Question about the shape of my Recording

If the waveform settles at the centre zero line, it’s asymmetric. If the waveform centre is above or below then it’s DC offset.

Looking at the OP’s waveforms it seems to be typical asymmetry.

From that SOS article -

In contrast, natural waveform asymmetry cannot be ‘corrected’ with a high-pass filter, and a rather more complicated solution is required called a ‘phase rotator’. Generally, there is no need to ‘correct’ a naturally asymmetrical signal, but occasionally the asymmetry can restrict how much the signal can be amplified because the stronger half of the waveform will reach the clip level before the weaker side. By using a phase rotator process to alter the harmonic phase relationships, a more balanced symmetry can be established, allowing slightly more gain to be applied before both sides reach the clipping level at the same amplitude. Asymmetrical waveforms can also sometimes confuse the side-chain level-detection circuitry (or algorithms) of some compressors, resulting in less effective compression than might be expected.

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What I see is some synth voice in the beginning that seems to be perfectly centered. Then something bassy comes in, and even in the recording without the EHX thingy it’s already looking asymmetric (not offset).
Even with the waveform zoomed out that much and the small resolution, in the upper screenshot it’s visibile that the upper half has less amplitude variation than the flappy looking lower half.

@Tchu if you try the suggested corrections for DC Offset in the DAW and look if that changes anything significant, then … :wink:

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It’s a phase issue.

I can run it through RX for you if you want me to fix it

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Is there any way to explain the reason the pedal has caused the issue, or correct it at the source? I don’t doubt that this information is correct, but I’d like to know in case something similar ever happens to me.

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I’m pretty sure I get that asymmetrical shape on some of the digital tracks of the Syntakt when recording via Overbridge, so in theory a fully digital signal chain. Not a constant offset, but that asymmetrical/lopsided waveform. What’s the reason for that?

I’ll have to check that next time I start the daw, thanks.

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Lots of things can cause asymmetric waveforms, both analog and digital, but in this case with the platform pedal I would assume it’s either the power supply or an out of spec op amp. I think very fast attack and release times can also cause these issues.

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I kind of hope we get a resolved stamp on this one, I think it’s interesting finding cause and effect for this type of issue. I mean it’s not interesting for @Tchu who has to deal with it, but it will probably feel good if he can discover the source. Much more difficult to do if it’s an opamp though.

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Don’t worry, I like these kind of technical discussions.

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Just had this on the screen, one of the Syntakt analog voices.

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Anyone know of an app or process to even up a lopsided recording in iOS?

The phenomenon itself doesn’t bother me - just want to get a bit more volume when I normalize!

Can you cut off low frequencies ? Sub-audio, say a high pass set to 20Hz or something ?

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Interesting. These remind me of Serge waveforms, only in Serge systems you’re often entirely above 0 volts / db . The reason is you tend to use envelope generator type things as oscillators.

I don’t think it’s a problem, unless you’re trying to win a loudness war.

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I also noticed assymetric waveforms coming out of my Digitakt, when using sinlge cycles, I would love to know the reason myself, I guess it is caused by the phase of the filter resonance.

The thing that “solved” my issue with the assymetry of the waveform was turning the resonance way down on the filter, which ended up sounding unpleasent for me. :smiley:

But at least I can look at my beautiful waveforms now totally symmetric, carressing my OCD

I get lots of DC offset too when abusing rytm compressor and master distortion, especially if I set some bias (symmetry), on my limiter Pro L2 there’s a DC offset switch too but it’s described as “gentle DC offset filter”, so I was wondering if all DC offset are the same? i.e. Utility vs Pro L2?