Professional Audio & Video Solutions

AUX-0040 Switching Amplifier Measurement Filter

AUX-0040 Switching Amplifier Measurement Filter

AUX-0040 Switching Amplifier Measurement Filter is a passive two-channel 40 kHz low-pass filter.

For some initial context, we’ll begin with a relevant quote from Bruce Hofer’s white paper Measuring Switch-Mode Power Amplifiers:

“Measuring the performance of switch-mode amplifiers presents some…unique challenges. They inherently generate ultra-sonic artifacts and spurious signals with slew rates that can provoke non-linear behavior within the input stages of high quality audio test and measurement equipment.
Absolutely worthless and inaccurate results can result unless effective measures are taken to prevent this non-linear behavior.”

In all likelihood, this is nothing new to any of you, as it was the genesis of both the AUX-0025 and the AUX-0100. However, what will be new to you is the imminent arrival of the latest addition to AP’s AUX family, the AUX-0040 Switching Amplifier Measurement Filter.

Where the AUX-0040 differs from the -0025 and/or -0100 is in its frequency range, with twice the bandwidth of those 20 kHz filters. Specifically, the AUX-0040 is a passive two-channel 40 kHz low-pass filter designed to connect to high-impedance audio analyzer inputs (and thus allows testing of switch-mode amplifier performance up to 40 kHz).

    Main Advantages

  • As an Standard
  • Produced by Audio Precision

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