• Posts
  • RSS
  • ◂◂RSS
  • Contact

  • AudioBox vsl1818 Recording Clicks

    November 27th, 2012
    music, sound, tech, vsl1818  [html]
    A few weeks ago I wrote about my new audio interface. Since then I've used it to run sound at two dances, and it's done what I wanted it to. I've also tried to use it for recording, however, and am much less happy. I keep getting clicks in the recording. [1] For example:
    click1.wav
    Zooming in on the audio it looks like this:
    That's three tracks of audio and one track of nothing, showing a single sample out of place.

    I made some more samples:

    clicks-verylong.wav
    Looking at these I thought I saw a pattern: for a few samples in a row the sign is reversed. It's hard to be sure, though, with this setup. So I tried a higher pitch sine wave and put the mics at different distances so they'd have phase shifts relative to each other. Sure enough, some glitch is flipping the polarity:
    high.wav
    (On track 1 two samples are flipped while on tracks 2 and 3 three are. On all the others I looked at the same number of samples were off on every track.)

    What would do this? I don't know. I've posted on the presonus forum; we'll see what they say.


    [1] While I noticed them whatever I was doing, I decided to make a test setup so I could really see what was happening. I had my phone generate a sine wave and pointed three microphones at it. I restarted my computer (a mid 2011 13" macbook air on 10.8) so it would be fresh, started VSL (1.2.5296), started Audacity [2], and set it to record all 8 tracks.

    [2] I also got these clicks when using Presonus' Studio One, but I'm more familiar with Audacity so it was easier to take screenshots and make clips there.

    Comment via: google plus, facebook

    Recent posts on blogs I like:

    The Gift of It's Your Problem Now

    Recently a security hole in a certain open source Java library resulted in a worldwide emergency kerfuffle as, say, 40% of the possibly hundreds of millions of worldwide deployments of this library needed to be updated in a hurry. (The other 60% also …

    via apenwarr January 1, 2022

    The container throttling problem

    This is an excerpt from an internal document David Mackey and I co-authored in April 2019. The document is excerpted since much of the original doc was about comparing possible approaches to increasing efficency at Twitter, which is mostly information tha…

    via Posts on December 18, 2021

    Experiences in raising children in shared housing

    Sometimes I see posts about people’s hope to raise children in a group housing situation, and it often seems overly optimistic to me. In particular they seem to expect that there will be more shared childcare than I think should be expected. Today I talke…

    via The whole sky October 18, 2021

    more     (via openring)


  • Posts
  • RSS
  • ◂◂RSS
  • Contact