kfr | Sample Rate Conversion , FIR/IIR/Biquad Filters

_{(PowerShell is nice and flexible - but only when you use it to invoke only PowerShell commands rather than running native executables. For example, to run a program in the current directory you need to prefix the program's name with ./ - ostensibly this is done for safety and I assume for similarity to Unix shells, but it's the first in a long list of gotchas for anyone wanting to use PowerShell for tasks that would be trivial in old-school batch files)}

Anyway, you need to use Invoke-Command or Start-Process.

I've changed your script from using a piped expression into an easier-to-digest loop (and invoking .NET's Path.ChangeExtension directly because PowerShell's built-in string match-and-replace syntax is too arcane for me):