The Ahuja SSB-45EM 45W medium-wattage Public Address mixer amplifier is engineered for versatile integration across commercial, institutional, and industrial audio architectures. Its dual-impedance speaker outputs, standardized line-level routing, and multi-source input stages enable seamless pairing with both legacy PA equipment and modern sound reinforcement hardware.
Loudspeaker Load and Distribution Network Compatibility
The amplifier is equipped with versatile terminal taps on the rear panel to support two distinct loudspeaker wiring topologies: direct low-impedance speaker loads and high-impedance constant-voltage distributed lines.
- Low-Impedance Direct Drive (4Ω, 8Ω, 16Ω): Accommodates standard 4-ohm, 8-ohm, and 16-ohm loudspeaker configurations without requiring intermediate transformers. Ideal for short-run installations such as local paging horns, monitoring boxes, or small room acoustic clusters.
- High-Impedance Constant-Voltage Line (100V): Designed for multi-speaker distributed public address networks across large facilities, school campuses, or commercial corridors. Operates directly with ceiling speakers, sound columns, and horn speakers equipped with 100V Line Matching Transformers (LMT).
- Load Regulation: Delivers tight output voltage regulation of ≤ 2 dB from no load to full load at 1kHz, maintaining consistent audio levels across variable speaker tap loads up to the 45W RMS rated threshold (64W Max, 40W RMS at 5% THD, 30W RMS at 2% THD).
Audio Input Source Interfacing
The SSB-45EM features four dedicated audio input channels tailored for speech reinforcement and line-level background music playback:
- Microphone Inputs (Mic 1, Mic 2, Mic 3): Three discrete microphone channels rated at 0.65mV sensitivity with a 4.7kΩ input impedance. Optimized for dynamic low-impedance microphones, including manufacturer-recommended models such as the Ahuja ASM-580XLR, AUD-101, and AUD-77DX, to mitigate howling and feedback during high-gain operations.
- Auxiliary Input (Aux 1): One auxiliary channel rated at 100mV sensitivity and 470kΩ input impedance. Compatible with standard unbalanced line-level playback devices, including media players, CD players, desktop or laptop audio outputs, digital tone generators, and pre-mixer program feeds.
System Expansion, Booster Chaining, and Recording Compatibility
For installations requiring sound coverage beyond the onboard 45W power capacity, the unit includes an integrated preamplifier output rated at 200mV into a 600Ω load. This line-level output allows direct, low-distortion daisy-chaining into high-wattage power booster amplifiers or audio distribution matrices without requiring external attenuation. Additionally, the 200mV / 600Ω terminal can be interfaced directly with recording consoles, logging devices, or archiving systems to capture announcements and live proceedings simultaneously.
Power Supply and Redundancy Integration
Designed for mission-critical industrial paging and public notification reliability, the amplifier incorporates flexible dual-power operation:
- AC Mains Operation: Operates on standard AC 220–240V single-phase supplies at 50/60Hz, with an operational consumption rating of 110VA.
- DC Emergency Power: Accepts an external 12V DC battery (they are not included) via dedicated rear screw terminals, consuming 2A during direct current operation.
- Automatic Failover: Features automatic instant transfer switching to the 12V DC battery supply (they are not included) if AC mains power is interrupted, ensuring uninterrupted broadcast availability for emergency announcements.
