[SoX-users] sinc/bandreject questions

[forget c. <for...@gm...>]

I'm confused by the results of the sinc command. For example, when trying
to implement a bandreject effect:

  play -n synth 3 sine 500 sinc 600-400

I hear a tone. But if I use bandreject directly:

  play -n synth 3 sine 500 bandreject 500 100

I hear nothing (except the attack). Why isn't sinc working?

Thanks!