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Filter Description

poly-sinc-hb Linear-phase polyphase half-band filter with steep cut-off and high

attenuation.

sinc This is a special type of filter, slightly similar to FIR, but with a

possibility of asynchronous operation for conversions from any

rate to any other rate. Computationally heavy.

polynomial-1 Polynomial interpolation. Most natural polynomial interpolation for

audio. Only two samples of pre- and post-echo. Frequency

response rolls off slowly in the top octave. Poor stop-band

rejection and will thus leak fairly high amount of ultrasonic noise.

These type of filters are sometimes referred to as “non-ringing” by

some manufacturers. Not recommended.

polynomial-2 Similar to polynomial-1, but higher stop-band rejection with the

expense of being a bit less natural for audio. Not recommended.

minringFIR Minimum ringing FIR. Uses special algorithm to create a linear-

phase filter that minimizes amount of ringing while providing better

frequency-response and attenuation than polynomial interpolators.

Performance and ringing is between polynomial and poly-sinc-

short.

*-2s Two stage oversampling. First stage rate conversion is performed

by at least by factor of 8 using the selected algorithm, and further

converted to the final rate using “minringFIR” algorithm. This

lowers the overall CPU load, while preserving almost the same

conversion quality. Especially useful for highest output rates.

2.12. Noise-shaping / dither / modulator selection

This selection can be used to switch between different word-length reduction

algorithms. Especially important when playback hardware supports less than 24 bits.

This selection cannot be changed during playback.