One sided waveforms?

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One sided waveforms?

Post by Arpangel »

I’m regularly getting waveforms in Reaper that are constantly one sided, like I only see the lower part of a waveform, with little above that.
Is this something to do with DC offset issues? I seem to remember reading about this somewhere, but can’t remember.
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Re: One sided waveforms?

Post by Mike Stranks »

Music? Voice? If music which instrument(s)?

An image/screenshot would be useful...

Assymetric waveforms are not at all uncommon and usually nothing to do with DCO... there are regular discussions here - including just last week iirc.
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Re: One sided waveforms?

Post by Arpangel »

Mike Stranks wrote: Sun Dec 05, 2021 8:57 am Music? Voice? If music which instrument(s)?

An image/screenshot would be useful...

Assymetric waveforms are not at all uncommon and usually nothing to do with DCO... there are regular discussions here - including just last week iirc.

Anything, any sound, sometimes the waveform is entirely in the positive, or negative.
I’m wondering if there’s some sort of phase cancellation going on, somewhere in the signal chain?
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Re: One sided waveforms?

Post by ef37a »

MoooHASSIVE even harmonic distortion Tone!

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Re: One sided waveforms?

Post by Hugh Robjohns »

Arpangel wrote: Sun Dec 05, 2021 8:27 amI’m regularly getting waveforms in Reaper that are constantly one sided, like I only see the lower part of a waveform, with little above that.

There are lots of perfectly natural reasons why this can occur, and it's usually to do with the harmonic composition (and the phase relationships of those harmonics) within the signal.

Asymmetry is very common with voices, brass and simple synthesizer sounds, for example.

https://www.soundonsound.com/sound-advi ... lop-sided

Is this something to do with DC offset issues?

DC offset issues are extremely rare and the kind of fault condition today that could cause them would be evident in other, more obvious ways.

But if it was a DC offset you would see a decaying waveform settling away from the centre line, whereas an asymmetrical waveform will settle on the line.

My advice, stop looking at the pretty pictures and concentrate more on the lovely sounds....
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Re: One sided waveforms?

Post by Hugh Robjohns »

Arpangel wrote: Sun Dec 05, 2021 9:28 amI’m wondering if there’s some sort of phase cancellation going on, somewhere in the signal chain?

Some sort of weird phase cancellation that only removes negative half cycles? That's clever! :think::geek:
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Re: One sided waveforms?

Post by Arpangel »

Thanks folks, it’s mainly on accordion, if that helps?

:think:
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Re: One sided waveforms?

Post by ef37a »

Arpangel wrote: Sun Dec 05, 2021 12:46 pm Thanks folks, it’s mainly on accordion, if that helps?

:think:

Vivre la difference!

I agree with Hugh. 'Pictures' can be off putting and in any case the 'waveforms' you get in DAWs are not 'true' in the sense of that which an 'scope would display (and that would be different for various timebase and trigger/delay settings)

Sound 'pictures' have a place in the home studio but mainly as a diagnostic tool. When son was here making music he would 'experiment' with various gear lashups. Once a week or so I would run a Right Mark Anny test and almost always pickup hums above my -93dBFS baseline noise floor. Some re dressing of mains and audio cables usually restored quietitude.

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Re: One sided waveforms?

Post by Hugh Robjohns »

Arpangel wrote: Sun Dec 05, 2021 12:46 pm Thanks folks, it’s mainly on accordion, if that helps?

Think about how the accordion makes its sound, and how that might be conveyed in sound pressure variations....
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Re: One sided waveforms?

Post by blinddrew »

It's almost like physics or something.
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Re: One sided waveforms?

Post by Hugh Robjohns »

:ugeek::shh:

There is a difference between a sound engineer and a recording technician. One knows which buttons to press. The other knows what happens when the buttons are pressed! :lol:
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Re: One sided waveforms?

Post by Arpangel »

Hugh Robjohns wrote: Sun Dec 05, 2021 1:09 pm
Arpangel wrote: Sun Dec 05, 2021 12:46 pm Thanks folks, it’s mainly on accordion, if that helps?

Think about how the accordion makes its sound, and how that might be conveyed in sound pressure variations....

You have got a point there Hugh, my friend explained to me, his accordion has three reeds, which you can switch in and out, that produce different chorusing effects, which may have something to do with it.
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