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Old 03.06.2014, 03:35 PM
Spreader Spreader is offline
Definately caught something...
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Join Date: 18.12.2012
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Quote:
Originally Posted by TweakHead View Post
I was going to take it easy, but no.

For the sake of truth: that's a pure 30.5Hz wave, it's got more then one complete cycle, in fact there's 30 and a half. The only thing you can complain about is "discontinuity" - so go ahead and search for that.
And how do you fit more than one complete cycle in the one second window? You can't. It's not a sine wave. Easier way to think about this is trying to fit a 0.5hz sine into the window. Now it's obvious that you have a rectified sine wave on your hands, which has entirely different spectrum than a sine wave.


Quote:
Originally Posted by TweakHead View Post
]
Further more: we can ear sine waves and sine waves don't actually produce any sort of clip in their beginning, not unless reproduction of the audio starts or ends on a non zero crossing point. You may have that "feeling" with instruments whose oscillators are incapable of fixing phase start position. You can set phase initial position on the Virus, btw.
This is incorrect. We cannot hear a real sine wave (just try it by setting the osc to 0 phase- you will hear the click and can even EQ it). A real sine wave would have to be infinite. When you play a shorter than that sine wave it's combined with the gate(silence) at the start. This kind of function will have to have a different spectrum than a pure sine wave and it will contain (almost) all frequencies - some of which are cut off by the converter's reconstruction filter altering the sine wave. A perfectly round finite sine wave can't even be reproduced...

Quote:
Originally Posted by TweakHead View Post
]
The only thing wrong with my sample is that you can't loop it and still get a perfect 30.5Hz sine wave, you'd have to go back, choose a zero cross point at the end of a cycle, and then if you were to loop that, you'd have a perfect 30.5Hz sine wave playing for as long as it makes you happy. Sampling frequency (the time you set to analyse a signal) has nothing to do with the frequency of the signal itself, so as a matter of fact you are INDEED confusing a lot of things. Mentioning spectral leakage is almost laughable at this point, since you show absolutely no accuracy in your remarks and you're failing to provide a solid basis for any of your claims. In fact, it all reads like pretentious rubbish talk to me and any informed reader. So there's a little honesty for you to digest slowly with a pinch of salt m8.
If you loop a 30.5hz sine that is cut off at 1 second mark, you would hear exactly what I have stated - the spectrum would contain more than one frequency and the frequency of the wave would be some multiple of the 1hz. 30.5hz would be obviously impossible inside a 1 second window. Although our hearing works very differently from a spectrum analyzer so using a much smaller window works much better - try 0.01sec. The point that you can slice a wave and loop it past the window has nothing to do with any of this.

Last edited by Spreader : 03.06.2014 at 04:50 PM.
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