Michael8it
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Why is my waveform lopsided ??
I am the recording engineer for my church. I have noticed that when I recorded our services, specifically the preaching, that the 'negative' side of the wave is always greater in amplitude that the 'positive' or upside of the wave by about 3DB. For instance, if my average peak on the top of the wave is -9db, the average peak on the downside is -6db.
I notice this because I always run a limiter first thing to lob off any stray spikes (a pop, cough, a bang on the pulpit, etc), but I always have to way the downside of the wave to set my limiter, not the upside. If I gauge by the upside of the wave I am chopping too much off the bottom.
Can someone explain why this is the case? Also - we use a pulpit mic and a wireless - it seems to be consistent with both.
Thank you,
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Jamz0r
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Re:Why is my waveform lopsided ??
2010/02/06 16:39:12
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I believe that is called DC offset. If your recording app doesn't have a DC offset correction feature in the "processing" menu, I've heard you can try applying a steep high pass filter to remove everything below 20 Hz to correct or at least reduce the problem. Forgot to add that the cause of this may be due to using analog gear on the way into you DAW...mixer, etc.
post edited by Jamz0r - 2010/02/06 16:41:08
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Guitarhacker
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Re:Why is my waveform lopsided ??
2010/02/06 17:31:35
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I have noticed this in many of my waves.... I can't seem to hear any issues, and we did have a discussion on this about a year ago...and DC offset was discussed.
So basically..... I ignore it.
My website & music: www.herbhartley.com MC4/5/6/X1e.c, on a Custom DAW Focusrite Firewire Saffire Interface BMI/NSAI "Just as the blade chooses the warrior, so too, the song chooses the writer "
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jimmyrage
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Re:Why is my waveform lopsided ??
2010/02/06 17:42:00
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There's a process under/ process / audio / remove DC offset that is supposed to take care of that. I think the only problem it causes is low gain but I've never had to deal with it.
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Michael8it
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Re:Why is my waveform lopsided ??
2010/02/06 17:43:31
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Thanks for the feedback. I can't say that it has caused any real issues for me I was just curious.
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Dave Modisette
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Re:Why is my waveform lopsided ??
2010/02/06 19:32:21
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Tell your pastor to preach toward the other side of the church. ;)
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MarlboroMan23
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Re:Why is my waveform lopsided ??
2010/02/06 20:17:37
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gamblerschoice
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Re:Why is my waveform lopsided ??
2010/02/07 00:11:41
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A properly centered waveform with silence at the 0 db mark but with uneven top/bottom peaks may indicate a phase problem.
If this wave form, silence centered on the 0 db mark, with uneven top/bottom peaks is created when mixing down a midi file to audio through a synth or sound font player (which I see often), how could it be a phase problem, and how would you correct it (and should you correct it)?
I see waves like this all the time, especially the sax sound fonts I have. There seems to be nothing wrong with them, I have no real problem getting an "authentic" sound, and there is no volume or gain problems, not that I can hear.
Not being a "wise guy", Marlboroman (great screen name), but asking a serious follow up question. Any additional thoughts?
Later
Albert
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The Maillard Reaction
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Re:Why is my waveform lopsided ??
2010/02/07 00:14:34
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DC offset is probably a minimal cause of what the OP is seeing.
Lopsided waveforms usually indicate a different combination of complex harmonics.
It's real common to see *lopsided* waveforms with distortion style guitars tracks.
I forget which causes what but its the even ordered and odd ordered harmonics.
best,
mike
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MarlboroMan23
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Re:Why is my waveform lopsided ??
2010/02/07 18:22:35
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gamblerschoice
Not being a "wise guy", Marlboroman (great screen name), but asking a serious follow up question. Any additional thoughts?
Later
Albert
I had just read, maybe here, that was a possible cause. mike_mccue's explanation makes total sense. Glad to hear it because I see those waveforms from time to time in my recordings and worry. btw I'm actually very anti-smoking; my smoking friends gave me that name.
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