[PD] get sinusoid from a sine and a cosine oscillator

[Charles Z Henry]

What you seem to be doing is creating a spectrum which has magnitude 1
everywhere, and the phase is varying at a constant rate vs frequency.  That
means it has a constant group delay.

So... my guess is that you'd get an impulse in each block, whose timing
depends on the rate of the phasor.  When you vary the phasor frequency, it
will coincide with the peak of the hann window at some point and be its
loudest.

Should be a periodic complex tone.  I don't understand your goal:  you've
got sinusoids in the patch... to generate sinusoids?

Chuck


On Wed, Jan 29, 2014 at 9:12 AM, Alexandros Drymonitis <adrcki at gmail.com>wrote:

> Say I have a full sine and a full cosine cycle stored in two tables. I'm
> trying the following to get a sinusoid from [rifft~] but it doesn't work.
>
> [phasor~]
> |
> [*~ sizeOfTable - 3]
> |
> [+~ 1]
> |\
> | \
> |  [tabread4~ sine]
> |   \
> [tabread4~ cosine]
> |      \
> [rifft~]
> |
> |    [tabreceive~ hann]
> |    |
> [*~ ]
> |
> [/~ 1536]
>
> I've set the block size to 1024 in this subpatch, and there's a hann
> window in the parent patch as well. The tables have three guard points,
> that's why I'm multiplying [phasor~] by the size of the table minus three
> and then add one.
> The output of this is a waveform with very low amplitude that kind of
> bounces up and down within a sine like mask. Don't know if I'm making my
> self clear. My main question is, how do you get a sinusoid out of a sine
> and a cosine? Also, what's wrong in my approach?
>
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