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Re: Phase offset for OscillatorNodes?

From: redman <redman@redman.demon.nl>
Date: Tue, 27 Nov 2012 00:29:24 +0100
Message-ID: <50B3FB54.4060204@redman.demon.nl>
To: public-audio@w3.org
On 26-Nov-12 21:27, Chris Rogers wrote:
> On Mon, Nov 26, 2012 at 2:43 AM, Jussi Kalliokoski<
> jussi.kalliokoski@gmail.com>  wrote:
>
>>
>> On Mon, Nov 26, 2012 at 6:32 AM, Chris Rogers<crogers@google.com>  wrote:
>>
>>>
>>> On Sat, Nov 24, 2012 at 7:01 AM, Patrick Borgeat<
>>> patrick.borgeat@gmail.com>  wrote:
>>>
>>>> Hi there,
>>>>
>>>> I wonder if OscillatorNodes could have some kind of phase offset (or
>>>> maybe I'm missing something and there is such thing?)
>>>>
>>>> Here's an example how the phase parameter in SuperCollider affects the
>>>> signal:
>>>>
>>>>
>>>> [image: Inline-Bild 3]
>>>> [image: Inline-Bild 4]
>>>>
>>>> Phase offsets are pretty important for LFOs. I also use them for drum
>>>> synthesis (to have a nice click at the beginning).
>>>>
>>>> A phase offset could be passed as an optional double offset=0 parameter
>>>> to the start method of OscillatorNodes. A modulateable phase parameter
>>>> could be interesting as well off course, but might be overkill for the Web
>>>> Audio API.
>>>>
>>>>
>>>> Looking forward reading your thoughts on that :-).
>>>>
>>> Hi Patrick, in addition to an optional argument as you suggest, we might
>>> consider a .phase attribute which is an AudioParam.  We can already get
>>> many FM effects since the .frequency attribute is pretty flexible.  But
>>> maybe .phase as an AudioParam would also be worthwhile.
>>>
>> Is that phase as in phase offset? Phase offset might be more useful, but
>> admittedly you might be able to create pretty interesting stuff with phase
>> modulation, although it sort of overlaps with the waveshaper node.
>>
> Yeah, .phaseOffset is really what it needs to be I think.  This would be
> additive with the cummulative phase from .frequency (and .detune).  This
> seems nice since if you set .frequency to 0, then there would be no
> cummulative phase and you could control the phase directly with
> .phaseOffset.  How does that sound?
>
Sounds like Yamaha!
:)

(i just assume everyone knows that the Yamaha implementation of FM (DX7 
etc.) was in fact phase modulation as described above).
Received on Monday, 26 November 2012 23:29:55 UTC

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