[PD] [sqosc~]-issues

Martin Peach martin.peach at sympatico.ca
Mon Mar 26 16:44:38 CEST 2007

Roman Haefeli wrote:
> there is somethings else, i forgoto mention: when playing [sqosc~] with
> low frequencies (<100Hz), it sounds a bit dull compared to a raw square
> with the same amplitude and the same frequency. does [sqosc~] not play
> the full spectrum in the low area?
There are two things: first the sqosc~ wave is not as loud as osc~ or a 
raw square: you need to multiply it by 1.333 to get -1 to +1.
Second, the wave is always bandlimited. If you think about it, a raw 
square wave has components at the highest frequency at the transitions, 
so you always get aliasing effects, even at low frequencies.
In effect the transition usually happens at the wrong time at low 
frequencies, so there is a kind of jitter introduced, which can be 
noticeable if the wave is near a subharmonic of the sampling frequency.
[sqosc~] is slew-rate limited so the transitions always happen at the 
right time, but they are smeared out a bit.


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