRUE 1 TOP
• Rated mains voltage: 100-127 V / 208-240 V
• Rated mains current: 20 A / 13 A

Audio Power Outputs

• 4 x NL4 for SPEAKER OUTPUTS A/B/C/D
• 2 x NL4 for MIX TOP/SUB and/or 2-WAY ACTIVE modes
• 1 x NL8 for 4 CHANNEL OUTPUT
• Maximum output voltage/current: 120 Vpeak / 35 Apeak
• Output power rating (EIA-426B noise CF 12 dB): 4 x 900 W/8 Ω, 4 x 1800 W/4 Ω

Output Noise/Dynamic Range

• Output noise (BW 20 kHz): 350 µVRMS (analog input)
• Dynamic range (BW 20 kHz, reference 180 Vpk): 114 dB (analog input, A-weighting)

THD+N/Crosstalk

• THD+N (unweighted, 20 - 20 kHz): < -86 dB / 0.005%
• Crosstalk (20 - 20 kHz): < -70 dBr

Dimensions and Weight

• Height x width x depth: 2 RU x 19" x 512 mm (20.2")
• Weight: 13.8 kg / 30.4 lb

Features and Benefits

• Increases overall system efficiency
• Advanced voltage management
• Energy-efficient for minimal ecological impact
• Enhanced DSP capabilities accommodate future system architecture

Applications

• International Touring and Rental
• Musical theatre rental
• Corporate and industrial rental

Controls and Indicators

• POWER: Mains power switch
• SCROLL/EDIT: Digital rotary encoder
• TFT color touchscreen: 4.3" / 480 x 272 pixels

Fan Noise Emission

• Rack mounted, measured on axis, 1 m (3.3 ft) to front panel, A-weighting.
• Min./Max. RPM: 30/50 dB(A)
• Ambient temperature: 23 °C / 73.4 °F

Dimensions Diagram

Diagram showing the physical dimensions of the D25 amplifier in millimeters and inches. Key dimensions include:

• Width: 467 mm [18.4 in]
• Depth: 483 mm [19 in]
• Height: 442.5 mm [17.4 in]
• Overall depth with connectors: 460.5 mm [18.1 in]
• Total depth: 485 mm [19.1 in]
• Maximum depth: 512 mm [20.2 in]
• Front panel height: 37.6 mm [1.5 in]
• Front panel width: 9.5 mm [0.4 in]