Bug Chorus and Random LFO

Discussion in 'AX8 Wishes + Bugs' started by DLC86, Apr 19, 2017 at 8:19 AM.

  1. #1 DLC86, Apr 19, 2017 at 8:19 AM
    Last edited: Apr 20, 2017 at 4:43 AM
    DLC86

    DLC86
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    I recently switched from the axe fx to the ax8 and noticed that one of my presets is acting weird and makes strange noises whenever I turn on the chorus block and it seems it's not cpu related. Tried a few different settings and narrowed it down to the selection of the random waveform in the chorus block LFO as the cause. If I turn auto depth off it gets a bit better but still weird.
    Hear for yourself, first part is the flanger block with te same settings (just to show how it's supposed to sound and how it sounded in my axe fx), second part is chorus block with auto depth set to low, third part chorus with auto depth off.



    Here's the preset too, even though I tried the same settings on other presets getting the same results.
     

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  2. lwknives

    lwknives
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    I would think that would be the expected result if you used a random LFO. According to the manual the random LFO is a square wave with random depth so your pitch will just jump around to random pitches instead of sweeping between them.
     
  3. DLC86

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    I think you haven't listened to the whole sample, that's what happens in the first part and it's ok.
    In the second part (from 0:36) you hear those scrachty sounds similar to digital clipping or to the ones you hear when approaching cpu limit, that's not normal at all and didn't happen in my old axe fx.
     
  4. lwknives

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    I did listen to the whole thing. I was thinking maybe that was just the sound of a sudden pitch shift that jumped supper fast. Is the first recording from the axe FX II? Does the first recording use a random LFO to change pitch? Did you use a random LFO in the FX II?
     
  5. DLC86

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    All answers in the first post ;)
     
  6. unix-guy

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    I've got no answer, but I'm going to test out your preset because since I like how it sounds (the correct part!).
     
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  7. lwknives

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    Are you sure that with your Axe FX II you weren't using a random LFO controller attached to the choruses LFO 1 depth?
    With the chorus set up like you are describing it should act like a pitch shifter that shifts the pitch in a random fashion.
    If you set the LFO to square wave does it do the same thing but not random?
     
  8. #8 DLC86, Apr 20, 2017 at 1:51 PM
    Last edited: Apr 20, 2017 at 1:57 PM
    DLC86

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    I transferred all my patches with fractool and checked for all the errors in the conversion before selling my axe fx, so pretty sure it's exactly the same.
    If I change waveform to anything else it won't do the same thing.
    Using random LFO in other blocks doesn't do the same thing. Setting up the flanger block to match the chorus (first part of my sample) it doesn't neither.
    I think it's pretty clear that it's not the pitch going up and down but a "digital fart", the same type you get sometimes when approaching 90% cpu or when you clip the output. The problem is to understand what's causing it, maybe a bug that causes a cpu spike? That will be a task for the engineers though
     
  9. lwknives

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    What are you attaching the LFO to in the flanger?
    Just to double check did you try a square wave in the chorus LFO?
     
  10. GiRa

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    What happens to the CPU while you are playing and running the random chorus?
     
  11. #11 DLC86, Apr 21, 2017 at 4:00 AM
    Last edited: Apr 21, 2017 at 4:24 AM
    DLC86

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    Nothing apparently, while playing it increases by 1-2% as usual.
    I tried some other configurations and found out that the farty sound follows the balance setting of the chorus block, and if I place the chorus before the amp its timbre changes being distorted/filtered by the amp and cab. In other words it's coming from the block itself so it's not a cpu spike or output clipping.
    Maybe the random LFO shifts the chorus delay time to impossible or irrational values?
     
  12. DLC86

    DLC86
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    1) I'm talking about block's internal Lfo, I'm not attaching anything

    2)
     
  13. lwknives

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    Just double checking, a lot of people will write things like "everything" and actually mean "all the ones I tried".
    I haven't had a chance to try the random or square wave LFOs in the chorus yet.
    Has anybody's else tried this?
     
  14. #14 DLC86, Apr 21, 2017 at 8:43 AM
    Last edited: Apr 21, 2017 at 9:58 AM
    DLC86

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    If I write everything it means everything ;)

    Anyway, I just found another strange behaviour in the chorus block, whenever I change the number of voices lfo type switches back to sine, and if I change lfo type again to something else the number of voices goes back to 2, basically it's possible to have more than 2 voices only with a sine lfo.
    Is it supposed to work like this or is it another bug?
     

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