Mechanical Placement and Rack Integration
The Hitune Bass HSSA-350 public address mixing amplifier is engineered inside a heavy-duty black metal enclosure chassis measuring 480 mm in width, 160 mm in height, and 360 mm in depth. With a net weight of 21.3 kg, the unit requires a rigid, level surface or a standard reinforced equipment rack shelf capable of bearing sustained mechanical loads. When positioning the chassis, maintain adequate clearance around the enclosure to ensure uninterrupted thermal dissipation, keeping the surrounding airflow unobstructed during high-power sound delivery.
Primary AC Mains and 36V DC Power Hookup
The HSSA-350 features a versatile dual-power operating architecture. The amplifier connects directly to standard AC mains for routine facility operations while providing dedicated rear DC terminal blocks for connection to an external 36V DC power system or battery bank (they are not included). This dual-supply configuration allows uninterrupted emergency operation with instant transfer to DC battery power (they are not included) in the event of an AC supply failure.
- AC Mains Connection: Connect the integrated AC mains cord to a grounded power receptacle. Ensure line voltage stability prior to switching on the front-panel power.
- 36V DC Auxiliary Hookup: Wire the DC terminals to a matching 36V DC external battery source (they are not included). Observe strict polarity markings (positive to positive, negative to negative) to prevent reverse-polarity damage.
- Instantaneous Fallback: When both AC and 36V DC lines are connected, the amplifier automatically operates from AC mains and switches over instantaneously to 36V DC operation if AC drops.
Speaker Output Wiring & Load Termination
The rear output panel supports both low-impedance box configurations and high-voltage distributed line arrays. Wire the speaker network to either low-impedance or high-impedance taps based on your architectural zoning; never connect low-impedance and constant-voltage loads simultaneously to the same terminal group.
| Terminal Configuration | Output Rating | Recommended Load Matching |
|---|---|---|
| Low-Impedance (4Ω, 8Ω) | 350W RMS (450W Max) | Cabinet box speakers wired to present an aggregate impedance load of 4Ω or 8Ω without dipping below terminal ratings. |
| High-Impedance (70V Line) | 350W RMS (450W Max) | Distributed ceiling, column, or horn speakers fitted with 70V line matching transformers (LMT), total wattage capped under 350W. |
| High-Impedance (100V Line) | 350W RMS (450W Max) | Distributed multi-speaker runs equipped with 100V line transformers; sum of all transformer primary taps must not exceed 350W RMS. |
Acoustic Load Selector Configuration
Before driving acoustic loads, configure the dedicated Box Speaker / Driver Unit selector switch located on the chassis. Setting this switch to the 'Driver Unit' position defeats the internal bass boost circuitry. This safeguard attenuates excessive low-frequency signals that could mechanically damage horn driver diaphragms, tailoring output frequencies within the 50 Hz to 15,000 Hz (±3dB) response window for vocal clarity. Set the selector switch to 'Box Speaker' when driving full-range cabinet speakers to restore full low-end response, which can be further adjusted via the Bass control (±10dB at 100Hz) and Treble control (±10dB at 10kHz).
Input Channel Termination & Booster Amplifier Setup
The mixing amplifier provides comprehensive input interfacing for multi-channel audio setups:
- Microphone Channels (1 to 7): Connect dynamic microphones to the 7 dedicated mic inputs, each calibrated to a sensitivity of 0.8mV at 4.7kΩ input impedance.
- Auxiliary Channels (Aux 1 & Aux 2): Interconnect line-level media players or source equipment using Aux 1 (rated at 200mV / 470kΩ) or Aux 2 (rated at 100mV / 470kΩ).
- Line Input for Booster Operation: The dedicated Line Input (1V / 50kΩ) accepts balanced or unbalanced line-level signals directly from the output of an external audio mixing console. This enables the HSSA-350 to function as a standalone booster power amplifier for expansive industrial paging and auditorium systems.
Overload and Fault Reset Protocol
The unit incorporates an integrated resettable circuit breaker engineered to protect internal output circuitry against dead shorts on speaker lines and prolonged thermal or electrical overloads beyond 350W RMS. If the amplifier cuts output unexpectedly, turn off the power switch, isolate the speaker field wiring to rectify any line shorts or impedance mismatches, and firmly depress the rear-mounted circuit breaker button to reset the system before restoring operation.
