Talk:DC offset

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Steve 06Nov12: Audio example that "defies" DC offset removal in the Normalize effect: trumpet-offset-example.flac.
The Nyquist DC offset tool using the default Dynamic bias correction handles this much better.


Gale 28Oct12: I think offset is much more common with built-in sound devices than USB devices. You could possibly have had the current full div about offset removal in Proposal DC Management then linked to it on the individual pages and so had shorter text on those. But I think it's reasonable now; more people will check it with the instructions in their face.

  • Peter 29Oct12: The problem with putting it on the Proposal page is that if and when the proposal got implemented the page could disappear. I did think for the Manual that a consolidated entry on the "Normalize" page would have been an approach - but I agree it's more "in your face" this way with fuller separate entries. Thoughts?
  • Gale 29Oct12: I'd like to see a DC offset page (analagous to Dither) created in the Digital Audio Technology Category containing the user-facing stuff moved out of Proposal DC Management. We could then link in the Manual to DC offset with more confidence, and so make the point that having hardware that does not have offset in the first place is still preferable. If you're happy, I'd say do it. If we did that, I would think Removing Artifacts could lose the div in favour of a link to DC offset.

    For the Manual, it would probably be OK to have the div only in the "Normalize" page if the text in the other pages where the div is now was expanded a little. For example, that text might be "If this is the case with your recordings, see the Normalize page for how to use Normalize to remove DC offset and how to check if your Windows sound device can perform this correction automatically."

    • Peter 30Oct12: Good idea Gale - so today a made a new Wiki page DC offset based on the material from Proposal DC Management as you suggested - but with a lot of tweaks (still draft though - I will advertise it on the Manual email list for "merciless editing"). Once it gets to an acceptable state I will fix the Wiki links/notes. I'm guessing that we can remove the advice & note from the top of Proposal DC Management as part of that?
      • Gale 30Oct12: And I think we can remove the stuff at the bottom too, which has been moved to DC offset. The huge image on the Proposal page doesn't add a great deal, unless we explicitly want to show a stereo track with matching offset in each channel? So I've wrapped the material to be removed from Proposal DC Management in ednotes and added links to this page and to DC offset if anyone needs to know what offset is/does.
        • Peter 31Oct12: Removed both lots of "stuff" from the DC removal proposal. An worked on the pages that had the notes divs on windows h/w DC offset removal. I think that's probably it for the Wiki on this topic for now?
          • Gale 31Oct12: Yes, except DC offset is still in flux at the moment as we have to thrash out how to handle the issue of asymmetrical waveforms.
    • Peter 30Oct12: Once that lot's finished I'll then turn my attention back to the related entries in the Manual. I assume that it will be ok to link from the Manual to Wiki DC offset?
      And thanks (to you and Ed - and now Steve too) for the "merciless editing".
      • Gale 30Oct12: In moderation, if at all. The Manual Normalize page didn't have any explanatory link to offset, so I gave it a link to the Manual Glossary entry for offset. The Glossary is probably the link you should use from the Manual, though since offset is an important topic for the Manual Normalize page, you could possibly say on that page to go to DC offset for more explanation.
        • Peter 31Oct12: I still think it's worth trimming the detailed Windows advice notes in the manual - I would suggest leaving a simpler note with a link from each note to DC offset here in the Wiki. That way we end up with only one place to maintain the detailed instructions. Thoughts?

          Should we also be adding a link to Wiki > DC offset from the Manual's Glossary entry on DC offset?

          • Gale 31Oct12: My idea (as stated above) is that we would only have the "Windows" div on the "Normalize" page in the Manual. The pages that have that div now should lose the div and could have text as follows with the internal Manual links shown: "If this is the case with your recordings, see the Normalize page for how to use Normalize to remove DC offset and how to check if your Windows sound device can perform this correction automatically."

            I'd prefer the Glossary did not have links to the main Wiki because of confusion with the links to Wikipedia. However I have added a link to DC offset on the Manual Normalize page, which makes it less verbose and means that Manual pages that now have the "Windows" div can link indirectly to DC offset that way.

            • Peter 1Nov12: OK I implemented your idea as above. I also added an additional "Tip" to the Manual's Normalize page advising "do DC removal early and amplitude adjustment late".