The Ahuja NBA-15 portable neckband public address amplifier is engineered with standard audio and electrical interfaces to support mobile voice reinforcement alongside external auxiliary audio reproduction. Designed for commercial training, teaching, tour group coordination, and instructional presentations, the amplifier incorporates dedicated connection ports for both dedicated microphone transducers and line-level playback devices.
Microphone Input and Transducer Compatibility
The unit features a dedicated 3.5 mm (Ø 3.5mm) microphone input socket calibrated for low-level microphone signals. The Mic-1 channel features an input sensitivity of 1.0 mV, engineered to match the supplied headband microphone. The microphone assembly utilizes a cardioid condenser transducer element, delivering directional acoustic capture that suppresses off-axis environmental noise and reduces feedback loops across the system's operational frequency range of 80 Hz to 12,000 Hz.
Line-Level Audio Source Integration
For multimedia playback and background audio distribution, the NBA-15 includes an independent 3.5 mm auxiliary line input jack. Operating at an input sensitivity of 250 mV, this connection accepts direct analog line-out audio signals from a wide variety of playback equipment, including:
- MP3 players and personal digital audio players
- CD players and portable disc drives
- DVD players and multimedia instructional units
- External audio playback devices with standard 3.5 mm line outputs
Audio signals introduced via the 3.5 mm line input or microphone socket are amplified through low-distortion internal circuitry delivering up to 12 W maximum power output directly across the integrated 4-ohm (4Ω) internal speaker transducer.
Electrical and Charging Infrastructure Compatibility
The Ahuja NBA-15 operates on an integrated internal 3.7 V, 2000 mAh rechargeable lithium-ion battery. Recharging is handled via the dedicated AC power adapter supplied for the system. The power supply supports worldwide commercial utility mains voltages, accommodating an AC input range of 100–240 V at 50/60 Hz and stepping down to deliver a regulated DC 5 V, 750 mA charging output directly to the unit. Operating status and recharge requirements are visually monitored via the amplifier's built-in low-battery LED indicator.
Interface and Electrical Specifications Matrix
| Interface / Subsystem | Connector / Mechanism | Sensitivity / Rating | Compatible Device / Destination |
|---|---|---|---|
| Microphone Input (Mic-1) | Ø 3.5 mm Socket | 1.0 mV | Cardioid condenser headband microphone |
| Auxiliary Line Input | Ø 3.5 mm Socket | 250 mV | DVD players, CD players, MP3 players, analog line-out devices |
| Internal Load | Internal Driver | 4 Ω Impedance | 12 W Max internal output circuitry (80–12,000 Hz) |
| Charging Input Interface | DC Charging Port | 5 V DC, 750 mA | 100–240 V AC, 50/60 Hz to 5 V DC, 750 mA adapter |
| Integrated Battery Storage | Internal Pack | 3.7 V, 2000 mAh | Internal rechargeable Lithium-ion cell assembly |
Mounting and Mechanical Interfacing
Weighing approximately 0.34 kg (340 g) with compact housing dimensions of 86 mm (W) × 98 mm (H) × 44 mm (D), the amplifier housing interfaces directly with wearable carrying accessories. It is mechanically compatible for deployment worn around the waist or slung across the shoulder using the included strap assembly, maintaining secure positioning during active movement in industrial walkthroughs, training seminars, and classroom environments.
