About clipping

Discussion in 'Read Me' started by yek, Feb 8, 2012.

  1. atyourlasthourrr

    atyourlasthourrr
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    I'm referring to output clipping.
     
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  2. Rex

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    The output clip LED comes on 1 or 2 dB before actual clipping. If it's just flickering, you might not hear the added distortion. If it's on solid, you'll almost certainly hear it.
     
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  3. jimmynorrisjr

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    Or you can get something that manages multiple guitar outputs. An amp would handle it the same as the axe, if you set it like yes says. This is probably not only the easiest way, but also maybe the more authentic way. Just my 2 cents.
     
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  4. Mrcdboston

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    I notice clipping on the ax8

    What should the output be set on
     
  5. Rex

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    Is the clip light coming on?
     
  6. Mrcdboston

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    I'm so new to it - its when I turn the last Amp level knob up
     
  7. Rex

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    Yeah, you're probably clipping the output. There's a Main Out Clip light. Check and see whether it lights up red when you hear the clipping.

    Definitely turn that last Level knob down until the clipping goes away. If you need more volume, use the Out1 Level knob directly below it.
     
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  8. Mrcdboston

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    Thanks friend :)
     
  9. Rex

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    No problem. Did you get 'er solved?
     
  10. Mrcdboston

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    Yes I just dialed her back :) thanks mate
     
  11. kgk

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    There is something very fundamental that I don't understand here, the meaning of the "clipping" light.

    The A/D converter measures my guitar's voltage 44.1k times per second (?), and represents it as a number for the DSP algorithms to use. Is the problem that voltage on my guitar is outside the range of the A/D's ability to represent a number, so it saturates at its maximum (or minimum) possible reading?

    So, does "clipping" mean "the ADC has saturated?" If not, what does it actually mean?
     
  12. Rex

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    The Clip light lives at the other end of the signal chain—at the output. It means you're overdriving the D/A converter, not the A/D converter. So you fix it by reducing the internal digital signal level.
     
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  13. kgk

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    So "CLIP 1 OUT" means "DAC for output #1 Saturated," and "CLIP 2 OUT" means "DAC for output #2 Saturated." Yay, now I know, thanks!!!

    And how do I know that the ADC has saturated on the input side?
     
  14. kgk

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    I don't know how they manage the details, but the D/A converters likely saturate, meaning that your output cannot go above a certain maximum voltage, or below a certain minimum voltage. So, if you just clip a little bit, you won't be able to hear any difference, because the clipped signal will look almost identical to the ideal signal (its top and/or bottom will get a little trim). But as the clipping becomes more extreme, eventually it can turn your signal into square waves, and those will sound very different than one would like, and that's a definite problem.
     
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  15. Rex

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    Watch the IN1 and IN2 lights. The top red LED starts to glow a few dB before clipping. The INSTR input has a soft limiter that's pretty forgiving. You have to nail it pretty hard to hear audible artifacts.
     
  16. Timo

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    How much is this in LUFS? Or how do you measure the output volume - is there a standard you use?
     
  17. Rex

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    99 LUFSballons. :)

    The maximum input and output signal levels are specified in the manual.
     
  18. Timo

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    I can not find the information in the manual. I, at least, can not make measurement incorporating perception with the "The red LED lights at -6 dB" - the programming I do without proper measurement tools is always louder than the presets. Without ever touching the red light. The volume is all around.
    So how do you do it? Do you just flip between programs and do it by ear?
     
  19. Rex

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    Proper measurement tools are already built in. Use the VU meters. Shoot for 0 dB on the meters. That'll get you in the ballpark, with 20 dB of headroom to spare.

    Make your final adjustments by ear—just like all other gear. :)
     
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  20. Rex

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    No you didn't. What are you up to?
     

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