January 26, 2026
WHAT ABOUT THE LONG-TERM OUTPUT POWER OF THE AMPLIFIER?
Like most audio equipment, power amplifiers have many specifications that help us understand the performance and reliability of an amplifier. Most manufacturers, including QSC, specify both the maximum power (also referred to as “instantaneous” or “burst”) and the continuous power of their amplifiers.
Although no amplifier can sustain this output power for an extended period, the “max. power” provides a good indication of how an amplifier performs during temporary peaks.
The graph below shows the performance of the QSC CX-Q Series CX-Q 4K8 and CX-Q 8K8 amplifiers in a long-duration continuous power test conducted by QSC. Only the first 17 minutes of the test are shown, as the amplifiers reach thermal equilibrium within that time and nothing substantial changes thereafter.
Both amplifiers drive high-impedance loads at 100V and draw 600W per channel (CX-Q 8K8) and 300W per channel (CX-Q 4K8). All channels are loaded and driven using sine waves. During the first ten seconds, there is a gradual limitation of the output power as the amplifier warms up. More aggressive protection occurs between 10 and 100 seconds as the amplifier approaches the maximum allowable operating temperature.
After this point, the amplifier's output power and operating temperature stabilize at a level that is both safe and sustainable. During this test, no channel showed signs of distress, such as excessive distortion, shutdown, or failure to reproduce the audio signal.
While many amplifiers simply shut down during continuous high current consumption, the CX-Q series amplifiers will appropriately limit their output power to safe levels under the same conditions while producing uninterrupted audio.