The QUEST PB-4120D 4-channel commercial power amplifier is specifically designed to deliver optimal efficiency without compromising sound quality. A true concentration of technology, this Class D amplifier meets the demands of audio professionals thanks to its flexibility and performance.
Each channel of this Calss D 70V power amplifier can be independently configured to operate in low impedance (4/8 ohms) or 70/100V line mode, allowing mixed use within the same audio system.
Whether powering low-impedance loudspeakers directly or a long-distance distributed audio network, it adapts to all scenarios. With an output power of 120 watts RMS per channel, this commercial 70V amplifier ensures clear and dynamic sound reproduction while maintaining controlled energy consumption through advanced digital technology.
Ideal for distributed audio installations in commercial, educational, or institutional environments, this power amplifier stands out with its transformerless design, integrated protection circuits, and per-channel LED indicators for simple, reliable, and safe operation.
By choosing this QUEST commercial 70V amplifier, you are opting for a robust, versatile, and lightweight solution designed to meet the long-term demands of the most complex professional audio installations.
Features:
Delivers 120W of clean power per channel, compatible with 70/100V and 4-ohm loads
Class D amplifier with high 85% efficiency, powered by an advanced switching power supply
Optimized design minimizes heat generation through low power consumption
Built-in output transformers for 70/100V systems ensure constant voltage distribution with a frequency response of 40 Hz to 20 kHz
Independent input level controls per channel for precise and customized adjustment
Per-channel LED indicators provide real-time feedback on signal presence, output level, and clip detection
Forced-air cooling system ensures stable performance and protection against overheating
Euroblock input connectors are compatible with both balanced and unbalanced signals
Euroblock output connectors support cable sizes up to 12 AWG
Housed in a 19-inch, dual-rack-space (2RU) rack-mount enclosure
Specifications:
Rated Output Power: 120 W x 4 (70/100 V); 60 W x 4 (8 ohms); 120 W x 4 (4 ohms)
Frequency Response: 50 Hz – 18 kHz
Total Harmonic Distortion + Noise (THD+N): < 0.3%
Signal-to-Noise Ratio (SNR): > 90 dB
Crosstalk: > 70 dB
Amplification Technology: Class D
Input Impedance: 10 kO balanced
Input Sensitivity: 1 Vrms
High-Pass Filter: 400 Hz
Power supply: 120 V AC, 50/60 Hz
Cooling System: Thermostatically controlled fan
CSA and cUL certified
