Benchmark Media Systems, Inc.
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DAC1 THD+N vs. Jitter Amplitude and Jitter Frequency
The above graph shows the results from the most severe jitter test that we could create with an Audio Precision
System 2 Cascade test set. We selected a 10-kHz audio test tone in order to maximize the sensitivity of the test.
We set the interface jitter amplitude to its maximum value of 12.75 UI (2075 ns) of jitter. We then swept the jitter
frequency from 2 Hz to 9 kHz and plotted the THD+N from the DAC1. Absolutely no change in THD+N was
observed at any test frequency, and the DAC1 performance did not change when the jitter was turned off. The
same test was conducted using FFT analysis to look for jitter-induced artifacts. No change was observed on a
FFT analysis (see the next graph).
