4 Channel Class D Power Amplifier
The Quest Commercial PB-4120D and PB-4300D are versatile and efficient Class D, digital multi-channel
power amplifiers of advanced design, able to drive 70/100 V-line loudspeaker systems directly as well
as low impedance 4/8ohms speaker loads. The PB-4120D can deliver 120 watts RMS per channel, and
the PB-4300D can deliver 300 watts RMS per channel. The PB-Series advanced technology, clear sound,
lightweight and reliable performance makes it ideal for any distributed sound system installation.

KEY SPECIFICATIONS
• Four channel power amp system – 120W or
 300W RMS per channel.
• Class D transformerless design.
• Low-Z (4 or 8 Ω) or Hi-Z (70V or100V) output.
• Fully independent channels, allow some to be
 used in Low-Z while others can be used in
 Hi-Z simultaneously.
• Front-panel LED indicators per channel: signal,
 clip, and protect.

• Input connectors: balanced three-pin Phoenix.
• Output connectors: two-pin Phoenix.
• Protections: Output current limiting, thermal
 protection & fuse.
• Switch-mode universal power supply.
• Front-to-back cooling.
• 2U rack space height