Greetings All

I plan on adding a phase shift to a signal/a wave file I import which is easy enough mathematically
example: if the signal is x=sin(2*pi*1*t) 
to do a phase shift I would just multiply x*e(-i*pi) which would phase shift the signal by 90 degrees.

But how does one multiple signals by complex numbers in PD like -i?

note: there will be a several different phase shifts so a simple hibert transform won't work in this instance 
thanks
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