QI 125.4
The QI 125.4 is a compact four-channel installation amplifier that forms the foundation of QUAD Industrial fixed audio systems. Purpose-designed for professional installations, QI 125.4 combines a small physical footprint with the flexibility and control required for modern commercial environments.
Housed in a slim half-rack, 1U chassis, QI 125.4 is easy to deploy in equipment racks, cupboards, under desks or wall-mounted locations where space is limited. It delivers exceptional versatility, offering four channels of low-impedance output or two high-impedance 70 V / 100 V outputs, allowing a single amplifier to support both Lo-Z and Hi-Z loudspeaker systems.
Automatic power sharing intelligently reallocates available power between channel pairs, ensuring consistent headroom and reliable performance as programme demands change across zones. This makes QI 125.4 ideally suited to retail, hospitality, corporate and leisure installations.
At the heart of the platform is QI CORE, our browser-based control software. Through a clear, installer-friendly interface, users can configure inputs, zones, DSP, routing and power management quickly and efficiently. The amplifier also includes internal speaker presets for all our loudspeakers, enabling faster commissioning and predictable, optimised system performance.
Compact, versatile and software-driven, QI 125.4 defines the core building block of QUAD Industrial fixed installation systems.
| Specification | Value |
|---|---|
| Channels | 4 Lo-Z / 2 Hi-Z |
| Topology | Class D |
| Output power @ 4Ω/8Ω/70V/100V* All channels driven | 125W Lo-Z / 250W Hi-Z |
| Output power @ 4Ω/8Ω/70V/100V* Single channel driven | 250W** |
| Output Power @ 16Ω*** All channels driven | 125W |
| Output Voltage | 70Vp / 140Vpp (unloaded) // Bridged 140Vp / 280 Vpp (unloaded) |
| Signal To Noise-Ratio | >106dB (A-weighted, 20Hz-20kHz, 8Ω load) |
| THD+N (typical) | < 0.05% (20Hz-20kHz, 8Ω load, 3dB below rated power) |
| Frequency Response | 20Hz-20kHz (+0/-0.25dB (8Ω load, 3dB below rated power) |
| Operating Temperature | 0-40C |
| Operating Voltage/Frequency | Universal Mains, 100V-240V, 50Hz-60Hz |
| Protection Cicuits | Short circuit -, DC -, Undervoltage -, Temperature - and Overload protection |
| Power Ratings | 1% THD @ 120Vac and 230Vac |
| Power Consumption | 150W |
| Power Supply | UREC™ universal mains switch mode power supply with Power Factor Correction (PFC) and standbyconverter |
| Included Accessory | AC cable, input connector x 2, GPIO socket connector, output connector, adhesive rubber feet x 4, document pack |
| Notes | *100V line mode operates at 90V (~-1dB) // ** Power sharing operational // *** 16Ω power output is limited by maximum voltage swing available in Lo-Z mode |
| Unpacked - Height (mm) | 44.5 |
| Unpacked - Width (mm) | 220 |
| Unpacked - Depth (mm) | 296 |
| Packed - Height (mm) | 90 |
| Packed - Width (mm) | 290 |
| Packed - Depth (mm) | 490 |
| Weight - Nett (kg) | 1.92 |
| Weight - Gross (kg) | 2.7 |
| Specification | QI 125.4 |
|---|---|
| Channels | 4 Lo-Z / 2 Hi-Z |
| Topology | Class D |
| Output power @ 4Ω/8Ω/70V/100V* All channels driven | 125W Lo-Z / 250W Hi-Z |
| Output power @ 4Ω/8Ω/70V/100V* Single channel driven | 250W** |
| Output Power @ 16Ω*** All channels driven | 125W |
| Output Voltage | 70Vp / 140Vpp (unloaded) // Bridged 140Vp / 280 Vpp (unloaded) |
| Signal To Noise-Ratio | >106dB (A-weighted, 20Hz-20kHz, 8Ω load) dB |
| THD+N (typical) | < 0.05% (20Hz-20kHz, 8Ω load, 3dB below rated power) |
| Frequency Response | 20Hz-20kHz (+0/-0.25dB (8Ω load, 3dB below rated power) |
| Operating Temperature | 0-40C |
| Operating Voltage/Frequency | Universal Mains, 100V-240V, 50Hz-60Hz |
| Protection Cicuits | Short circuit -, DC -, Undervoltage -, Temperature - and Overload protection |
| Power Ratings | 1% THD @ 120Vac and 230Vac |
| Power Consumption | 150W |
| Power Supply | UREC™ universal mains switch mode power supply with Power Factor Correction (PFC) and standbyconverter |
| Included Accessory | AC cable, input connector x 2, GPIO socket connector, output connector, adhesive rubber feet x 4, document pack |
| Notes | *100V line mode operates at 90V (~-1dB) // ** Power sharing operational // *** 16Ω power output is limited by maximum voltage swing available in Lo-Z mode |
| Unpacked - Height (mm) | 44.5 |
| Unpacked - Width (mm) | 220 |
| Unpacked - Depth (mm) | 296 |
| Packed - Height (mm) | 90 |
| Packed - Width (mm) | 290 |
| Packed - Depth (mm) | 490 |
| Weight - Nett (kg) | 1.92 |
| Weight - Gross (kg) | 2.7 |
