This should produce far better results given it works directly on the frequency
response magnitudes prior to phase reconstruction, as it doesn't deal with a
linear phase filter on a truncated time-domain response (with the result also
getting truncated in both direction).
The in-library on-load HRTF resampler still uses the linear filter due to its
relative performance and simplicity benefits. It's good enough as a backup,
though users with custom HRTFs would benefit from resampling when creating the
mhr (adjusting its window size as appropriate/desired).
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